diff options
Diffstat (limited to 'modules')
42 files changed, 3817 insertions, 0 deletions
diff --git a/modules/ray/ray.c b/modules/ray/ray.c new file mode 100644 index 0000000..60d08cf --- /dev/null +++ b/modules/ray/ray.c @@ -0,0 +1,161 @@ +#include <stdint.h> +#include <inttypes.h> +#include <math.h> + +#include "fb.h" +#include "rototiller.h" +#include "util.h" + +#include "ray_camera.h" +#include "ray_object.h" +#include "ray_scene.h" +#include "ray_threads.h" + +/* Copyright (C) 2016 Vito Caputo <vcaputo@pengaru.com> */ + +/* ray trace a simple scene into the fragment */ +static void ray(fb_fragment_t *fragment) +{ + static ray_object_t objects[] = { + { + .plane = { + .type = RAY_OBJECT_TYPE_PLANE, + .surface = { + .color = { .x = 0.4, .y = 0.2, .z = 0.5 }, + .diffuse = 1.0f, + .specular = 0.2f, + }, + .normal = { .x = 0.0, .y = 1.0, .z = 0.0 }, + .distance = -3.2f, + } + }, { + .sphere = { + .type = RAY_OBJECT_TYPE_SPHERE, + .surface = { + .color = { .x = 1.0, .y = 0.0, .z = 0.0 }, + .diffuse = 1.0f, + .specular = 0.05f, + }, + .center = { .x = 0.5, .y = 1.0, .z = 0.0 }, + .radius = 1.2f, + } + }, { + .sphere = { + .type = RAY_OBJECT_TYPE_SPHERE, + .surface = { + .color = { .x = 0.0, .y = 0.0, .z = 1.0 }, + .diffuse = 1.0f, + .specular = 1.0f, + }, + .center = { .x = -2.0, .y = 1.0, .z = 0.0 }, + .radius = 0.9f, + } + }, { + .sphere = { + .type = RAY_OBJECT_TYPE_SPHERE, + .surface = { + .color = { .x = 0.0, .y = 1.0, .z = 1.0 }, + .diffuse = 1.0f, + .specular = 1.0f, + }, + .center = { .x = 2.0, .y = -1.0, .z = 0.0 }, + .radius = 1.0f, + } + }, { + .sphere = { + .type = RAY_OBJECT_TYPE_SPHERE, + .surface = { + .color = { .x = 0.0, .y = 1.0, .z = 0.0 }, + .diffuse = 1.0f, + .specular = 1.0f, + }, + .center = { .x = 0.2, .y = -1.25, .z = 0.0 }, + .radius = 0.6f, + } + }, { + .light = { + .type = RAY_OBJECT_TYPE_LIGHT, + .brightness = 1.0, + .emitter = { + .point.type = RAY_LIGHT_EMITTER_TYPE_POINT, + .point.center = { .x = 3.0f, .y = 3.0f, .z = 3.0f }, + .point.surface = { + .color = { .x = 1.0f, .y = 1.0f, .z = 1.0f }, + }, + } + } + } + }; + + ray_camera_t camera = { + .position = { .x = 0.0, .y = 0.0, .z = 6.0 }, + .orientation = { + .yaw = RAY_EULER_DEGREES(0.0f), + .pitch = RAY_EULER_DEGREES(0.0f), + .roll = RAY_EULER_DEGREES(180.0f), + }, + .focal_length = 700.0f, + .width = fragment->width, + .height = fragment->height, + }; + + static ray_scene_t scene = { + .objects = objects, + .n_objects = nelems(objects), + .lights = &objects[5], + .n_lights = 1, + .ambient_color = { .x = 1.0f, .y = 1.0f, .z = 1.0f }, + .ambient_brightness = .04f, + }; + static int initialized; + static ray_threads_t *threads; + static fb_fragment_t *fragments; + static unsigned ncpus; +#if 1 + /* animated point light source */ + static double r; + + r += .02; + + scene.lights[0].light.emitter.point.center.x = cosf(r) * 3.5f; + scene.lights[0].light.emitter.point.center.z = sinf(r) * 3.5f; + camera.orientation.yaw = sinf(r) / 4; + camera.orientation.pitch = sinf(r * 10) / 100; + camera.orientation.roll = RAY_EULER_DEGREES(180.0f) + cosf(r) / 10; + camera.position.x = cosf(r) / 10; + camera.position.z = 4.0f + sinf(r) / 10; +#endif + + if (!initialized) { + initialized = 1; + ncpus = get_ncpus(); + + if (ncpus > 1) { + threads = ray_threads_create(ncpus - 1); + fragments = malloc(sizeof(fb_fragment_t) * ncpus); + } + } + + if (ncpus > 1) { + /* Always recompute the fragments[] geometry. + * This way the fragment geometry can change at any moment and things will + * continue functioning, which may prove important later on. + * (imagine things like a preview window, or perhaps composite modules + * which call on other modules supplying virtual fragments of varying dimensions..) + */ + fb_fragment_divide(fragment, ncpus, fragments); + } else { + fragments = fragment; + } + + ray_scene_render_fragments(&scene, &camera, threads, fragments); +} + + +rototiller_renderer_t ray_renderer = { + .render = ray, + .name = "ray", + .description = "Multi-threaded ray tracer", + .author = "Vito Caputo <vcaputo@pengaru.com>", + .license = "GPLv2", +}; diff --git a/modules/ray/ray.h b/modules/ray/ray.h new file mode 100644 index 0000000..d33f96a --- /dev/null +++ b/modules/ray/ray.h @@ -0,0 +1,8 @@ +#ifndef _RAY_RAY_H +#define _RAY_RAY_H + +#include "fb.h" + +void ray(fb_fragment_t *fragment); + +#endif diff --git a/modules/ray/ray_3f.h b/modules/ray/ray_3f.h new file mode 100644 index 0000000..8408abb --- /dev/null +++ b/modules/ray/ray_3f.h @@ -0,0 +1,161 @@ +#ifndef _RAY_3F_H +#define _RAY_3F_H + +#include <math.h> + +typedef struct ray_3f_t { + float x, y, z; +} ray_3f_t; + + +/* return the result of (a + b) */ +static inline ray_3f_t ray_3f_add(ray_3f_t *a, ray_3f_t *b) +{ + ray_3f_t res = { + .x = a->x + b->x, + .y = a->y + b->y, + .z = a->z + b->z, + }; + + return res; +} + + +/* return the result of (a - b) */ +static inline ray_3f_t ray_3f_sub(ray_3f_t *a, ray_3f_t *b) +{ + ray_3f_t res = { + .x = a->x - b->x, + .y = a->y - b->y, + .z = a->z - b->z, + }; + + return res; +} + + +/* return the result of (-v) */ +static inline ray_3f_t ray_3f_negate(ray_3f_t *v) +{ + ray_3f_t res = { + .x = -v->x, + .y = -v->y, + .z = -v->z, + }; + + return res; +} + + +/* return the result of (a * b) */ +static inline ray_3f_t ray_3f_mult(ray_3f_t *a, ray_3f_t *b) +{ + ray_3f_t res = { + .x = a->x * b->x, + .y = a->y * b->y, + .z = a->z * b->z, + }; + + return res; +} + + +/* return the result of (v * scalar) */ +static inline ray_3f_t ray_3f_mult_scalar(ray_3f_t *v, float scalar) +{ + ray_3f_t res = { + .x = v->x * scalar, + .y = v->y * scalar, + .z = v->z * scalar, + }; + + return res; +} + + +/* return the result of (uv / scalar) */ +static inline ray_3f_t ray_3f_div_scalar(ray_3f_t *v, float scalar) +{ + ray_3f_t res = { + .x = v->x / scalar, + .y = v->y / scalar, + .z = v->z / scalar, + }; + + return res; +} + + +/* return the result of (a . b) */ +static inline float ray_3f_dot(ray_3f_t *a, ray_3f_t *b) +{ + return a->x * b->x + a->y * b->y + a->z * b->z; +} + + +/* return the length of the supplied vector */ +static inline float ray_3f_length(ray_3f_t *v) +{ + return sqrtf(ray_3f_dot(v, v)); +} + + +/* return the normalized form of the supplied vector */ +static inline ray_3f_t ray_3f_normalize(ray_3f_t *v) +{ + ray_3f_t nv; + float f; + + f = 1.0f / ray_3f_length(v); + + nv.x = f * v->x; + nv.y = f * v->y; + nv.z = f * v->z; + + return nv; +} + + +/* return the distance between two arbitrary points */ +static inline float ray_3f_distance(ray_3f_t *a, ray_3f_t *b) +{ + return sqrtf(powf(a->x - b->x, 2) + powf(a->y - b->y, 2) + powf(a->z - b->z, 2)); +} + + +/* return the cross product of two unit vectors */ +static inline ray_3f_t ray_3f_cross(ray_3f_t *a, ray_3f_t *b) +{ + ray_3f_t product; + + product.x = a->y * b->z - a->z * b->y; + product.y = a->z * b->x - a->x * b->z; + product.z = a->x * b->y - a->y * b->x; + + return product; +} + + +/* return the linearly interpolated vector between the two vectors at point alpha (0-1.0) */ +static inline ray_3f_t ray_3f_lerp(ray_3f_t *a, ray_3f_t *b, float alpha) +{ + ray_3f_t lerp_a, lerp_b; + + lerp_a = ray_3f_mult_scalar(a, 1.0f - alpha); + lerp_b = ray_3f_mult_scalar(b, alpha); + + return ray_3f_add(&lerp_a, &lerp_b); +} + + +/* return the normalized linearly interpolated vector between the two vectors at point alpha (0-1.0) */ +static inline ray_3f_t ray_3f_nlerp(ray_3f_t *a, ray_3f_t *b, float alpha) +{ + ray_3f_t lerp; + + lerp = ray_3f_lerp(a, b, alpha); + + return ray_3f_normalize(&lerp); +} + +#endif diff --git a/modules/ray/ray_camera.c b/modules/ray/ray_camera.c new file mode 100644 index 0000000..0703c2e --- /dev/null +++ b/modules/ray/ray_camera.c @@ -0,0 +1,85 @@ +#include "fb.h" + +#include "ray_camera.h" +#include "ray_euler.h" + + +/* Produce a vector from the provided orientation vectors and proportions. */ +static ray_3f_t project_corner(ray_3f_t *forward, ray_3f_t *left, ray_3f_t *up, float focal_length, float horiz, float vert) +{ + ray_3f_t tmp; + ray_3f_t corner; + + corner = ray_3f_mult_scalar(forward, focal_length); + tmp = ray_3f_mult_scalar(left, horiz); + corner = ray_3f_add(&corner, &tmp); + tmp = ray_3f_mult_scalar(up, vert); + corner = ray_3f_add(&corner, &tmp); + + return ray_3f_normalize(&corner); +} + + +/* Produce vectors for the corners of the entire camera frame, used for interpolation. */ +static void project_corners(ray_camera_t *camera, ray_camera_frame_t *frame) +{ + ray_3f_t forward, left, up, right, down; + float half_horiz = (float)camera->width / 2.0f; + float half_vert = (float)camera->height / 2.0f; + + ray_euler_basis(&camera->orientation, &forward, &up, &left); + right = ray_3f_negate(&left); + down = ray_3f_negate(&up); + + frame->nw = project_corner(&forward, &left, &up, camera->focal_length, half_horiz, half_vert); + frame->ne = project_corner(&forward, &right, &up, camera->focal_length, half_horiz, half_vert); + frame->se = project_corner(&forward, &right, &down, camera->focal_length, half_horiz, half_vert); + frame->sw = project_corner(&forward, &left, &down, camera->focal_length, half_horiz, half_vert); +} + + +/* Begin a frame for the fragment of camera projection, initializing frame and ray. */ +void ray_camera_frame_begin(ray_camera_t *camera, fb_fragment_t *fragment, ray_ray_t *ray, ray_camera_frame_t *frame) +{ + /* References are kept to the camera, fragment, and ray to be traced. + * The ray is maintained as we step through the frame, that is the + * purpose of this api. + * + * Since the ray direction should be a normalized vector, the obvious + * implementation is a bit costly. The camera frame api hides this + * detail so we can explore interpolation techniques to potentially + * lessen the per-pixel cost. + */ + frame->camera = camera; + frame->fragment = fragment; + frame->ray = ray; + + frame->x = frame->y = 0; + + /* From camera->orientation and camera->focal_length compute the vectors + * through the viewport's corners, and place these normalized vectors + * in frame->(nw,ne,sw,se). + * + * These can than be interpolated between to produce the ray vectors + * throughout the frame's fragment. The efficient option of linear + * interpolation will not maintain the unit vector length, so to + * produce normalized interpolated directions will require the costly + * normalize function. + * + * I'm hoping a simple length correction table can be used to fixup the + * linearly interpolated vectors to make them unit vectors with just + * scalar multiplication instead of the sqrt of normalize. + */ + project_corners(camera, frame); + + frame->x_delta = 1.0f / (float)camera->width; + frame->y_delta = 1.0f / (float)camera->height; + frame->x_alpha = frame->x_delta * (float)fragment->x; + frame->y_alpha = frame->y_delta * (float)fragment->y; + + frame->cur_w = ray_3f_nlerp(&frame->nw, &frame->sw, frame->y_alpha); + frame->cur_e = ray_3f_nlerp(&frame->ne, &frame->se, frame->y_alpha); + + ray->origin = camera->position; + ray->direction = frame->cur_w; +} diff --git a/modules/ray/ray_camera.h b/modules/ray/ray_camera.h new file mode 100644 index 0000000..387f8c5 --- /dev/null +++ b/modules/ray/ray_camera.h @@ -0,0 +1,77 @@ +#ifndef _RAY_CAMERA_H +#define _RAY_CAMERA_H + +#include <math.h> + +#include "fb.h" + +#include "ray_3f.h" +#include "ray_euler.h" +#include "ray_ray.h" + + +typedef struct ray_camera_t { + ray_3f_t position; /* position of camera, the origin of all its rays */ + ray_euler_t orientation; /* orientation of the camera */ + float focal_length; /* controls the field of view */ + unsigned width; /* width of camera viewport in pixels */ + unsigned height; /* height of camera viewport in pixels */ +} ray_camera_t; + + +typedef struct ray_camera_frame_t { + ray_camera_t *camera; /* the camera supplied to frame_begin() */ + fb_fragment_t *fragment; /* the fragment supplied to frame_begin() */ + ray_ray_t *ray; /* the ray supplied to frame_begin(), which gets updated as we step through the frame. */ + + ray_3f_t nw, ne, sw, se; /* directions pointing through the corners of the frame fragment */ + ray_3f_t cur_w, cur_e; /* current row's west and east ends */ + float x_alpha, y_alpha; /* interpolation position along the x and y axis */ + float x_delta, y_delta; /* interpolation step delta along the x and y axis */ + unsigned x, y; /* integral position within frame fragment */ +} ray_camera_frame_t; + + +void ray_camera_frame_begin(ray_camera_t *camera, fb_fragment_t *fragment, ray_ray_t *ray, ray_camera_frame_t *frame); + + +/* Step the ray through the frame on the x axis, returns 1 when rays remain on this axis, 0 at the end. */ +/* When 1 is returned, frame->ray is left pointing through the new coordinate. */ +static inline int ray_camera_frame_x_step(ray_camera_frame_t *frame) +{ + frame->x++; + + if (frame->x >= frame->fragment->width) { + frame->x = 0; + frame->x_alpha = frame->x_delta * (float)frame->fragment->x; + return 0; + } + + frame->x_alpha += frame->x_delta; + frame->ray->direction = ray_3f_nlerp(&frame->cur_w, &frame->cur_e, frame->x_alpha); + + return 1; +} + + +/* Step the ray through the frame on the y axis, returns 1 when rays remain on this axis, 0 at the end. */ +/* When 1 is returned, frame->ray is left pointing through the new coordinate. */ +static inline int ray_camera_frame_y_step(ray_camera_frame_t *frame) +{ + frame->y++; + + if (frame->y >= frame->fragment->height) { + frame->y = 0; + frame->y_alpha = frame->y_delta * (float)frame->fragment->y; + return 0; + } + + frame->y_alpha += frame->y_delta; + frame->cur_w = ray_3f_nlerp(&frame->nw, &frame->sw, frame->y_alpha); + frame->cur_e = ray_3f_nlerp(&frame->ne, &frame->se, frame->y_alpha); + frame->ray->direction = frame->cur_w; + + return 1; +} + +#endif diff --git a/modules/ray/ray_color.h b/modules/ray/ray_color.h new file mode 100644 index 0000000..9fe62c1 --- /dev/null +++ b/modules/ray/ray_color.h @@ -0,0 +1,29 @@ +#ifndef _RAY_COLOR_H +#define _RAY_COLOR_H + +#include <stdint.h> + +#include "ray_3f.h" + +typedef ray_3f_t ray_color_t; + +/* convert a vector into a packed, 32-bit rgb pixel value */ +static inline uint32_t ray_color_to_uint32_rgb(ray_color_t color) { + uint32_t pixel; + + /* doing this all per-pixel, ugh. */ + + if (color.x > 1.0f) color.x = 1.0f; + if (color.y > 1.0f) color.y = 1.0f; + if (color.z > 1.0f) color.z = 1.0f; + + pixel = (uint32_t)(color.x * 255.0f); + pixel <<= 8; + pixel |= (uint32_t)(color.y * 255.0f); + pixel <<= 8; + pixel |= (uint32_t)(color.z * 255.0f); + + return pixel; +} + +#endif diff --git a/modules/ray/ray_euler.h b/modules/ray/ray_euler.h new file mode 100644 index 0000000..86f5221 --- /dev/null +++ b/modules/ray/ray_euler.h @@ -0,0 +1,45 @@ +#ifndef _RAY_EULER_H +#define _RAY_EULER_H + +#include <math.h> + +#include "ray_3f.h" + + +/* euler angles are convenient for describing orientation */ +typedef struct ray_euler_t { + float pitch; /* pitch in radiasn */ + float yaw; /* yaw in radians */ + float roll; /* roll in radians */ +} ray_euler_t; + + +/* convenience macro for converting degrees to radians */ +#define RAY_EULER_DEGREES(_deg) \ + (_deg * (2 * M_PI / 360.0f)) + + +/* produce basis vectors from euler angles */ +static inline void ray_euler_basis(ray_euler_t *e, ray_3f_t *forward, ray_3f_t *up, ray_3f_t *left) +{ + float cos_yaw = cosf(e->yaw); + float sin_yaw = sinf(e->yaw); + float cos_roll = cosf(e->roll); + float sin_roll = sinf(e->roll); + float cos_pitch = cosf(e->pitch); + float sin_pitch = sinf(e->pitch); + + forward->x = sin_yaw; + forward->y = -sin_pitch * cos_yaw; + forward->z = cos_pitch * cos_yaw; + + up->x = -cos_yaw * sin_roll; + up->y = -sin_pitch * sin_yaw * sin_roll + cos_pitch * cos_roll; + up->z = cos_pitch * sin_yaw * sin_roll + sin_pitch * cos_roll; + + left->x = cos_yaw * cos_roll; + left->y = sin_pitch * sin_yaw * cos_roll + cos_pitch * sin_roll; + left->z = -cos_pitch * sin_yaw * cos_roll + sin_pitch * sin_roll; +} + +#endif diff --git a/modules/ray/ray_light_emitter.h b/modules/ray/ray_light_emitter.h new file mode 100644 index 0000000..3b5509e --- /dev/null +++ b/modules/ray/ray_light_emitter.h @@ -0,0 +1,18 @@ +#ifndef _RAY_LIGHT_EMITTER_H +#define _RAY_LIGHT_EMITTER_H + +#include "ray_object_point.h" +#include "ray_object_sphere.h" + +typedef enum ray_light_emitter_type_t { + RAY_LIGHT_EMITTER_TYPE_SPHERE, + RAY_LIGHT_EMITTER_TYPE_POINT, +} ray_light_emitter_type_t; + +typedef union ray_light_emitter_t { + ray_light_emitter_type_t type; + ray_object_sphere_t sphere; + ray_object_point_t point; +} ray_light_emitter_t; + +#endif diff --git a/modules/ray/ray_object.c b/modules/ray/ray_object.c new file mode 100644 index 0000000..8b324e5 --- /dev/null +++ b/modules/ray/ray_object.c @@ -0,0 +1,67 @@ +#include "ray_object.h" +#include "ray_object_light.h" +#include "ray_object_plane.h" +#include "ray_object_point.h" +#include "ray_object_sphere.h" +#include "ray_ray.h" +#include "ray_scene.h" +#include "ray_surface.h" + + +/* Determine if a ray intersects object. + * If the object is intersected, store where along the ray the intersection occurs in res_distance. + */ +int ray_object_intersects_ray(ray_object_t *object, ray_ray_t *ray, float *res_distance) +{ + switch (object->type) { + case RAY_OBJECT_TYPE_SPHERE: + return ray_object_sphere_intersects_ray(&object->sphere, ray, res_distance); + + case RAY_OBJECT_TYPE_POINT: + return ray_object_point_intersects_ray(&object->point, ray, res_distance); + + case RAY_OBJECT_TYPE_PLANE: + return ray_object_plane_intersects_ray(&object->plane, ray, res_distance); + + case RAY_OBJECT_TYPE_LIGHT: + return ray_object_light_intersects_ray(&object->light, ray, res_distance); + } +} + + +/* Return the surface normal of object @ point */ +ray_3f_t ray_object_normal(ray_object_t *object, ray_3f_t *point) +{ + switch (object->type) { + case RAY_OBJECT_TYPE_SPHERE: + return ray_object_sphere_normal(&object->sphere, point); + + case RAY_OBJECT_TYPE_POINT: + return ray_object_point_normal(&object->point, point); + + case RAY_OBJECT_TYPE_PLANE: + return ray_object_plane_normal(&object->plane, point); + + case RAY_OBJECT_TYPE_LIGHT: + return ray_object_light_normal(&object->light, point); + } +} + + +/* Return the surface of object @ point */ +ray_surface_t ray_object_surface(ray_object_t *object, ray_3f_t *point) +{ + switch (object->type) { + case RAY_OBJECT_TYPE_SPHERE: + return ray_object_sphere_surface(&object->sphere, point); + + case RAY_OBJECT_TYPE_POINT: + return ray_object_point_surface(&object->point, point); + + case RAY_OBJECT_TYPE_PLANE: + return ray_object_plane_surface(&object->plane, point); + + case RAY_OBJECT_TYPE_LIGHT: + return ray_object_light_surface(&object->light, point); + } +} diff --git a/modules/ray/ray_object.h b/modules/ray/ray_object.h new file mode 100644 index 0000000..3dc27d1 --- /dev/null +++ b/modules/ray/ray_object.h @@ -0,0 +1,25 @@ +#ifndef _RAY_OBJECT_H +#define _RAY_OBJECT_H + +#include "ray_object_light.h" +#include "ray_object_plane.h" +#include "ray_object_point.h" +#include "ray_object_sphere.h" +#include "ray_object_type.h" +#include "ray_ray.h" +#include "ray_scene.h" +#include "ray_surface.h" + +typedef union ray_object_t { + ray_object_type_t type; + ray_object_sphere_t sphere; + ray_object_point_t point; + ray_object_plane_t plane; + ray_object_light_t light; +} ray_object_t; + +int ray_object_intersects_ray(ray_object_t *object, ray_ray_t *ray, float *res_distance); +ray_3f_t ray_object_normal(ray_object_t *object, ray_3f_t *point); +ray_surface_t ray_object_surface(ray_object_t *object, ray_3f_t *point); + +#endif diff --git a/modules/ray/ray_object_light.h b/modules/ray/ray_object_light.h new file mode 100644 index 0000000..73cf917 --- /dev/null +++ b/modules/ray/ray_object_light.h @@ -0,0 +1,60 @@ +#ifndef _RAY_OBJECT_LIGHT_H +#define _RAY_OBJECT_LIGHT_H + +#include "ray_light_emitter.h" +#include "ray_object_light.h" +#include "ray_object_point.h" +#include "ray_object_sphere.h" +#include "ray_object_type.h" +#include "ray_ray.h" +#include "ray_scene.h" +#include "ray_surface.h" + + +typedef struct ray_object_light_t { + ray_object_type_t type; + float brightness; + ray_light_emitter_t emitter; +} ray_object_light_t; + + +/* TODO: point is really the only one I've implemented... */ +static inline int ray_object_light_intersects_ray(ray_object_light_t *light, ray_ray_t *ray, float *res_distance) +{ + switch (light->emitter.type) { + case RAY_LIGHT_EMITTER_TYPE_POINT: + return ray_object_point_intersects_ray(&light->emitter.point, ray, res_distance); + + case RAY_LIGHT_EMITTER_TYPE_SPHERE: + return ray_object_sphere_intersects_ray(&light->emitter.sphere, ray, res_distance); + } +} + + +static inline ray_3f_t ray_object_light_normal(ray_object_light_t *light, ray_3f_t *point) +{ + ray_3f_t normal; + + /* TODO */ + switch (light->emitter.type) { + case RAY_LIGHT_EMITTER_TYPE_SPHERE: + return normal; + + case RAY_LIGHT_EMITTER_TYPE_POINT: + return normal; + } +} + + +static inline ray_surface_t ray_object_light_surface(ray_object_light_t *light, ray_3f_t *point) +{ + switch (light->emitter.type) { + case RAY_LIGHT_EMITTER_TYPE_SPHERE: + return ray_object_sphere_surface(&light->emitter.sphere, point); + + case RAY_LIGHT_EMITTER_TYPE_POINT: + return ray_object_point_surface(&light->emitter.point, point); + } +} + +#endif diff --git a/modules/ray/ray_object_plane.h b/modules/ray/ray_object_plane.h new file mode 100644 index 0000000..96f204e --- /dev/null +++ b/modules/ray/ray_object_plane.h @@ -0,0 +1,47 @@ +#ifndef _RAY_OBJECT_PLANE_H +#define _RAY_OBJECT_PLANE_H + +#include "ray_object_type.h" +#include "ray_ray.h" +#include "ray_scene.h" +#include "ray_surface.h" + + +typedef struct ray_object_plane_t { + ray_object_type_t type; + ray_surface_t surface; + ray_3f_t normal; + float distance; +} ray_object_plane_t; + + +static inline int ray_object_plane_intersects_ray(ray_object_plane_t *plane, ray_ray_t *ray, float *res_distance) +{ + float d = ray_3f_dot(&plane->normal, &ray->direction); + + if (d != 0) { + float distance = -(ray_3f_dot(&plane->normal, &ray->origin) + plane->distance) / d; + + if (distance > 0) { + *res_distance = distance; + + return 1; + } + } + + return 0; +} + + +static inline ray_3f_t ray_object_plane_normal(ray_object_plane_t *plane, ray_3f_t *point) +{ + return plane->normal; +} + + +static inline ray_surface_t ray_object_plane_surface(ray_object_plane_t *plane, ray_3f_t *point) +{ + return plane->surface; +} + +#endif diff --git a/modules/ray/ray_object_point.h b/modules/ray/ray_object_point.h new file mode 100644 index 0000000..5c83a68 --- /dev/null +++ b/modules/ray/ray_object_point.h @@ -0,0 +1,38 @@ +#ifndef _RAY_OBJECT_POINT_H +#define _RAY_OBJECT_POINT_H + +#include "ray_3f.h" +#include "ray_object_type.h" +#include "ray_ray.h" +#include "ray_scene.h" +#include "ray_surface.h" + + +typedef struct ray_object_point_t { + ray_object_type_t type; + ray_surface_t surface; + ray_3f_t center; +} ray_object_point_t; + + +static inline int ray_object_point_intersects_ray(ray_object_point_t *point, ray_ray_t *ray, float *res_distance) +{ + /* TODO: determine a ray:point intersection */ + return 0; +} + + +static inline ray_3f_t ray_object_point_normal(ray_object_point_t *point, ray_3f_t *_point) +{ + ray_3f_t normal; + + return normal; +} + + +static inline ray_surface_t ray_object_point_surface(ray_object_point_t *point, ray_3f_t *_point) +{ + return point->surface; +} + +#endif diff --git a/modules/ray/ray_object_sphere.h b/modules/ray/ray_object_sphere.h new file mode 100644 index 0000000..6786bb7 --- /dev/null +++ b/modules/ray/ray_object_sphere.h @@ -0,0 +1,66 @@ +#ifndef _RAY_OBJECT_SPHERE_H +#define _RAY_OBJECT_SPHERE_H + +#include <math.h> +#include <stdio.h> + +#include "ray_3f.h" +#include "ray_color.h" +#include "ray_object_type.h" +#include "ray_ray.h" +#include "ray_scene.h" +#include "ray_surface.h" + + +typedef struct ray_object_sphere_t { + ray_object_type_t type; + ray_surface_t surface; + ray_3f_t center; + float radius; +} ray_object_sphere_t; + + +static inline int ray_object_sphere_intersects_ray(ray_object_sphere_t *sphere, ray_ray_t *ray, float *res_distance) +{ + ray_3f_t v = ray_3f_sub(&ray->origin, &sphere->center); + float b = ray_3f_dot(&v, &ray->direction); + float disc = (sphere->radius * sphere->radius) - ray_3f_dot(&v, &v) + (b * b); + + if (disc > 0) { + float i1, i2; + + disc = sqrtf(disc); + + i1 = b - disc; + i2 = b + disc; + + if (i2 > 0 && i1 > 0) { + *res_distance = i1; + return 1; + } + } + + return 0; +} + + +/* return the normal of the surface at the specified point */ +static inline ray_3f_t ray_object_sphere_normal(ray_object_sphere_t *sphere, ray_3f_t *point) +{ + ray_3f_t normal; + + normal = ray_3f_sub(point, &sphere->center); + normal = ray_3f_div_scalar(&normal, sphere->radius); /* normalize without the sqrt() */ + + return normal; +} + + +/* return the surface of the sphere @ point */ +static inline ray_surface_t ray_object_sphere_surface(ray_object_sphere_t *sphere, ray_3f_t *point) +{ + /* uniform solids for now... */ + return sphere->surface; +} + +#endif diff --git a/modules/ray/ray_object_type.h b/modules/ray/ray_object_type.h new file mode 100644 index 0000000..6ce20f5 --- /dev/null +++ b/modules/ray/ray_object_type.h @@ -0,0 +1,11 @@ +#ifndef _RAY_OBJECT_TYPE_H +#define _RAY_OBJECT_TYPE_H + +typedef enum ray_object_type_t { + RAY_OBJECT_TYPE_SPHERE, + RAY_OBJECT_TYPE_POINT, + RAY_OBJECT_TYPE_PLANE, + RAY_OBJECT_TYPE_LIGHT, +} ray_object_type_t; + +#endif diff --git a/modules/ray/ray_ray.h b/modules/ray/ray_ray.h new file mode 100644 index 0000000..91469a2 --- /dev/null +++ b/modules/ray/ray_ray.h @@ -0,0 +1,11 @@ +#ifndef _RAY_RAY_H +#define _RAY_RAY_H + +#include "ray_3f.h" + +typedef struct ray_ray_t { + ray_3f_t origin; + ray_3f_t direction; +} ray_ray_t; + +#endif diff --git a/modules/ray/ray_scene.c b/modules/ray/ray_scene.c new file mode 100644 index 0000000..e44990b --- /dev/null +++ b/modules/ray/ray_scene.c @@ -0,0 +1,188 @@ +#include <stdlib.h> +#include <math.h> + +#include "fb.h" + +#include "ray_camera.h" +#include "ray_color.h" +#include "ray_object.h" +#include "ray_ray.h" +#include "ray_scene.h" +#include "ray_threads.h" + +#define MAX_RECURSION_DEPTH 5 + + +static ray_color_t trace_ray(ray_scene_t *scene, ray_ray_t *ray, unsigned depth); + + +/* Determine if the ray is obstructed by an object within the supplied distance, for shadows */ +static inline int ray_is_obstructed(ray_scene_t *scene, ray_ray_t *ray, float distance) +{ + unsigned i; + + for (i = 0; i < scene->n_objects; i++) { + float ood; + + if (scene->objects[i].type == RAY_OBJECT_TYPE_LIGHT) + continue; + + if (ray_object_intersects_ray(&scene->objects[i], ray, &ood) && + ood < distance) { + return 1; + } + } + + return 0; +} + + +/* Determine the color @ distance on ray on object viewed from origin */ +static inline ray_color_t shade_ray(ray_scene_t *scene, ray_ray_t *ray, ray_object_t *object, float distance, unsigned depth) +{ + ray_surface_t surface; + ray_color_t color; + ray_3f_t rvec = ray_3f_mult_scalar(&ray->direction, distance); + ray_3f_t intersection = ray_3f_sub(&ray->origin, &rvec); + ray_3f_t normal = ray_object_normal(object, &intersection); + unsigned i; + + surface = ray_object_surface(object, &intersection); + color = ray_3f_mult_scalar(&scene->ambient_color, scene->ambient_brightness); + color = ray_3f_mult(&surface.color, &color); + + /* visit lights for shadows and illumination */ + for (i = 0; i < scene->n_lights; i++) { + ray_3f_t lvec = ray_3f_sub(&scene->lights[i].light.emitter.point.center, &intersection); + float ldist = ray_3f_length(&lvec); + float lvec_normal_dot; + ray_ray_t shadow_ray; + + lvec = ray_3f_mult_scalar(&lvec, (1.0f / ldist)); /* normalize lvec */ +#if 1 + /* skip this light if it's obstructed, + * we must shift the origin slightly towards the light to prevent + * spurious self-obstruction at the ray:object intersection */ + /* negate the light vector so it's pointed at the light rather than from it */ + shadow_ray.direction = ray_3f_negate(&lvec); + shadow_ray.origin = ray_3f_mult_scalar(&shadow_ray.direction, 0.00001f); + shadow_ray.origin = ray_3f_add(&shadow_ray.origin, &intersection); + + if (ray_is_obstructed(scene, &shadow_ray, ldist)) + continue; +#endif + lvec_normal_dot = ray_3f_dot(&normal, &lvec); + + if (lvec_normal_dot > 0) { +#if 1 + float rvec_lvec_dot = ray_3f_dot(&ray->direction, &lvec); + ray_color_t diffuse; + ray_color_t specular; + + diffuse = ray_3f_mult_scalar(&surface.color, lvec_normal_dot); + diffuse = ray_3f_mult_scalar(&diffuse, surface.diffuse); + color = ray_3f_add(&color, &diffuse); + + /* FIXME: assumes light is a point for its color, and 20 is a constant "Phong exponent", + * which should really be object/surface-specific + */ + specular = ray_3f_mult_scalar(&scene->lights[i].light.emitter.point.surface.color, powf(rvec_lvec_dot, 20)); + specular = ray_3f_mult_scalar(&specular, surface.specular); + color = ray_3f_add(&color, &specular); +#else + ray_color_t diffuse; + + diffuse = ray_3f_mult_scalar(&surface.color, lvec_normal_dot); + color = ray_3f_add(&color, &diffuse); +#endif + } + } + + /* generate a reflection ray */ +#if 1 + float dot = ray_3f_dot(&ray->direction, &normal); + ray_ray_t reflected_ray = { .direction = ray_3f_mult_scalar(&normal, dot * 2.0f) }; + ray_3f_t reflection; + + reflected_ray.origin = intersection; + reflected_ray.direction = ray_3f_sub(&ray->direction, &reflected_ray.direction); + + reflection = trace_ray(scene, &reflected_ray, depth + 1); + reflection = ray_3f_mult_scalar(&reflection, surface.specular); + color = ray_3f_add(&color, &reflection); +#endif + + /* TODO: generate a refraction ray */ + + return color; +} + + +static ray_color_t trace_ray(ray_scene_t *scene, ray_ray_t *ray, unsigned depth) +{ + ray_object_t *nearest_object = NULL; + float nearest_object_distance = INFINITY; + ray_color_t color = { .x = 0.0, .y = 0.0, .z = 0.0 }; + unsigned i; + + depth++; + if (depth > MAX_RECURSION_DEPTH) + return color; + + for (i = 0; i < scene->n_objects; i++) { + float distance; + + /* Does this ray intersect object? */ + if (ray_object_intersects_ray(&scene->objects[i], ray, &distance)) { + + /* Is it the nearest intersection? */ + if (!nearest_object || + distance < nearest_object_distance) { + nearest_object = &scene->objects[i]; + nearest_object_distance = distance; + } + } + } + + if (nearest_object) + color = shade_ray(scene, ray, nearest_object, nearest_object_distance, depth); + + depth--; + + return color; +} + + +void ray_scene_render_fragment(ray_scene_t *scene, ray_camera_t *camera, fb_fragment_t *fragment) +{ + ray_camera_frame_t frame; + ray_ray_t ray; + uint32_t *buf = fragment->buf; + unsigned stride = fragment->stride / 4; + + ray_camera_frame_begin(camera, fragment, &ray, &frame); + do { + do { + *buf = ray_color_to_uint32_rgb(trace_ray(scene, &ray, 0)); + buf++; + } while (ray_camera_frame_x_step(&frame)); + + buf += stride; + } while (ray_camera_frame_y_step(&frame)); +} + +/* we expect fragments[threads->n_threads + 1], or fragments[1] when threads == NULL */ +void ray_scene_render_fragments(ray_scene_t *scene, ray_camera_t *camera, ray_threads_t *threads, fb_fragment_t *fragments) +{ + unsigned n_threads = threads ? threads->n_threads + 1 : 1; + unsigned i; + + for (i = 1; i < n_threads; i++) + ray_thread_fragment_submit(&threads->threads[i - 1], scene, camera, &fragments[i]); + + /* always render the zero fragment in-line */ + ray_scene_render_fragment(scene, camera, &fragments[0]); + + for (i = 1; i < n_threads; i++) + ray_thread_wait_idle(&threads->threads[i - 1]); +} diff --git a/modules/ray/ray_scene.h b/modules/ray/ray_scene.h new file mode 100644 index 0000000..e9781c6 --- /dev/null +++ b/modules/ray/ray_scene.h @@ -0,0 +1,27 @@ +#ifndef _RAY_SCENE_H +#define _RAY_SCENE_H + +#include "fb.h" + +#include "ray_camera.h" +#include "ray_color.h" +#include "ray_ray.h" +#include "ray_threads.h" + +typedef union ray_object_t ray_object_t; + +typedef struct ray_scene_t { + ray_object_t *objects; + unsigned n_objects; + + ray_object_t *lights; + unsigned n_lights; + + ray_color_t ambient_color; + float ambient_brightness; +} ray_scene_t; + +void ray_scene_render_fragments(ray_scene_t *scene, ray_camera_t *camera, ray_threads_t *threads, fb_fragment_t *fragments); +void ray_scene_render_fragment(ray_scene_t *scene, ray_camera_t *camera, fb_fragment_t *fragment); + +#endif diff --git a/modules/ray/ray_surface.h b/modules/ray/ray_surface.h new file mode 100644 index 0000000..b3e3c68 --- /dev/null +++ b/modules/ray/ray_surface.h @@ -0,0 +1,14 @@ +#ifndef _RAY_MATERIAL_H +#define _RAY_MATERIAL_H + +#include "ray_3f.h" +#include "ray_color.h" + +/* Surface properties we expect every object to be able to introspect */ +typedef struct ray_surface_t { + ray_color_t color; + float specular; + float diffuse; +} ray_surface_t; + +#endif diff --git a/modules/ray/ray_threads.c b/modules/ray/ray_threads.c new file mode 100644 index 0000000..2369687 --- /dev/null +++ b/modules/ray/ray_threads.c @@ -0,0 +1,111 @@ +#include <pthread.h> +#include <stdlib.h> + +#include "fb.h" + +#include "ray_scene.h" +#include "ray_threads.h" + +#define BUSY_WAIT_NUM 1000000000 /* How much to spin before sleeping in pthread_cond_wait() */ + +/* for now assuming x86 */ +#define cpu_relax() \ + __asm__ __volatile__ ( "pause\n" : : : "memory") + +/* This is a very simple/naive implementation, there's certainly room for improvement. + * + * Without the BUSY_WAIT_NUM spinning this approach seems to leave a fairly + * substantial proportion of CPU idle while waiting for the render thread to + * complete on my core 2 duo. + * + * It's probably just latency in getting the render thread woken when the work + * is submitted, and since the fragments are split equally the main thread gets + * a head start and has to wait when it finishes first. The spinning is just + * an attempt to avoid going to sleep while the render threads finish, there + * still needs to be improvement in how the work is submitted. + * + * I haven't spent much time on optimizing the raytracer yet. + */ + +static void * ray_thread_func(void *_thread) +{ + ray_thread_t *thread = _thread; + + for (;;) { + pthread_mutex_lock(&thread->mutex); + while (thread->fragment == NULL) + pthread_cond_wait(&thread->cond, &thread->mutex); + + ray_scene_render_fragment(thread->scene, thread->camera, thread->fragment); + thread->fragment = NULL; + pthread_mutex_unlock(&thread->mutex); + pthread_cond_signal(&thread->cond); + } + + return NULL; +} + + +void ray_thread_fragment_submit(ray_thread_t *thread, ray_scene_t *scene, ray_camera_t *camera, fb_fragment_t *fragment) +{ + pthread_mutex_lock(&thread->mutex); + while (thread->fragment != NULL) /* XXX: never true due to ray_thread_wait_idle() */ + pthread_cond_wait(&thread->cond, &thread->mutex); + + thread->fragment = fragment; + thread->scene = scene; + thread->camera = camera; + + pthread_mutex_unlock(&thread->mutex); + pthread_cond_signal(&thread->cond); +} + + +void ray_thread_wait_idle(ray_thread_t *thread) +{ + unsigned n; + + /* Spin before going to sleep, the other thread should not take substantially longer. */ + for (n = 0; thread->fragment != NULL && n < BUSY_WAIT_NUM; n++) + cpu_relax(); + + pthread_mutex_lock(&thread->mutex); + while (thread->fragment != NULL) + pthread_cond_wait(&thread->cond, &thread->mutex); + pthread_mutex_unlock(&thread->mutex); +} + + +ray_threads_t * ray_threads_create(unsigned num) +{ + ray_threads_t *threads; + unsigned i; + + threads = malloc(sizeof(ray_threads_t) + sizeof(ray_thread_t) * num); + if (!threads) + return NULL; + + for (i = 0; i < num; i++) { + pthread_mutex_init(&threads->threads[i].mutex, NULL); + pthread_cond_init(&threads->threads[i].cond, NULL); + threads->threads[i].fragment = NULL; + pthread_create(&threads->threads[i].thread, NULL, ray_thread_func, &threads->threads[i]); + } + threads->n_threads = num; + + return threads; +} + + +void ray_threads_destroy(ray_threads_t *threads) +{ + unsigned i; + + for (i = 0; i < threads->n_threads; i++) + pthread_cancel(threads->threads[i].thread); + + for (i = 0; i < threads->n_threads; i++) + pthread_join(threads->threads[i].thread, NULL); + + free(threads); +} diff --git a/modules/ray/ray_threads.h b/modules/ray/ray_threads.h new file mode 100644 index 0000000..b4c601d --- /dev/null +++ b/modules/ray/ray_threads.h @@ -0,0 +1,30 @@ +#ifndef _RAY_THREADS_H +#define _RAY_THREADS_H + +#include <pthread.h> + +typedef struct ray_scene_t ray_scene_t; +typedef struct ray_camera_t ray_camera_t; +typedef struct fb_fragment_t fb_fragment_t; + +typedef struct ray_thread_t { + pthread_t thread; + pthread_mutex_t mutex; + pthread_cond_t cond; + ray_scene_t *scene; + ray_camera_t *camera; + fb_fragment_t *fragment; +} ray_thread_t; + +typedef struct ray_threads_t { + unsigned n_threads; + ray_thread_t threads[]; +} ray_threads_t; + + +ray_threads_t * ray_threads_create(unsigned num); +void ray_threads_destroy(ray_threads_t *threads); + +void ray_thread_fragment_submit(ray_thread_t *thread, ray_scene_t *scene, ray_camera_t *camera, fb_fragment_t *fragment); +void ray_thread_wait_idle(ray_thread_t *thread); +#endif diff --git a/modules/roto/roto.c b/modules/roto/roto.c new file mode 100644 index 0000000..21e68b7 --- /dev/null +++ b/modules/roto/roto.c @@ -0,0 +1,231 @@ +#include <stdint.h> +#include <inttypes.h> +#include <math.h> + +#include "fb.h" +#include "rototiller.h" + +/* Copyright (C) 2016 Vito Caputo <vcaputo@pengaru.com> */ + +/* Some defines for the fixed-point stuff in render(). */ +#define FIXED_TRIG_LUT_SIZE 4096 /* size of the cos/sin look-up tables */ +#define FIXED_BITS 12 /* fractional bits */ +#define FIXED_EXP 4096 /* 2^FIXED_BITS */ +#define FIXED_COS(_rad) costab[_rad % FIXED_TRIG_LUT_SIZE] +#define FIXED_SIN(_rad) sintab[_rad % FIXED_TRIG_LUT_SIZE] +#define FIXED_MULT(_a, _b) ((_a * _b) >> FIXED_BITS) +#define FIXED_NEW(_i) (_i << FIXED_BITS) +#define FIXED_TO_INT(_f) ((_f) >> FIXED_BITS) + + +/* Draw a rotating checkered 256x256 texture into fragment. (32-bit version) */ +static void roto32(fb_fragment_t *fragment) +{ + static int32_t costab[FIXED_TRIG_LUT_SIZE], sintab[FIXED_TRIG_LUT_SIZE]; + static uint8_t texture[256][256]; + static int initialized; + static uint32_t colors[2]; + static unsigned r, rr; + + int y_cos_r, y_sin_r, x_cos_r, x_sin_r, x_cos_r_init, x_sin_r_init, cos_r, sin_r; + int x, y, stride = fragment->stride / 4, width = fragment->width, height = fragment->height; + uint8_t tx, ty; /* 256x256 texture; 8 bit texture indices to modulo via overflow. */ + uint32_t *buf = fragment->buf; + + if (!initialized) { + int i; + + initialized = 1; + + /* Generate simple checker pattern texture, nothing clever, feel free to play! */ + /* If you modify texture on every frame instead of only @ initialization you can + * produce some neat output. These values are indexed into colors[] below. */ + for (y = 0; y < 128; y++) { + for (x = 0; x < 128; x++) + texture[y][x] = 1; + for (; x < 256; x++) + texture[y][x] = 0; + } + for (; y < 256; y++) { + for (x = 0; x < 128; x++) + texture[y][x] = 0; + for (; x < 256; x++) + texture[y][x] = 1; + } + + /* Generate fixed-point cos & sin LUTs. */ + for (i = 0; i < FIXED_TRIG_LUT_SIZE; i++) { + costab[i] = ((cos((double)2*M_PI*i/FIXED_TRIG_LUT_SIZE))*FIXED_EXP); + sintab[i] = ((sin((double)2*M_PI*i/FIXED_TRIG_LUT_SIZE))*FIXED_EXP); + } + } + + /* This is all done using fixed-point in the hopes of being faster, and yes assumptions + * are being made WRT the overflow of tx/ty as well, only tested on x86_64. */ + cos_r = FIXED_COS(r); + sin_r = FIXED_SIN(r); + + /* Vary the colors, this is just a mashup of sinusoidal rgb values. */ + colors[0] = ((FIXED_TO_INT(FIXED_MULT(FIXED_COS(rr), FIXED_NEW(127))) + 128) << 16) | + ((FIXED_TO_INT(FIXED_MULT(FIXED_SIN(rr / 2), FIXED_NEW(127))) + 128) << 8) | + ((FIXED_TO_INT(FIXED_MULT(FIXED_COS(rr / 3), FIXED_NEW(127))) + 128)); + + colors[1] = ((FIXED_TO_INT(FIXED_MULT(FIXED_SIN(rr / 2), FIXED_NEW(127))) + 128) << 16) | + ((FIXED_TO_INT(FIXED_MULT(FIXED_COS(rr / 2), FIXED_NEW(127))) + 128)) << 8 | + ((FIXED_TO_INT(FIXED_MULT(FIXED_SIN(rr), FIXED_NEW(127))) + 128) ); + + /* The dimensions are cut in half and negated to center the rotation. */ + /* The [xy]_{sin,cos}_r variables are accumulators to replace multiplication with addition. */ + x_cos_r_init = FIXED_MULT(-FIXED_NEW((width / 2)), cos_r); + x_sin_r_init = FIXED_MULT(-FIXED_NEW((width / 2)), sin_r); + + y_cos_r = FIXED_MULT(-FIXED_NEW((height / 2)), cos_r); + y_sin_r = FIXED_MULT(-FIXED_NEW((height / 2)), sin_r); + + for (y = 0; y < height; y++) { + + x_cos_r = x_cos_r_init; + x_sin_r = x_sin_r_init; + + for (x = 0; x < width; x++, buf++) { + + tx = FIXED_TO_INT(x_sin_r - y_cos_r); + ty = FIXED_TO_INT(y_sin_r + x_cos_r); + + *buf = colors[texture[ty][tx]]; + + x_cos_r += cos_r; + x_sin_r += sin_r; + } + + buf += stride; + y_cos_r += cos_r; + y_sin_r += sin_r; + } + + // This governs the rotation and color cycle. + r += FIXED_TO_INT(FIXED_MULT(FIXED_SIN(rr), FIXED_NEW(16))); + rr += 2; +} + + +/* Draw a rotating checkered 256x256 texture into fragment. (64-bit version) */ +static void roto64(fb_fragment_t *fragment) +{ + static int32_t costab[FIXED_TRIG_LUT_SIZE], sintab[FIXED_TRIG_LUT_SIZE]; + static uint8_t texture[256][256]; + static int initialized; + static uint32_t colors[2]; + static unsigned r, rr; + + int y_cos_r, y_sin_r, x_cos_r, x_sin_r, x_cos_r_init, x_sin_r_init, cos_r, sin_r; + int x, y, stride = fragment->stride / 8, width = fragment->width, height = fragment->height; + uint8_t tx, ty; /* 256x256 texture; 8 bit texture indices to modulo via overflow. */ + uint64_t *buf = (uint64_t *)fragment->buf; + + if (!initialized) { + int i; + + initialized = 1; + + /* Generate simple checker pattern texture, nothing clever, feel free to play! */ + /* If you modify texture on every frame instead of only @ initialization you can + * produce some neat output. These values are indexed into colors[] below. */ + for (y = 0; y < 128; y++) { + for (x = 0; x < 128; x++) + texture[y][x] = 1; + for (; x < 256; x++) + texture[y][x] = 0; + } + for (; y < 256; y++) { + for (x = 0; x < 128; x++) + texture[y][x] = 0; + for (; x < 256; x++) + texture[y][x] = 1; + } + + /* Generate fixed-point cos & sin LUTs. */ + for (i = 0; i < FIXED_TRIG_LUT_SIZE; i++) { + costab[i] = ((cos((double)2*M_PI*i/FIXED_TRIG_LUT_SIZE))*FIXED_EXP); + sintab[i] = ((sin((double)2*M_PI*i/FIXED_TRIG_LUT_SIZE))*FIXED_EXP); + } + } + + /* This is all done using fixed-point in the hopes of being faster, and yes assumptions + * are being made WRT the overflow of tx/ty as well, only tested on x86_64. */ + cos_r = FIXED_COS(r); + sin_r = FIXED_SIN(r); + + /* Vary the colors, this is just a mashup of sinusoidal rgb values. */ + colors[0] = ((FIXED_TO_INT(FIXED_MULT(FIXED_COS(rr), FIXED_NEW(127))) + 128) << 16) | + ((FIXED_TO_INT(FIXED_MULT(FIXED_SIN(rr / 2), FIXED_NEW(127))) + 128) << 8) | + ((FIXED_TO_INT(FIXED_MULT(FIXED_COS(rr / 3), FIXED_NEW(127))) + 128)); + + colors[1] = ((FIXED_TO_INT(FIXED_MULT(FIXED_SIN(rr / 2), FIXED_NEW(127))) + 128) << 16) | + ((FIXED_TO_INT(FIXED_MULT(FIXED_COS(rr / 2), FIXED_NEW(127))) + 128)) << 8 | + ((FIXED_TO_INT(FIXED_MULT(FIXED_SIN(rr), FIXED_NEW(127))) + 128) ); + + /* The dimensions are cut in half and negated to center the rotation. */ + /* The [xy]_{sin,cos}_r variables are accumulators to replace multiplication with addition. */ + x_cos_r_init = FIXED_MULT(-FIXED_NEW((width / 2)), cos_r); + x_sin_r_init = FIXED_MULT(-FIXED_NEW((width / 2)), sin_r); + + y_cos_r = FIXED_MULT(-FIXED_NEW((height / 2)), cos_r); + y_sin_r = FIXED_MULT(-FIXED_NEW((height / 2)), sin_r); + + width /= 2; /* Since we're processing 64-bit words (2 pixels) at a time */ + + for (y = 0; y < height; y++) { + + x_cos_r = x_cos_r_init; + x_sin_r = x_sin_r_init; + + for (x = 0; x < width; x++, buf++) { + uint64_t p; + + tx = FIXED_TO_INT(x_sin_r - y_cos_r); + ty = FIXED_TO_INT(y_sin_r + x_cos_r); + + p = colors[texture[ty][tx]]; + + x_cos_r += cos_r; + x_sin_r += sin_r; + + tx = FIXED_TO_INT(x_sin_r - y_cos_r); + ty = FIXED_TO_INT(y_sin_r + x_cos_r); + + p |= (uint64_t)colors[texture[ty][tx]] << 32; + + *buf = p; + + x_cos_r += cos_r; + x_sin_r += sin_r; + } + + buf += stride; + y_cos_r += cos_r; + y_sin_r += sin_r; + } + + // This governs the rotation and color cycle. + r += FIXED_TO_INT(FIXED_MULT(FIXED_SIN(rr), FIXED_NEW(16))); + rr += 2; +} + + +rototiller_renderer_t roto32_renderer = { + .render = roto32, + .name = "roto32", + .description = "Tiled texture rotation (32-bit)", + .author = "Vito Caputo <vcaputo@pengaru.com>", + .license = "GPLv2", +}; + + +rototiller_renderer_t roto64_renderer = { + .render = roto64, + .name = "roto64", + .description = "Tiled texture rotation (64-bit)", + .author = "Vito Caputo <vcaputo@pengaru.com>", + .license = "GPLv2", +}; diff --git a/modules/roto/roto.h b/modules/roto/roto.h new file mode 100644 index 0000000..84a66a9 --- /dev/null +++ b/modules/roto/roto.h @@ -0,0 +1,9 @@ +#ifndef _ROTO_H +#define _ROTO_H + +#include "fb.h" + +void roto64(fb_fragment_t *fragment); +void roto32(fb_fragment_t *fragment); + +#endif diff --git a/modules/sparkler/bsp.c b/modules/sparkler/bsp.c new file mode 100644 index 0000000..6544993 --- /dev/null +++ b/modules/sparkler/bsp.c @@ -0,0 +1,556 @@ +#include <assert.h> +#include <stdio.h> +#include <stdint.h> +#include <stdlib.h> + +#include "bsp.h" + + +/* octree-based bsp for faster proximity searches */ +/* meanings: + * octrant = "octo" analog of a quadrant, an octree is a quadtree with an additional dimension (Z/3d) + * bv = bounding volume + * bsp = binary space partition + * occupant = the things being indexed by the bsp (e.g. a particle, or its position) + */ + + +/* FIXME: these are not tuned at all, and should really all be parameters to bsp_new() instead */ +#define BSP_GROWBY 16 +#define BSP_MAX_OCCUPANTS 64 +#define BSP_MAX_DEPTH 16 + +#define MAX(_a, _b) (_a > _b ? _a : _b) +#define MIN(_a, _b) (_a < _b ? _a : _b) + + +struct bsp_node_t { + v3f_t center; /* center point about which the bounding volume's 3d-space is divided */ + bsp_node_t *parent; /* parent bounding volume, NULL when root node */ + bsp_node_t *octrants; /* NULL when a leaf, otherwise an array of 8 bsp_node_t's */ + list_head_t occupants; /* list of occupants in this volume when a leaf node */ + unsigned n_occupants; /* number of ^^ */ +}; + + +struct bsp_t { + bsp_node_t root; + list_head_t free; +}; + + +#define OCTRANTS \ + octrant(OCT_XL_YL_ZL, (1 << 2 | 1 << 1 | 1)) \ + octrant(OCT_XR_YL_ZL, ( 1 << 1 | 1)) \ + octrant(OCT_XL_YR_ZL, (1 << 2 | 1)) \ + octrant(OCT_XR_YR_ZL, ( 1)) \ + octrant(OCT_XL_YL_ZR, (1 << 2 | 1 << 1 )) \ + octrant(OCT_XR_YL_ZR, ( 1 << 1 )) \ + octrant(OCT_XL_YR_ZR, (1 << 2 )) \ + octrant(OCT_XR_YR_ZR, 0) + + +#define octrant(_sym, _val) _sym = _val, +typedef enum _octrant_idx_t { + OCTRANTS +} octrant_idx_t; +#undef octrant + + + +static inline const char * octstr(octrant_idx_t oidx) +{ +#define octrant(_sym, _val) #_sym, + static const char *octrant_strs[] = { + OCTRANTS + }; +#undef octrant + + return octrant_strs[oidx]; +} + + +static inline void _bsp_print(bsp_node_t *node) +{ + static int depth = 0; + + fprintf(stderr, "%-*s %i: %p\n", depth, " ", depth, node); + if (node->octrants) { + int i; + + for (i = 0; i < 8; i++) { + fprintf(stderr, "%-*s %i: %s: %p\n", depth, " ", depth, octstr(i), &node->octrants[i]); + depth++; + _bsp_print(&node->octrants[i]); + depth--; + } + } +} + + +/* Print a bsp tree to stderr (debugging) */ +void bsp_print(bsp_t *bsp) +{ + _bsp_print(&bsp->root); +} + + +/* Create a new bsp octree. */ +bsp_t * bsp_new(void) +{ + bsp_t *bsp; + + bsp = calloc(1, sizeof(bsp_t)); + if (!bsp) { + return NULL; + } + + INIT_LIST_HEAD(&bsp->root.occupants); + INIT_LIST_HEAD(&bsp->free); + + return bsp; +} + + +/* Free a bsp octree */ +void bsp_free(bsp_t *bsp) +{ + /* TODO: free everything ... */ + free(bsp); +} + + +/* bsp lookup state, encapsulated for preservation across composite + * lookup-dependent operations, so they can potentially avoid having + * to redo the lookup. i.e. lookup caching. + */ +typedef struct _bsp_lookup_t { + int depth; + v3f_t left; + v3f_t right; + bsp_node_t *bv; + octrant_idx_t oidx; +} bsp_lookup_t; + +/* lookup a position's containing leaf node in the bsp tree, store resultant lookup state in *lookup_res */ +static inline void bsp_lookup_position(bsp_node_t *root, v3f_t *position, bsp_lookup_t *lookup_res) +{ + bsp_lookup_t res = { + .bv = root, + .depth = 0, + .left = v3f_init(-1.0, -1.0, -1.0), /* TODO: the bsp AABB should be supplied to bsp_new() */ + .right = v3f_init(1.0, 1.0, 1.0), + }; + + while (res.bv->octrants) { + res.oidx = OCT_XR_YR_ZR; + if (position->x <= res.bv->center.x) { + res.oidx |= (1 << 2); + res.right.x = res.bv->center.x; + } else { + res.left.x = res.bv->center.x; + } + + if (position->y <= res.bv->center.y) { + res.oidx |= (1 << 1); + res.right.y = res.bv->center.y; + } else { + res.left.y = res.bv->center.y; + } + + if (position->z <= res.bv->center.z) { + res.oidx |= 1; + res.right.z = res.bv->center.z; + } else { + res.left.z = res.bv->center.z; + } + + res.bv = &res.bv->octrants[res.oidx]; + res.depth++; + } + + *lookup_res = res; +} + + +/* Add an occupant to a bsp tree, use provided node lookup *l if supplied */ +static inline void _bsp_add_occupant(bsp_t *bsp, bsp_occupant_t *occupant, v3f_t *position, bsp_lookup_t *l) +{ + bsp_lookup_t _lookup; + + /* if no cached lookup result was provided, perform the lookup now. */ + if (!l) { + l = &_lookup; + bsp_lookup_position(&bsp->root, position, l); + } + + assert(l); + assert(l->bv); + + occupant->position = position; + +#define map_occupant2octrant(_occupant, _bv, _octrant) \ + _octrant = OCT_XR_YR_ZR; \ + if (_occupant->position->x <= _bv->center.x) { \ + _octrant |= (1 << 2); \ + } \ + if (_occupant->position->y <= _bv->center.y) { \ + _octrant |= (1 << 1); \ + } \ + if (_occupant->position->z <= _bv->center.z) { \ + _octrant |= 1; \ + } + + if (l->bv->n_occupants >= BSP_MAX_OCCUPANTS && l->depth < BSP_MAX_DEPTH) { + int i; + list_head_t *t, *_t; + bsp_node_t *bv = l->bv; + + /* bv is full and shallow enough, subdivide it. */ + + /* ensure the free list has something for us */ + if (list_empty(&bsp->free)) { + bsp_node_t *t; + + /* TODO: does using the chunker instead make sense here? */ + t = calloc(sizeof(bsp_node_t), 8 * BSP_GROWBY); + for (i = 0; i < 8 * BSP_GROWBY; i += 8) { + list_add(&t[i].occupants, &bsp->free); + } + } + + /* take an octrants array from the free list */ + bv->octrants = list_entry(bsp->free.next, bsp_node_t, occupants); + list_del(&bv->octrants[0].occupants); + + /* initialize the octrants */ + for (i = 0; i < 8; i++) { + INIT_LIST_HEAD(&bv->octrants[i].occupants); + bv->octrants[i].n_occupants = 0; + bv->octrants[i].parent = bv; + bv->octrants[i].octrants = NULL; + } + + /* set the center point in each octrant which places the partitioning hyperplane */ + /* XXX: note this is pretty unreadable due to reusing the earlier computed values + * where the identical computation is required. + */ + bv->octrants[OCT_XR_YR_ZR].center.x = (l->right.x - bv->center.x) / 2 + bv->center.x; + bv->octrants[OCT_XR_YR_ZR].center.y = (l->right.y - bv->center.y) / 2 + bv->center.y; + bv->octrants[OCT_XR_YR_ZR].center.z = (l->right.z - bv->center.z) / 2 + bv->center.z; + + bv->octrants[OCT_XR_YR_ZL].center.x = bv->octrants[OCT_XR_YR_ZR].center.x; + bv->octrants[OCT_XR_YR_ZL].center.y = bv->octrants[OCT_XR_YR_ZR].center.y; + bv->octrants[OCT_XR_YR_ZL].center.z = (bv->center.z - l->left.z) / 2 + l->left.z; + + bv->octrants[OCT_XR_YL_ZR].center.x = bv->octrants[OCT_XR_YR_ZR].center.x; + bv->octrants[OCT_XR_YL_ZR].center.y = (bv->center.y - l->left.y) / 2 + l->left.y; + bv->octrants[OCT_XR_YL_ZR].center.z = bv->octrants[OCT_XR_YR_ZR].center.z; + + bv->octrants[OCT_XR_YL_ZL].center.x = bv->octrants[OCT_XR_YR_ZR].center.x; + bv->octrants[OCT_XR_YL_ZL].center.y = bv->octrants[OCT_XR_YL_ZR].center.y; + bv->octrants[OCT_XR_YL_ZL].center.z = bv->octrants[OCT_XR_YR_ZL].center.z; + + bv->octrants[OCT_XL_YR_ZR].center.x = (bv->center.x - l->left.x) / 2 + l->left.x; + bv->octrants[OCT_XL_YR_ZR].center.y = bv->octrants[OCT_XR_YR_ZR].center.y; + bv->octrants[OCT_XL_YR_ZR].center.z = bv->octrants[OCT_XR_YR_ZR].center.z; + + bv->octrants[OCT_XL_YR_ZL].center.x = bv->octrants[OCT_XL_YR_ZR].center.x; + bv->octrants[OCT_XL_YR_ZL].center.y = bv->octrants[OCT_XR_YR_ZR].center.y; + bv->octrants[OCT_XL_YR_ZL].center.z = bv->octrants[OCT_XR_YR_ZL].center.z; + + bv->octrants[OCT_XL_YL_ZR].center.x = bv->octrants[OCT_XL_YR_ZR].center.x; + bv->octrants[OCT_XL_YL_ZR].center.y = bv->octrants[OCT_XR_YL_ZR].center.y; + bv->octrants[OCT_XL_YL_ZR].center.z = bv->octrants[OCT_XR_YR_ZR].center.z; + + bv->octrants[OCT_XL_YL_ZL].center.x = bv->octrants[OCT_XL_YR_ZR].center.x; + bv->octrants[OCT_XL_YL_ZL].center.y = bv->octrants[OCT_XR_YL_ZR].center.y; + bv->octrants[OCT_XL_YL_ZL].center.z = bv->octrants[OCT_XR_YR_ZL].center.z; + + /* migrate the occupants into the appropriate octrants */ + list_for_each_safe(t, _t, &bv->occupants) { + octrant_idx_t oidx; + bsp_occupant_t *o = list_entry(t, bsp_occupant_t, occupants); + + map_occupant2octrant(o, bv, oidx); + list_move(t, &bv->octrants[oidx].occupants); + o->leaf = &bv->octrants[oidx]; + bv->octrants[oidx].n_occupants++; + } + bv->n_occupants = 0; + + /* a new leaf assumes the bv position for the occupant to be added into */ + map_occupant2octrant(occupant, bv, l->oidx); + l->bv = &bv->octrants[l->oidx]; + l->depth++; + } + +#undef map_occupant2octrant + + occupant->leaf = l->bv; + list_add(&occupant->occupants, &l->bv->occupants); + l->bv->n_occupants++; + + assert(occupant->leaf); +} + + +/* add an occupant to a bsp tree */ +void bsp_add_occupant(bsp_t *bsp, bsp_occupant_t *occupant, v3f_t *position) +{ + _bsp_add_occupant(bsp, occupant, position, NULL); +} + + +/* Delete an occupant from a bsp tree. + * Set reservation to prevent potentially freeing a node made empty by our delete that + * we have a reference to (i.e. a cached lookup result, see bsp_move_occupant()). + */ +static inline void _bsp_delete_occupant(bsp_t *bsp, bsp_occupant_t *occupant, bsp_node_t *reservation) +{ + if (occupant->leaf->octrants) { + fprintf(stderr, "BUG: deleting occupant(%p) from non-leaf bv(%p)\n", occupant, occupant->leaf); + } + + /* delete the occupant */ + list_del(&occupant->occupants); + occupant->leaf->n_occupants--; + + if (list_empty(&occupant->leaf->occupants)) { + bsp_node_t *parent_bv; + + if (occupant->leaf->n_occupants) { + fprintf(stderr, "BUG: bv_occupants empty but n_occupants=%u\n", occupant->leaf->n_occupants); + } + + /* leaf is now empty, since nodes are allocated as clusters of 8, they aren't freed unless all nodes in the cluster are empty. + * Determine if they're all empty, and free the parent's octrants as a set. + * Repeat this process up the chain of parents, repeatedly converting empty parents into leaf nodes. + * TODO: maybe just use the chunker instead? + */ + + for (parent_bv = occupant->leaf->parent; parent_bv && parent_bv != reservation; parent_bv = parent_bv->parent) { + int i; + + /* are _all_ the parent's octrants freeable? */ + for (i = 0; i < 8; i++) { + if (&parent_bv->octrants[i] == reservation || + parent_bv->octrants[i].octrants || + !list_empty(&parent_bv->octrants[i].occupants)) { + goto _out; + } + } + + /* "freeing" really just entails putting the octrants cluster of nodes onto the free list */ + list_add(&parent_bv->octrants[0].occupants, &bsp->free); + parent_bv->octrants = NULL; + } + } + +_out: + occupant->leaf = NULL; +} + + +/* Delete an occupant from a bsp tree. */ +void bsp_delete_occupant(bsp_t *bsp, bsp_occupant_t *occupant) +{ + _bsp_delete_occupant(bsp, occupant, NULL); +} + + +/* Move an occupant within a bsp tree to a new position */ +void bsp_move_occupant(bsp_t *bsp, bsp_occupant_t *occupant, v3f_t *position) +{ + bsp_lookup_t lookup_res; + + if (v3f_equal(occupant->position, position)) { + return; + } + + bsp_lookup_position(&bsp->root, occupant->position, &lookup_res); + if (lookup_res.bv == occupant->leaf) { + /* leaf unchanged, do nothing past lookup. */ + occupant->position = position; + return; + } + + _bsp_delete_occupant(bsp, occupant, lookup_res.bv); + _bsp_add_occupant(bsp, occupant, position, &lookup_res); +} + + +static inline float square(float v) +{ + return v * v; +} + + +typedef enum overlaps_t { + OVERLAPS_NONE, /* objects are completely separated */ + OVERLAPS_PARTIALLY, /* objects surfaces one another */ + OVERLAPS_A_IN_B, /* first object is fully within the second */ + OVERLAPS_B_IN_A, /* second object is fully within the first */ +} overlaps_t; + + +/* Returns wether the axis-aligned bounding box (AABB) overlaps the sphere. + * Absolute vs. partial overlaps are distinguished, since it's an important optimization + * to know if the sphere falls entirely within one partition of the octree. + */ +static inline overlaps_t aabb_overlaps_sphere(v3f_t *aabb_min, v3f_t *aabb_max, v3f_t *sphere_center, float sphere_radius) +{ + /* This implementation is based on James Arvo's from Graphics Gems pg. 335 */ + float r2 = square(sphere_radius); + float dface = INFINITY; + float dmin = 0; + float dmax = 0; + float a, b; + +#define per_dimension(_center, _box_max, _box_min) \ + a = square(_center - _box_min); \ + b = square(_center - _box_max); \ + \ + dmax += MAX(a, b); \ + if (_center >= _box_min && _center <= _box_max) { \ + /* sphere center within box */ \ + dface = MIN(dface, MIN(a, b)); \ + } else { \ + /* sphere center outside the box */ \ + dface = 0; \ + dmin += MIN(a, b); \ + } + + per_dimension(sphere_center->x, aabb_max->x, aabb_min->x); + per_dimension(sphere_center->y, aabb_max->y, aabb_min->y); + per_dimension(sphere_center->z, aabb_max->z, aabb_min->z); + + if (dmax < r2) { + /* maximum distance to box smaller than radius, box is inside + * the sphere */ + return OVERLAPS_A_IN_B; + } + + if (dface > r2) { + /* sphere center is within box (non-zero dface), and dface is + * greater than sphere diameter, sphere is inside the box. */ + return OVERLAPS_B_IN_A; + } + + if (dmin <= r2) { + /* minimum distance from sphere center to box is smaller than + * sphere's radius, surfaces intersect */ + return OVERLAPS_PARTIALLY; + } + + return OVERLAPS_NONE; +} + + +typedef struct bsp_search_sphere_t { + v3f_t *center; + float radius_min; + float radius_max; + void (*cb)(bsp_t *, list_head_t *, void *); + void *cb_data; +} bsp_search_sphere_t; + + +static overlaps_t _bsp_search_sphere(bsp_t *bsp, bsp_node_t *node, bsp_search_sphere_t *search, v3f_t *aabb_min, v3f_t *aabb_max) +{ + overlaps_t res; + v3f_t oaabb_min, oaabb_max; + + /* if the radius_max search doesn't overlap aabb_min:aabb_max at all, simply return. */ + res = aabb_overlaps_sphere(aabb_min, aabb_max, search->center, search->radius_max); + if (res == OVERLAPS_NONE) { + return res; + } + + /* if the radius_max absolutely overlaps the AABB, we must see if the AABB falls entirely within radius_min so we can skip it. */ + if (res == OVERLAPS_A_IN_B) { + res = aabb_overlaps_sphere(aabb_min, aabb_max, search->center, search->radius_min); + if (res == OVERLAPS_A_IN_B) { + /* AABB is entirely within radius_min, skip it. */ + return OVERLAPS_NONE; + } + + if (res == OVERLAPS_NONE) { + /* radius_min didn't overlap, radius_max overlapped aabb 100%, it's entirely within the range. */ + res = OVERLAPS_A_IN_B; + } else { + /* radius_min overlapped partially.. */ + res = OVERLAPS_PARTIALLY; + } + } + + /* if node is a leaf, call search->cb with the occupants, then return. */ + if (!node->octrants) { + search->cb(bsp, &node->occupants, search->cb_data); + return res; + } + + /* node is a parent, recur on each octrant with appropriately adjusted aabb_min:aabb_max values */ + /* if any of the octrants absolutely overlaps the search sphere, skip the others by returning. */ +#define search_octrant(_oid, _aabb_min, _aabb_max) \ + res = _bsp_search_sphere(bsp, &node->octrants[_oid], search, _aabb_min, _aabb_max); \ + if (res == OVERLAPS_B_IN_A) { \ + return res; \ + } + + /* OCT_XL_YL_ZL and OCT_XR_YR_ZR AABBs don't require tedious composition */ + search_octrant(OCT_XL_YL_ZL, aabb_min, &node->center); + search_octrant(OCT_XR_YR_ZR, &node->center, aabb_max); + + /* the rest are stitched together requiring temp storage and tedium */ + v3f_set(&oaabb_min, node->center.x, aabb_min->y, aabb_min->z); + v3f_set(&oaabb_max, aabb_max->x, node->center.y, node->center.z); + search_octrant(OCT_XR_YL_ZL, &oaabb_min, &oaabb_max); + + v3f_set(&oaabb_min, aabb_min->x, node->center.y, aabb_min->z); + v3f_set(&oaabb_max, node->center.x, aabb_max->y, node->center.z); + search_octrant(OCT_XL_YR_ZL, &oaabb_min, &oaabb_max); + + v3f_set(&oaabb_min, node->center.x, node->center.y, aabb_min->z); + v3f_set(&oaabb_max, aabb_max->x, aabb_max->y, node->center.z); + search_octrant(OCT_XR_YR_ZL, &oaabb_min, &oaabb_max); + + v3f_set(&oaabb_min, aabb_min->x, aabb_min->y, node->center.z); + v3f_set(&oaabb_max, node->center.x, node->center.y, aabb_max->z); + search_octrant(OCT_XL_YL_ZR, &oaabb_min, &oaabb_max); + + v3f_set(&oaabb_min, node->center.x, aabb_min->y, node->center.z); + v3f_set(&oaabb_max, aabb_max->x, node->center.y, aabb_max->z); + search_octrant(OCT_XR_YL_ZR, &oaabb_min, &oaabb_max); + + v3f_set(&oaabb_min, aabb_min->x, node->center.y, node->center.z); + v3f_set(&oaabb_max, node->center.x, aabb_max->y, aabb_max->z); + search_octrant(OCT_XL_YR_ZR, &oaabb_min, &oaabb_max); + +#undef search_octrant + + /* since early on an OVERLAPS_NONE short-circuits the function, and + * OVERLAPS_ABSOLUTE also causes short-circuits, if we arrive here it's + * a partial overlap + */ + return OVERLAPS_PARTIALLY; +} + + +/* search the bsp tree for leaf nodes which intersect the space between radius_min and radius_max of a sphere @ center */ +/* for every leaf node found to intersect the sphere, cb is called with the leaf node's occupants list head */ +/* the callback cb must then further filter the occupants as necessary. */ +void bsp_search_sphere(bsp_t *bsp, v3f_t *center, float radius_min, float radius_max, void (*cb)(bsp_t *, list_head_t *, void *), void *cb_data) +{ + bsp_search_sphere_t search = { + .center = center, + .radius_min = radius_min, + .radius_max = radius_max, + .cb = cb, + .cb_data = cb_data, + }; + v3f_t aabb_min = v3f_init(-1.0f, -1.0f, -1.0f); + v3f_t aabb_max = v3f_init(1.0f, 1.0f, 1.0f); + + _bsp_search_sphere(bsp, &bsp->root, &search, &aabb_min, &aabb_max); +} diff --git a/modules/sparkler/bsp.h b/modules/sparkler/bsp.h new file mode 100644 index 0000000..f5ce303 --- /dev/null +++ b/modules/sparkler/bsp.h @@ -0,0 +1,28 @@ +#ifndef _BSP_H +#define _BSP_H + +#include <stdint.h> + +#include "list.h" +#include "v3f.h" + +typedef struct bsp_t bsp_t; +typedef struct bsp_node_t bsp_node_t; + +/* Embed this in anything you want spatially indexed by the bsp tree. */ +/* TODO: it would be nice to make this opaque, but it's a little annoying. */ +typedef struct bsp_occupant_t { + bsp_node_t *leaf; /* leaf node containing this occupant */ + list_head_t occupants; /* node on containing leaf node's list of occupants */ + v3f_t *position; /* position of occupant to be partitioned */ +} bsp_occupant_t; + +bsp_t * bsp_new(void); +void bsp_free(bsp_t *bsp); +void bsp_print(bsp_t *bsp); +void bsp_add_occupant(bsp_t *bsp, bsp_occupant_t *occupant, v3f_t *position); +void bsp_delete_occupant(bsp_t *bsp, bsp_occupant_t *occupant); +void bsp_move_occupant(bsp_t *bsp, bsp_occupant_t *occupant, v3f_t *position); +void bsp_search_sphere(bsp_t *bsp, v3f_t *center, float radius_min, float radius_max, void (*cb)(bsp_t *, list_head_t *, void *), void *cb_data); + +#endif diff --git a/modules/sparkler/burst.c b/modules/sparkler/burst.c new file mode 100644 index 0000000..828ca02 --- /dev/null +++ b/modules/sparkler/burst.c @@ -0,0 +1,111 @@ +#include <stdlib.h> + +#include "bsp.h" +#include "container.h" +#include "particle.h" +#include "particles.h" + + +/* a "burst" (shockwave) particle type */ +/* this doesn't draw anything, it just pushes neighbors away in an increasing radius */ + +#define BURST_FORCE 0.01f +#define BURST_MAX_LIFETIME 8 + +typedef struct _burst_ctxt_t { + int longevity; + int lifetime; +} burst_ctxt_t; + + +static int burst_init(particles_t *particles, particle_t *p) +{ + burst_ctxt_t *ctxt = p->ctxt; + + ctxt->longevity = ctxt->lifetime = BURST_MAX_LIFETIME; + p->props->velocity = 0; /* burst should be stationary */ + p->props->mass = 0; /* no mass prevents gravity's effects */ + + return 1; +} + + +static inline void thrust_part(particle_t *burst, particle_t *victim, float distance_sq) +{ + v3f_t direction = v3f_sub(&victim->props->position, &burst->props->position); + + /* TODO: normalize is expensive, see about removing these. */ + direction = v3f_normalize(&direction); + victim->props->direction = v3f_add(&victim->props->direction, &direction); + victim->props->direction = v3f_normalize(&victim->props->direction); + + victim->props->velocity += BURST_FORCE; +} + + +typedef struct burst_sphere_t { + particle_t *center; + float radius_min; + float radius_max; +} burst_sphere_t; + + +static void burst_cb(bsp_t *bsp, list_head_t *occupants, void *_s) +{ + burst_sphere_t *s = _s; + bsp_occupant_t *o; + float rmin_sq = s->radius_min * s->radius_min; + float rmax_sq = s->radius_max * s->radius_max; + + /* XXX: to avoid having a callback per-particle, bsp_occupant_t was + * moved to the public particle, and the particle-specific + * implementations directly perform bsp-accelerated searches. Another + * wart caused by this is particles_bsp(). + */ + list_for_each_entry(o, occupants, occupants) { + particle_t *p = container_of(o, particle_t, occupant); + float d_sq; + + if (p == s->center) { + /* leave ourselves alone */ + continue; + } + + d_sq = v3f_distance_sq(&s->center->props->position, &p->props->position); + + if (d_sq > rmin_sq && d_sq < rmax_sq) { + /* displace the part relative to the burst origin */ + thrust_part(s->center, p, d_sq); + } + + } +} + + +static particle_status_t burst_sim(particles_t *particles, particle_t *p) +{ + burst_ctxt_t *ctxt = p->ctxt; + bsp_t *bsp = particles_bsp(particles); /* XXX see note above about bsp_occupant_t */ + burst_sphere_t s; + + if (!ctxt->longevity || (ctxt->longevity--) <= 0) { + return PARTICLE_DEAD; + } + + /* affect neighbors for the shock-wave */ + s.radius_min = (1.0f - ((float)ctxt->longevity / ctxt->lifetime)) * 0.075f; + s.radius_max = s.radius_min + .01f; + s.center = p; + bsp_search_sphere(bsp, &p->props->position, s.radius_min, s.radius_max, burst_cb, &s); + + return PARTICLE_ALIVE; +} + + +particle_ops_t burst_ops = { + .context_size = sizeof(burst_ctxt_t), + .sim = burst_sim, + .init = burst_init, + .draw = NULL, + .cleanup = NULL, + }; diff --git a/modules/sparkler/chunker.c b/modules/sparkler/chunker.c new file mode 100644 index 0000000..ca072eb --- /dev/null +++ b/modules/sparkler/chunker.c @@ -0,0 +1,225 @@ +#include <assert.h> +#include <stddef.h> +#include <stdlib.h> +#include <stdint.h> +#include <string.h> + +#include "chunker.h" +#include "container.h" +#include "list.h" + +/* Everything associated with the particles tends to be short-lived. + * + * They come and go frequently in large numbers. This implements a very basic + * chunked allocator which prioritizes efficient allocation and freeing over + * low waste of memory. We malloc chunks at a time, doling out elements from + * the chunk sequentially as requested until the chunk is cannot fulfill an + * allocation, then we just retire the chunk, add a new chunk and continue. + * + * When allocations are freed, we simply decrement the refcount for its chunk, + * leaving the chunk pinned with holes accumulating until its refcount reaches + * zero, at which point the chunk is made available for allocations again. + * + * This requires a reference to the chunk be returned with every allocation. + * It may be possible to reduce the footprint of this by using a relative + * offset to the chunk start instead, but that would probably be more harmful + * to the alignment. + * + * This has some similarities to a slab allocator... + */ + +#define CHUNK_ALIGNMENT 8192 /* XXX: this may be unnecessary, callers should be able to ideally size their chunkers */ +#define ALLOC_ALIGNMENT 8 /* allocations within the chunk need to be aligned since their size affects subsequent allocation offsets */ +#define ALIGN(_size, _alignment) (((_size) + _alignment - 1) & ~(_alignment - 1)) + +typedef struct chunk_t { + chunker_t *chunker; /* chunker chunk belongs to */ + list_head_t chunks; /* node on free/pinned list */ + uint32_t n_refs; /* number of references (allocations) to this chunk */ + unsigned next_offset; /* next available offset for allocation */ + uint8_t mem[]; /* usable memory from this chunk */ +} chunk_t; + +typedef struct allocation_t { + chunk_t *chunk; /* chunk this allocation came from */ + uint8_t mem[]; /* usable memory from this allocation */ +} allocation_t; + +struct chunker_t { + chunk_t *chunk; /* current chunk allocations come from */ + unsigned chunk_size; /* size chunks are allocated in */ + list_head_t free_chunks; /* list of completely free chunks */ + list_head_t pinned_chunks; /* list of chunks pinned because they have an outstanding allocation */ +}; + + +/* Add a reference to a chunk. */ +static inline void chunk_ref(chunk_t *chunk) +{ + assert(chunk); + assert(chunk->chunker); + + chunk->n_refs++; + + assert(chunk->n_refs != 0); +} + + +/* Remove reference from a chunk, move to free list when no references remain. */ +static inline void chunk_unref(chunk_t *chunk) +{ + assert(chunk); + assert(chunk->chunker); + assert(chunk->n_refs > 0); + + chunk->n_refs--; + if (chunk->n_refs == 0) { + list_move(&chunk->chunks, &chunk->chunker->free_chunks); + } +} + + +/* Return allocated size of the chunk */ +static inline unsigned chunk_alloc_size(chunker_t *chunker) +{ + assert(chunker); + + return (sizeof(chunk_t) + chunker->chunk_size); +} + + +/* Get a new working chunk, retiring and replacing chunker->chunk. */ +static void chunker_new_chunk(chunker_t *chunker) +{ + chunk_t *chunk; + + assert(chunker); + + if (chunker->chunk) { + chunk_unref(chunker->chunk); + chunker->chunk = NULL; + } + + if (!list_empty(&chunker->free_chunks)) { + chunk = list_entry(chunker->free_chunks.next, chunk_t, chunks); + list_del(&chunk->chunks); + } else { + /* No free chunks, must ask libc for memory */ + chunk = malloc(chunk_alloc_size(chunker)); + } + + /* Note a chunk is pinned from the moment it's created, and a reference + * is added to represent chunker->chunk, even though no allocations + * occurred yet. + */ + chunk->n_refs = 1; + chunk->next_offset = 0; + chunk->chunker = chunker; + chunker->chunk = chunk; + list_add(&chunk->chunks, &chunker->pinned_chunks); +} + + +/* Create a new chunker. */ +chunker_t * chunker_new(unsigned chunk_size) +{ + chunker_t *chunker; + + chunker = calloc(1, sizeof(chunker_t)); + if (!chunker) { + return NULL; + } + + INIT_LIST_HEAD(&chunker->free_chunks); + INIT_LIST_HEAD(&chunker->pinned_chunks); + + /* XXX: chunker->chunk_size does not include the size of the chunk_t container */ + chunker->chunk_size = ALIGN(chunk_size, CHUNK_ALIGNMENT); + + return chunker; +} + + +/* Allocate non-zeroed memory from a chunker. */ +void * chunker_alloc(chunker_t *chunker, unsigned size) +{ + allocation_t *allocation; + + assert(chunker); + assert(size <= chunker->chunk_size); + + size = ALIGN(sizeof(allocation_t) + size, ALLOC_ALIGNMENT); + + if (!chunker->chunk || size + chunker->chunk->next_offset > chunker->chunk_size) { + /* Retire this chunk, time for a new one */ + chunker_new_chunk(chunker); + } + + if (!chunker->chunk) { + return NULL; + } + + chunk_ref(chunker->chunk); + allocation = (allocation_t *)&chunker->chunk->mem[chunker->chunk->next_offset]; + chunker->chunk->next_offset += size; + allocation->chunk = chunker->chunk; + + assert(chunker->chunk->next_offset <= chunker->chunk_size); + + return allocation->mem; +} + + +/* Free memory allocated from a chunker. */ +void chunker_free(void *ptr) +{ + allocation_t *allocation = container_of(ptr, allocation_t, mem); + + assert(ptr); + + chunk_unref(allocation->chunk); +} + + +/* Free a chunker and it's associated allocations. */ +void chunker_free_chunker(chunker_t *chunker) +{ + chunk_t *chunk, *_chunk; + + assert(chunker); + + if (chunker->chunk) { + chunk_unref(chunker->chunk); + } + + assert(list_empty(&chunker->pinned_chunks)); + + list_for_each_entry_safe(chunk, _chunk, &chunker->free_chunks, chunks) { + free(chunk); + } + + free(chunker); +} + +/* TODO: add pinned chunk iterator interface for cache-friendly iterating across + * chunk contents. + * The idea is that at times when the performance is really important, the + * chunks will be full of active particles, because it's the large numbers + * which slows us down. At those times, it's beneficial to not walk linked + * lists of structs to process them, instead we just process all the elements + * of the chunk as an array and assume everything is active. The type of + * processing being done in this fashion is benign to perform on an unused + * element, as long as there's no dangling pointers being dereferenced. If + * there's references, a status field could be maintained in the entry to say + * if it's active, then simply skip processing of the inactive elements. This + * tends to be more cache-friendly than chasing pointers. A linked list + * heirarchy of particles is still maintained for the parent:child + * relationships under the assumption that some particles will make use of the + * tracked descendants, though nothing has been done with it yet. + * + * The current implementation of the _particle_t is variable length, which precludes + * this optimization. However, breaking out the particle_props_t into a separate + * chunker would allow running particles_age() across the props alone directly + * within the pinned chunks. The other passes are still done heirarchically, + * and require the full particle context. + */ diff --git a/modules/sparkler/chunker.h b/modules/sparkler/chunker.h new file mode 100644 index 0000000..ac53cec --- /dev/null +++ b/modules/sparkler/chunker.h @@ -0,0 +1,11 @@ +#ifndef _CHUNKER_H +#define _CHUNKER_H + +typedef struct chunker_t chunker_t; + +chunker_t * chunker_new(unsigned chunk_size); +void * chunker_alloc(chunker_t *chunker, unsigned size); +void chunker_free(void *mem); +void chunker_free_chunker(chunker_t *chunker); + +#endif diff --git a/modules/sparkler/container.h b/modules/sparkler/container.h new file mode 100644 index 0000000..a3779e8 --- /dev/null +++ b/modules/sparkler/container.h @@ -0,0 +1,11 @@ +#ifndef _CONTAINER_H +#define _CONTAINER_H + +#include <stddef.h> + +#ifndef container_of +#define container_of(_ptr, _type, _member) \ + (_type *)((void *)(_ptr) - offsetof(_type, _member)) +#endif + +#endif diff --git a/modules/sparkler/draw.h b/modules/sparkler/draw.h new file mode 100644 index 0000000..58a4a36 --- /dev/null +++ b/modules/sparkler/draw.h @@ -0,0 +1,32 @@ +#ifndef _DRAW_H +#define _DRAW_H + +#include <stdint.h> + +#include "fb.h" + +/* helper for scaling rgb colors and packing them into an pixel */ +static inline uint32_t makergb(uint32_t r, uint32_t g, uint32_t b, float intensity) +{ + r = (((float)intensity) * r); + g = (((float)intensity) * g); + b = (((float)intensity) * b); + + return (((r & 0xff) << 16) | ((g & 0xff) << 8) | (b & 0xff)); +} + +static inline int draw_pixel(fb_fragment_t *f, int x, int y, uint32_t pixel) +{ + uint32_t *pixels = f->buf; + + if (y < 0 || y >= f->height || x < 0 || x >= f->width) { + return 0; + } + + /* FIXME this assumes stride is aligned to 4 */ + pixels[(y * f->width + (f->stride >> 2)) + x] = pixel; + + return 1; +} + +#endif diff --git a/modules/sparkler/list.h b/modules/sparkler/list.h new file mode 100644 index 0000000..48bca36 --- /dev/null +++ b/modules/sparkler/list.h @@ -0,0 +1,252 @@ +#ifndef __LIST_H +#define __LIST_H + +/* linux kernel linked list interface */ + +/* + * Simple doubly linked list implementation. + * + * Some of the internal functions ("__xxx") are useful when + * manipulating whole lists rather than single entries, as + * sometimes we already know the next/prev entries and we can + * generate better code by using them directly rather than + * using the generic single-entry routines. + */ + +typedef struct list_head { + struct list_head *next, *prev; +} list_head_t; + +#define LIST_HEAD_INIT(name) { &(name), &(name) } + +#define LIST_HEAD(name) \ + struct list_head name = LIST_HEAD_INIT(name) + +#define INIT_LIST_HEAD(ptr) do { \ + (ptr)->next = (ptr); (ptr)->prev = (ptr); \ +} while (0) + +/* + * Insert a new entry between two known consecutive entries. + * + * This is only for internal list manipulation where we know + * the prev/next entries already! + */ +static inline void __list_add(struct list_head *new, + struct list_head *prev, + struct list_head *next) +{ + next->prev = new; + new->next = next; + new->prev = prev; + prev->next = new; +} + +/** + * list_add - add a new entry + * @new: new entry to be added + * @head: list head to add it after + * + * Insert a new entry after the specified head. + * This is good for implementing stacks. + */ +static inline void list_add(struct list_head *new, struct list_head *head) +{ + __list_add(new, head, head->next); +} + +/** + * list_add_tail - add a new entry + * @new: new entry to be added + * @head: list head to add it before + * + * Insert a new entry before the specified head. + * This is useful for implementing queues. + */ +static inline void list_add_tail(struct list_head *new, struct list_head *head) +{ + __list_add(new, head->prev, head); +} + +/* + * Delete a list entry by making the prev/next entries + * point to each other. + * + * This is only for internal list manipulation where we know + * the prev/next entries already! + */ +static inline void __list_del(struct list_head *prev, struct list_head *next) +{ + next->prev = prev; + prev->next = next; +} + +/** + * list_del - deletes entry from list. + * @entry: the element to delete from the list. + * Note: list_empty on entry does not return true after this, the entry is in an undefined state. + */ +static inline void list_del(struct list_head *entry) +{ + __list_del(entry->prev, entry->next); + entry->next = (void *) 0; + entry->prev = (void *) 0; +} + +/** + * list_del_init - deletes entry from list and reinitialize it. + * @entry: the element to delete from the list. + */ +static inline void list_del_init(struct list_head *entry) +{ + __list_del(entry->prev, entry->next); + INIT_LIST_HEAD(entry); +} + +/** + * list_move - delete from one list and add as another's head + * @list: the entry to move + * @head: the head that will precede our entry + */ +static inline void list_move(struct list_head *list, struct list_head *head) +{ + __list_del(list->prev, list->next); + list_add(list, head); +} + +/** + * list_move_tail - delete from one list and add as another's tail + * @list: the entry to move + * @head: the head that will follow our entry + */ +static inline void list_move_tail(struct list_head *list, + struct list_head *head) +{ + __list_del(list->prev, list->next); + list_add_tail(list, head); +} + +/** + * list_empty - tests whether a list is empty + * @head: the list to test. + */ +static inline int list_empty(struct list_head *head) +{ + return head->next == head; +} + +static inline void __list_splice(struct list_head *list, + struct list_head *head) +{ + struct list_head *first = list->next; + struct list_head *last = list->prev; + struct list_head *at = head->next; + + first->prev = head; + head->next = first; + + last->next = at; + at->prev = last; +} + +/** + * list_splice - join two lists + * @list: the new list to add. + * @head: the place to add it in the first list. + */ +static inline void list_splice(struct list_head *list, struct list_head *head) +{ + if (!list_empty(list)) + __list_splice(list, head); +} + +/** + * list_splice_init - join two lists and reinitialise the emptied list. + * @list: the new list to add. + * @head: the place to add it in the first list. + * + * The list at @list is reinitialised + */ +static inline void list_splice_init(struct list_head *list, + struct list_head *head) +{ + if (!list_empty(list)) { + __list_splice(list, head); + INIT_LIST_HEAD(list); + } +} + +/** + * list_entry - get the struct for this entry + * @ptr: the &struct list_head pointer. + * @type: the type of the struct this is embedded in. + * @member: the name of the list_struct within the struct. + */ +#define list_entry(ptr, type, member) \ + ((type *)((char *)(ptr)-(unsigned long)(&((type *)0)->member))) + +/** + * list_for_each - iterate over a list + * @pos: the &struct list_head to use as a loop counter. + * @head: the head for your list. + */ +#define list_for_each(pos, head) \ + for (pos = (head)->next; pos != (head); \ + pos = pos->next) +/** + * list_for_each_prev - iterate over a list backwards + * @pos: the &struct list_head to use as a loop counter. + * @head: the head for your list. + */ +#define list_for_each_prev(pos, head) \ + for (pos = (head)->prev; pos != (head); \ + pos = pos->prev) + +/** + * list_for_each_safe - iterate over a list safe against removal of list entry + * @pos: the &struct list_head to use as a loop counter. + * @n: another &struct list_head to use as temporary storage + * @head: the head for your list. + */ +#define list_for_each_safe(pos, n, head) \ + for (pos = (head)->next, n = pos->next; pos != (head); \ + pos = n, n = pos->next) + +/** + * list_for_each_entry - iterate over list of given type + * @pos: the type * to use as a loop counter. + * @head: the head for your list. + * @member: the name of the list_struct within the struct. + */ +#define list_for_each_entry(pos, head, member) \ + for (pos = list_entry((head)->next, typeof(*pos), member); \ + &pos->member != (head); \ + pos = list_entry(pos->member.next, typeof(*pos), member)) + +/** + * list_for_each_entry_prev - iterate over list of given type backwards + * @pos: the type * to use as a loop counter. + * @head: the head for your list. + * @member: the name of the list_struct within the struct. + */ +#define list_for_each_entry_prev(pos, head, member) \ + for (pos = list_entry((head)->prev, typeof(*pos), member); \ + &pos->member != (head); \ + pos = list_entry(pos->member.prev, typeof(*pos), member)) + + +/** + * list_for_each_entry_safe - iterate over list of given type safe against removal of list entry + * @pos: the type * to use as a loop counter. + * @n: another type * to use as temporary storage + * @head: the head for your list. + * @member: the name of the list_struct within the struct. + */ +#define list_for_each_entry_safe(pos, n, head, member) \ + for (pos = list_entry((head)->next, typeof(*pos), member), \ + n = list_entry(pos->member.next, typeof(*pos), member); \ + &pos->member != (head); \ + pos = n, n = list_entry(n->member.next, typeof(*n), member)) + + +#endif diff --git a/modules/sparkler/particle.c b/modules/sparkler/particle.c new file mode 100644 index 0000000..0e3d2c8 --- /dev/null +++ b/modules/sparkler/particle.c @@ -0,0 +1,14 @@ +#include "particle.h" + +/* convert a particle to a new type */ +void particle_convert(particles_t *particles, particle_t *p, particle_props_t *props, particle_ops_t *ops) +{ + particle_cleanup(particles, p); + if (props) { + *p->props = *props; + } + if (ops) { + p->ops = ops; + } + particle_init(particles, p); +} diff --git a/modules/sparkler/particle.h b/modules/sparkler/particle.h new file mode 100644 index 0000000..95c117e --- /dev/null +++ b/modules/sparkler/particle.h @@ -0,0 +1,79 @@ +#ifndef _PARTICLE_H +#define _PARTICLE_H + +#include "bsp.h" +#include "fb.h" +#include "v3f.h" + +typedef struct particle_props_t { + v3f_t position; /* position in 3d space */ + v3f_t direction; /* trajectory in 3d space */ + float velocity; /* linear velocity */ + float mass; /* mass of particle */ + float drag; /* drag of particle */ + int of_use:1; /* are these properties of use/meaningful? */ +} particle_props_t; + +typedef enum particle_status_t { + PARTICLE_ALIVE, + PARTICLE_DEAD +} particle_status_t; + +typedef struct particle_t particle_t; +typedef struct particles_t particles_t; + +typedef struct particle_ops_t { + unsigned context_size; /* size of the particle context (0 for none) */ + int (*init)(particles_t *, particle_t *); /* initialize the particle, called after allocating context (optional) */ + void (*cleanup)(particles_t *, particle_t *); /* cleanup function, called before freeing context (optional) */ + particle_status_t (*sim)(particles_t *, particle_t *); /* simulate the particle for another cycle (required) */ + void (*draw)(particles_t *, particle_t *, int, int, fb_fragment_t *); /* draw the particle, 3d->2d projection has been done already (optional) */ +} particle_ops_t; + +struct particle_t { + bsp_occupant_t occupant; /* occupant node in the bsp tree */ + particle_props_t *props; + particle_ops_t *ops; + void *ctxt; +}; + + +//#define rand_within_range(_min, _max) ((rand() % (_max - _min)) + _min) +// the style of random number generator used by c libraries has less entropy in the lower bits meaning one shouldn't just use modulo, while this is slower, the results do seem a little different. +#define rand_within_range(_min, _max) (int)(((float)_min) + ((float)rand() / (float)RAND_MAX) * (_max - _min)) + +#define INHERIT_OPS NULL +#define INHERIT_PROPS NULL + + +static inline int particle_init(particles_t *particles, particle_t *p) { + if (p->ops->init) { + return p->ops->init(particles, p); + } + + return 1; +} + + +static inline void particle_cleanup(particles_t *particles, particle_t *p) { + if (p->ops->cleanup) { + p->ops->cleanup(particles, p); + } +} + + +static inline particle_status_t particle_sim(particles_t *particles, particle_t *p) { + return p->ops->sim(particles, p); +} + + +static inline void particle_draw(particles_t *particles, particle_t *p, int x, int y, fb_fragment_t *f) { + if (p->ops->draw) { + p->ops->draw(particles, p, x, y, f); + } +} + + +void particle_convert(particles_t *particles, particle_t *p, particle_props_t *props, particle_ops_t *ops); + +#endif diff --git a/modules/sparkler/particles.c b/modules/sparkler/particles.c new file mode 100644 index 0000000..ee23972 --- /dev/null +++ b/modules/sparkler/particles.c @@ -0,0 +1,338 @@ +#include <assert.h> +#include <stdio.h> +#include <stdlib.h> +#include <sys/types.h> +#include <unistd.h> +#include <math.h> +#include <stdlib.h> +#include <time.h> + +#include "fb.h" + +#include "chunker.h" +#include "container.h" +#include "bsp.h" +#include "list.h" +#include "particle.h" +#include "particles.h" +#include "v3f.h" + +#define ZCONST 0.4f + +/* private particle with all the particles bookkeeping... */ +typedef struct _particle_t { + list_head_t siblings; /* sibling particles */ + list_head_t children; /* children particles */ + + particle_props_t props; /* we reference this in the public particle, I might change + * the way props are allocated so coding everything to use a + * reference for now. It may make sense to have props allocated + * separately via their own chunker, and perform some mass operations + * against the list of chunks rather than chasing the pointers of + * the particle heirarchy. TODO + */ + particle_t public; /* the public particle_t is embedded */ + + uint8_t context[]; /* particle type-specific context [public.ops.context_size] */ +} _particle_t; + +struct particles_t { + chunker_t *chunker; /* chunker for variably-sized particle allocation (includes context) */ + list_head_t active; /* top-level active list of particles heirarchy */ + bsp_t *bsp; /* bsp spatial index of the particles */ +}; + + +/* create a new particle system */ +particles_t * particles_new(void) +{ + particles_t *particles; + + particles = calloc(1, sizeof(particles_t)); + if (!particles) { + return NULL; + } + + particles->chunker = chunker_new(sizeof(_particle_t) * 128); + if (!particles->chunker) { + return NULL; + } + + particles->bsp = bsp_new(); + if (!particles->bsp) { + return NULL; + } + + INIT_LIST_HEAD(&particles->active); + + return particles; +} + + +/* TODO: add a public interface for destroying particles? for now we just return PARTICLE_DEAD in the sim */ +static inline void _particles_free_particle(particles_t *particles, _particle_t *p) +{ + assert(p); + + particle_cleanup(particles, &p->public); + chunker_free(p); +} + + +static inline void _particles_free(particles_t *particles, list_head_t *list) +{ + _particle_t *p, *_p; + + assert(particles); + assert(list); + + list_for_each_entry_safe(p, _p, list, siblings) { + _particles_free(particles, &p->children); + _particles_free_particle(particles, p); + } +} + + +/* free up all the particles */ +void particles_free(particles_t *particles) +{ + assert(particles); + + _particles_free(particles, &particles->active); +} + + +/* reclaim a dead particle, moving it to the free list */ +static void particles_reap_particle(particles_t *particles, _particle_t *particle) +{ + assert(particles); + assert(particle); + + if (!list_empty(&particle->children)) { + /* adopt any orphaned children using the global parts list */ + list_splice(&particle->children, &particles->active); + } + + list_del(&particle->siblings); + bsp_delete_occupant(particles->bsp, &particle->public.occupant); + _particles_free_particle(particles, particle); +} + + +/* add a particle to the specified list */ +static inline int _particles_add_particle(particles_t *particles, list_head_t *list, particle_props_t *props, particle_ops_t *ops) +{ + _particle_t *p; + + assert(particles); + assert(ops); + assert(list); + + p = chunker_alloc(particles->chunker, sizeof(_particle_t) + ops->context_size); + if (!p) { + return 0; + } + + INIT_LIST_HEAD(&p->children); + INIT_LIST_HEAD(&p->siblings); + + /* inherit the parent's properties and ops if they're not explicitly provided */ + if (props) { + p->props = *props; + } else { + p->props.of_use = 0; + } + + p->public.props = &p->props; + p->public.ops = ops; + + if (ops->context_size) { + p->public.ctxt = p->context; + } + + if (!particle_init(particles, &p->public)) { + /* XXX FIXME this shouldn't be normal, we don't want to allocate + * particles that cannot be initialized. the rockets today set a cap + * by failing initialization, that's silly. */ + chunker_free(p); + return 0; + } + + p->public.props->of_use = 1; + list_add(&p->siblings, list); + bsp_add_occupant(particles->bsp, &p->public.occupant, &p->props.position); + + return 1; +} + + +/* add a new "top-level" particle of the specified props and ops taking from the provided parts list */ +int particles_add_particle(particles_t *particles, particle_props_t *props, particle_ops_t *ops) +{ + assert(particles); + + return _particles_add_particle(particles, &particles->active, props, ops); +} + + +/* spawn a new child particle from a parent, initializing it via inheritance if desired */ +void particles_spawn_particle(particles_t *particles, particle_t *parent, particle_props_t *props, particle_ops_t *ops) +{ + _particle_t *p = container_of(parent, _particle_t, public); + + assert(particles); + assert(parent); + + _particles_add_particle(particles, &p->children, props ? props : parent->props, ops ? ops : parent->ops); +} + + +/* plural version of particle_add(); adds multiple "top-level" particles of uniform props and ops */ +void particles_add_particles(particles_t *particles, particle_props_t *props, particle_ops_t *ops, int num) +{ + int i; + + assert(particles); + + for (i = 0; i < num; i++) { + _particles_add_particle(particles, &particles->active, props, ops); + } +} + + +/* Simple accessor to get the bsp pointer, the bsp is special because we don't want to do + * callbacks per-occupant, so the bsp_occupant_t and search functions are used directly by + * the per-particle code needing nearest-neighbor search. that requires an accessor since + * particles_t is opaque. This seemed less shitty than opening up particles_t. + */ +bsp_t * particles_bsp(particles_t *particles) +{ + assert(particles); + assert(particles->bsp); + + return particles->bsp; +} + + +static inline void _particles_draw(particles_t *particles, list_head_t *list, fb_fragment_t *fragment) +{ + float w2 = fragment->width / 2, h2 = fragment->height / 2; + _particle_t *p; + + assert(particles); + assert(list); + assert(fragment); + + list_for_each_entry(p, list, siblings) { + int x, y; + + /* project the 3d coordinates onto the 2d plane */ + x = ((float)(p->props.position.x / (p->props.position.z - ZCONST)) * w2) + w2; + y = ((float)(p->props.position.y / (p->props.position.z - ZCONST)) * h2) + h2; + + particle_draw(particles, &p->public, x, y, fragment); + _particles_draw(particles, &p->children, fragment); + } +} + + +/* draw all of the particles, currently called in heirarchical order */ +void particles_draw(particles_t *particles, fb_fragment_t *fragment) +{ + assert(particles); + + _particles_draw(particles, &particles->active, fragment); +} + + +static inline particle_status_t _particles_sim(particles_t *particles, list_head_t *list) +{ + particle_status_t ret = PARTICLE_DEAD, s; + _particle_t *p, *_p; + + assert(particles); + assert(list); + + list_for_each_entry_safe(p, _p, list, siblings) { + if ((s = particle_sim(particles, &p->public)) == PARTICLE_ALIVE) { + ret = PARTICLE_ALIVE; + + if (_particles_sim(particles, &p->children) == PARTICLE_ALIVE) { + ret = PARTICLE_ALIVE; + } + } else { + particles_reap_particle(particles, p); + } + } + + return ret; +} + + +/* simulate the particles, call the sim method of every particle in the heirarchy, this is what makes the particles dynamic */ +/* if any paticle is still living, we return PARTICLE_ALIVE, to inform the caller when everything's dead */ +particle_status_t particles_sim(particles_t *particles) +{ + assert(particles); + + return _particles_sim(particles, &particles->active); +} + + +static inline void _particles_age(particles_t *particles, list_head_t *list) +{ + _particle_t *p; + + assert(particles); + assert(list); + + /* TODO: since this *only* involves the properties struct, if they were + * allocated from a separate slab containing only properties, it'd be + * more efficient to iterate across property arrays and skip inactive + * entries. This heirarchical pointer-chasing recursion isn't + * particularly good for cache utilization. + */ + list_for_each_entry(p, list, siblings) { +#if 1 + if (p->props.mass > 0.0f) { + /* gravity, TODO: mass isn't applied. */ + static v3f_t gravity = v3f_init(0.0f, -1.0f, 0.0f); + v3f_t g; + + g = v3f_mult_scalar(&gravity, 0.08f); + p->props.direction = v3f_add(&p->props.direction, &g); + p->props.direction = v3f_normalize(&p->props.direction); + } +#endif + +#if 1 + /* some drag/resistance proportional to velocity TODO: integrate mass */ + if (p->props.velocity > 0.0f) { + p->props.velocity -= ((p->props.velocity * p->props.velocity * p->props.drag)); + if (p->props.velocity < 0.0f) { + p->props.velocity = 0; + } + } +#endif + + /* regular movement */ + if (p->props.velocity > 0.0f) { + v3f_t movement = v3f_mult_scalar(&p->props.direction, p->props.velocity); + + p->props.position = v3f_add(&p->props.position, &movement); + bsp_move_occupant(particles->bsp, &p->public.occupant, &p->props.position); + } + + _particles_age(particles, &p->children); + } +} + + +/* advance time for all the particles (move them), this doesn't currently invoke any part-specific helpers, it's just applying + * physics-type stuff, moving particles according to their velocities, directions, mass, drag, gravity etc... */ +void particles_age(particles_t *particles) +{ + assert(particles); + + _particles_age(particles, &particles->active); +} diff --git a/modules/sparkler/particles.h b/modules/sparkler/particles.h new file mode 100644 index 0000000..689934b --- /dev/null +++ b/modules/sparkler/particles.h @@ -0,0 +1,21 @@ +#ifndef _PARTICLES_H +#define _PARTICLES_H + +#include "bsp.h" +#include "fb.h" +#include "list.h" +#include "particle.h" + +typedef struct particles_t particles_t; + +particles_t * particles_new(void); +void particles_draw(particles_t *particles, fb_fragment_t *fragment); +particle_status_t particles_sim(particles_t *particles); +void particles_age(particles_t *particles); +void particles_free(particles_t *particles); +int particles_add_particle(particles_t *particles, particle_props_t *props, particle_ops_t *ops); +void particles_spawn_particle(particles_t *particles, particle_t *parent, particle_props_t *props, particle_ops_t *ops); +void particles_add_particles(particles_t *particles, particle_props_t *props, particle_ops_t *ops, int num); +bsp_t * particles_bsp(particles_t *particles); + +#endif diff --git a/modules/sparkler/rocket.c b/modules/sparkler/rocket.c new file mode 100644 index 0000000..6b9dc5e --- /dev/null +++ b/modules/sparkler/rocket.c @@ -0,0 +1,144 @@ +#include <stdlib.h> + +#include "draw.h" +#include "particle.h" +#include "particles.h" + +/* a "rocket" particle type */ +#define ROCKET_MAX_DECAY_RATE 20 +#define ROCKET_MIN_DECAY_RATE 2 +#define ROCKET_MAX_LIFETIME 500 +#define ROCKET_MIN_LIFETIME 300 +#define ROCKETS_MAX 20 +#define ROCKETS_XPLODE_MIN_SIZE 2000 +#define ROCKETS_XPLODE_MAX_SIZE 8000 + +extern particle_ops_t burst_ops; +extern particle_ops_t spark_ops; +extern particle_ops_t xplode_ops; + +static unsigned rockets_cnt; + +typedef struct rocket_ctxt_t { + int decay_rate; + int longevity; + v3f_t wander; + float last_velocity; /* cache velocity to sense violent accelerations and explode when they happen */ +} rocket_ctxt_t; + + +static int rocket_init(particles_t *particles, particle_t *p) +{ + rocket_ctxt_t *ctxt = p->ctxt; + + if (rockets_cnt >= ROCKETS_MAX) { + return 0; + } + rockets_cnt++; + + ctxt->decay_rate = rand_within_range(ROCKET_MIN_DECAY_RATE, ROCKET_MAX_DECAY_RATE); + ctxt->longevity = rand_within_range(ROCKET_MIN_LIFETIME, ROCKET_MAX_LIFETIME); + + ctxt->wander.x = (float)(rand_within_range(0, 628) - 314) / 10000.0f; + ctxt->wander.y = (float)(rand_within_range(0, 628) - 314) / 10000.0f; + ctxt->wander.z = (float)(rand_within_range(0, 628) - 314) / 10000.0f; + ctxt->wander = v3f_normalize(&ctxt->wander); + + ctxt->last_velocity = p->props->velocity; + p->props->drag = 0.4; + p->props->mass = 0.8; + + return 1; +} + + +static particle_status_t rocket_sim(particles_t *particles, particle_t *p) +{ + rocket_ctxt_t *ctxt = p->ctxt; + int i, n_sparks; + + if (!ctxt->longevity || + (ctxt->longevity -= ctxt->decay_rate) <= 0 || + p->props->velocity - ctxt->last_velocity > p->props->velocity * .05) { /* explode if accelerated too hard (burst) */ + int n_xplode; + /* on death we explode */ + + ctxt->longevity = 0; + + /* add a burst shockwave particle at our location + * TODO: need way to supply particle-type-specific parameters at spawn (burst size should derive from n_xplode) + */ + particles_spawn_particle(particles, p, NULL, &burst_ops); + + /* add a bunch of new explosion particles */ + /* TODO: also particle-type-specific parameters, colors! rocket bursts should be able to vary the color. */ + n_xplode = rand_within_range(ROCKETS_XPLODE_MIN_SIZE, ROCKETS_XPLODE_MAX_SIZE); + for (i = 0; i < n_xplode; i++) { + particle_props_t props = *p->props; + particle_ops_t *ops = &xplode_ops; + + props.direction.x = ((float)(rand_within_range(0, 314159 * 2) - 314159) / 100000.0); + props.direction.y = ((float)(rand_within_range(0, 314159 * 2) - 314159) / 100000.0); + props.direction.z = ((float)(rand_within_range(0, 314159 * 2) - 314159) / 100000.0); + props.direction = v3f_normalize(&props.direction); + + //props->velocity = ((float)rand_within_range(100, 200) / 100000.0); + props.velocity = ((float)rand_within_range(100, 300) / 100000.0); + particles_spawn_particle(particles, p, &props, ops); + } + return PARTICLE_DEAD; + } + +#if 1 + /* FIXME: this isn't behaving as intended */ + p->props->direction = v3f_add(&p->props->direction, &ctxt->wander); + p->props->direction = v3f_normalize(&p->props->direction); +#endif + p->props->velocity += .00003; + + /* spray some sparks behind the rocket */ + n_sparks = rand_within_range(10, 40); + for (i = 0; i < n_sparks; i++) { + particle_props_t props = *p->props; + + props.direction = v3f_negate(&props.direction); + + props.direction.x += (float)(rand_within_range(0, 40) - 20) / 100.0; + props.direction.y += (float)(rand_within_range(0, 40) - 20) / 100.0; + props.direction.z += (float)(rand_within_range(0, 40) - 20) / 100.0; + props.direction = v3f_normalize(&props.direction); + + props.velocity = (float)rand_within_range(10, 50) / 100000.0; + particles_spawn_particle(particles, p, &props, &spark_ops); + } + + ctxt->last_velocity = p->props->velocity; + + return PARTICLE_ALIVE; +} + + +static void rocket_draw(particles_t *particles, particle_t *p, int x, int y, fb_fragment_t *f) +{ + rocket_ctxt_t *ctxt = p->ctxt; + + if (!draw_pixel(f, x, y, 0xff0000)) { + /* kill off parts that wander off screen */ + ctxt->longevity = 0; + } +} + + +static void rocket_cleanup(particles_t *particles, particle_t *p) +{ + rockets_cnt--; +} + + +particle_ops_t rocket_ops = { + .context_size = sizeof(rocket_ctxt_t), + .sim = rocket_sim, + .init = rocket_init, + .draw = rocket_draw, + .cleanup = rocket_cleanup, + }; diff --git a/modules/sparkler/simple.c b/modules/sparkler/simple.c new file mode 100644 index 0000000..e453e46 --- /dev/null +++ b/modules/sparkler/simple.c @@ -0,0 +1,113 @@ +#include <stdlib.h> + +#include "draw.h" +#include "particle.h" +#include "particles.h" + + +/* a "simple" particle type */ +#define SIMPLE_MAX_DECAY_RATE 20 +#define SIMPLE_MIN_DECAY_RATE 2 +#define SIMPLE_MAX_LIFETIME 110 +#define SIMPLE_MIN_LIFETIME 30 +#define SIMPLE_MAX_SPAWN 15 +#define SIMPLE_MIN_SPAWN 2 + +extern particle_ops_t rocket_ops; + +typedef struct _simple_ctxt_t { + int decay_rate; + int longevity; + int lifetime; +} simple_ctxt_t; + + +static int simple_init(particles_t *particles, particle_t *p) +{ + simple_ctxt_t *ctxt = p->ctxt; + + ctxt->decay_rate = rand_within_range(SIMPLE_MIN_DECAY_RATE, SIMPLE_MAX_DECAY_RATE); + ctxt->lifetime = ctxt->longevity = rand_within_range(SIMPLE_MIN_LIFETIME, SIMPLE_MAX_LIFETIME); + + if (!p->props->of_use) { + /* everything starts from the bottom center */ + p->props->position.x = 0; + p->props->position.y = 0; + p->props->position.z = 0; + + /* TODO: direction random-ish within the range of a narrow upward facing cone */ + p->props->direction.x = (float)(rand_within_range(0, 6) - 3) * .1f; + p->props->direction.y = 1.0f + (float)(rand_within_range(0, 6) - 3) * .1f; + p->props->direction.z = (float)(rand_within_range(0, 6) - 3) * .1f; + p->props->direction = v3f_normalize(&p->props->direction); + + p->props->velocity = (float)rand_within_range(300, 800) / 100000.0; + + p->props->drag = 0.03; + p->props->mass = 0.3; + p->props->of_use = 1; + } /* else { we've been given properties, manipulate them or run with them? } */ + + return 1; +} + + +static particle_status_t simple_sim(particles_t *particles, particle_t *p) +{ + simple_ctxt_t *ctxt = p->ctxt; + + /* a particle is free to manipulate its children list when aging, but not itself or its siblings */ + /* return PARTICLE_DEAD to remove kill yourself, do not age children here, the age pass will recurse + * into children and age them independently _after_ their parents have been aged + */ + if (!ctxt->longevity || (ctxt->longevity -= ctxt->decay_rate) <= 0) { + ctxt->longevity = 0; + return PARTICLE_DEAD; + } + + /* create particles inheriting our type based on some silly conditions, with some tweaks to their direction */ + if (ctxt->longevity == 42 || (ctxt->longevity > 500 && !(ctxt->longevity % 50))) { + int i, num = rand_within_range(SIMPLE_MIN_SPAWN, SIMPLE_MAX_SPAWN); + + for (i = 0; i < num; i++) { + particle_props_t props = *p->props; + particle_ops_t *ops = INHERIT_OPS; + + if (i == (SIMPLE_MAX_SPAWN - 2)) { + ops = &rocket_ops; + props.velocity = (float)rand_within_range(60, 100) / 1000000.0; + } else { + props.velocity = (float)rand_within_range(30, 100) / 10000.0; + } + + props.direction.x += (float)(rand_within_range(0, 315 * 2) - 315) / 100.0; + props.direction.y += (float)(rand_within_range(0, 315 * 2) - 315) / 100.0; + props.direction.z += (float)(rand_within_range(0, 315 * 2) - 315) / 100.0; + props.direction = v3f_normalize(&props.direction); + + particles_spawn_particle(particles, p, &props, ops); // XXX + } + } + + return PARTICLE_ALIVE; +} + + +static void simple_draw(particles_t *particles, particle_t *p, int x, int y, fb_fragment_t *f) +{ + simple_ctxt_t *ctxt = p->ctxt; + + if (!draw_pixel(f, x, y, makergb(0xff, 0xff, 0xff, ((float)ctxt->longevity / ctxt->lifetime)))) { + /* immediately kill off stars that wander off screen */ + ctxt->longevity = 0; + } +} + + +particle_ops_t simple_ops = { + .context_size = sizeof(simple_ctxt_t), + .sim = simple_sim, + .init = simple_init, + .draw = simple_draw, + .cleanup = NULL, + }; diff --git a/modules/sparkler/spark.c b/modules/sparkler/spark.c new file mode 100644 index 0000000..ea68ac2 --- /dev/null +++ b/modules/sparkler/spark.c @@ -0,0 +1,63 @@ +#include <stdlib.h> + +#include "draw.h" +#include "particle.h" +#include "particles.h" + +/* a "spark" particle type, emitted from behind rockets */ +#define SPARK_MAX_DECAY_RATE 20 +#define SPARK_MIN_DECAY_RATE 2 +#define SPARK_MAX_LIFETIME 150 +#define SPARK_MIN_LIFETIME 1 + +typedef struct _spark_ctxt_t { + int decay_rate; + int longevity; + int lifetime; +} spark_ctxt_t; + + +static int spark_init(particles_t *particles, particle_t *p) +{ + spark_ctxt_t *ctxt = p->ctxt; + + p->props->drag = 20.0; + p->props->mass = 0.1; + ctxt->decay_rate = rand_within_range(SPARK_MIN_DECAY_RATE, SPARK_MAX_DECAY_RATE); + ctxt->lifetime = ctxt->longevity = rand_within_range(SPARK_MIN_LIFETIME, SPARK_MAX_LIFETIME); + + return 1; +} + + +static particle_status_t spark_sim(particles_t *particles, particle_t *p) +{ + spark_ctxt_t *ctxt = p->ctxt; + + if (!ctxt->longevity || (ctxt->longevity -= ctxt->decay_rate) <= 0) { + ctxt->longevity = 0; + return PARTICLE_DEAD; + } + + return PARTICLE_ALIVE; +} + + +static void spark_draw(particles_t *particles, particle_t *p, int x, int y, fb_fragment_t *f) +{ + spark_ctxt_t *ctxt = p->ctxt; + + if (!draw_pixel(f, x, y, makergb(0xff, 0xa0, 0x20, ((float)ctxt->longevity / ctxt->lifetime)))) { + /* offscreen */ + ctxt->longevity = 0; + } +} + + +particle_ops_t spark_ops = { + .context_size = sizeof(spark_ctxt_t), + .sim = spark_sim, + .init = spark_init, + .draw = spark_draw, + .cleanup = NULL, + }; diff --git a/modules/sparkler/sparkler.c b/modules/sparkler/sparkler.c new file mode 100644 index 0000000..de2123e --- /dev/null +++ b/modules/sparkler/sparkler.c @@ -0,0 +1,53 @@ +#include <stdlib.h> +#include <string.h> +#include <sys/types.h> +#include <time.h> +#include <unistd.h> + +#include "fb.h" +#include "rototiller.h" +#include "util.h" + +#include "particles.h" + +/* particle system gadget (C) Vito Caputo <vcaputo@pengaru.com> 2/15/2014 */ +/* 1/10/2015 added octree bsp (though not yet leveraged) */ +/* 11/25/2016 refactor and begun adapting to rototiller */ + +#define INIT_PARTS 100 + +extern particle_ops_t simple_ops; + + +/* Render a 3D particle system */ +static void sparkler(fb_fragment_t *fragment) +{ + static particles_t *particles; + static int initialized; + uint32_t *buf = fragment->buf; + + if (!initialized) { + srand(time(NULL) + getpid()); + + particles = particles_new(); + particles_add_particles(particles, NULL, &simple_ops, INIT_PARTS); + + initialized = 1; + } + + particles_age(particles); + memset(buf, 0, ((fragment->width << 2) + fragment->stride) * fragment->height); + + particles_draw(particles, fragment); + particles_sim(particles); + particles_add_particles(particles, NULL, &simple_ops, INIT_PARTS / 4); +} + + +rototiller_renderer_t sparkler_renderer = { + .render = sparkler, + .name = "sparkler", + .description = "Particle system with spatial interactions", + .author = "Vito Caputo <vcaputo@pengaru.com>", + .license = "GPLv2", +}; diff --git a/modules/sparkler/sparkler.h b/modules/sparkler/sparkler.h new file mode 100644 index 0000000..3beb610 --- /dev/null +++ b/modules/sparkler/sparkler.h @@ -0,0 +1,8 @@ +#ifndef _SPARKLER_H +#define _SPARKLER_H + +#include "fb.h" + +void sparkler(fb_fragment_t *fragment); + +#endif diff --git a/modules/sparkler/v3f.h b/modules/sparkler/v3f.h new file mode 100644 index 0000000..8bf7e24 --- /dev/null +++ b/modules/sparkler/v3f.h @@ -0,0 +1,157 @@ +#ifndef _V3F_H +#define _V3F_H + +#include <math.h> + +typedef struct v3f_t { + float x, y, z; +} v3f_t; + +#define v3f_set(_v3f, _x, _y, _z) \ + (_v3f)->x = _x; \ + (_v3f)->y = _y; \ + (_v3f)->z = _z; + +#define v3f_init(_x, _y, _z) \ + { \ + .x = _x, \ + .y = _y, \ + .z = _z, \ + } + +/* return if a and b are equal */ +static inline int v3f_equal(v3f_t *a, v3f_t *b) +{ + return (a->x == b->x && a->y == b->y && a->z == b->z); +} + + +/* return the result of (a + b) */ +static inline v3f_t v3f_add(v3f_t *a, v3f_t *b) +{ + v3f_t res = v3f_init(a->x + b->x, a->y + b->y, a->z + b->z); + + return res; +} + + +/* return the result of (a - b) */ +static inline v3f_t v3f_sub(v3f_t *a, v3f_t *b) +{ + v3f_t res = v3f_init(a->x - b->x, a->y - b->y, a->z - b->z); + + return res; +} + + +/* return the result of (-v) */ +static inline v3f_t v3f_negate(v3f_t *v) +{ + v3f_t res = v3f_init(-v->x, -v->y, -v->z); + + return res; +} + + +/* return the result of (a * b) */ +static inline v3f_t v3f_mult(v3f_t *a, v3f_t *b) +{ + v3f_t res = v3f_init(a->x * b->x, a->y * b->y, a->z * b->z); + + return res; +} + + +/* return the result of (v * scalar) */ +static inline v3f_t v3f_mult_scalar(v3f_t *v, float scalar) +{ + v3f_t res = v3f_init( v->x * scalar, v->y * scalar, v->z * scalar); + + return res; +} + + +/* return the result of (uv / scalar) */ +static inline v3f_t v3f_div_scalar(v3f_t *v, float scalar) +{ + v3f_t res = v3f_init(v->x / scalar, v->y / scalar, v->z / scalar); + + return res; +} + + +/* return the result of (a . b) */ +static inline float v3f_dot(v3f_t *a, v3f_t *b) +{ + return a->x * b->x + a->y * b->y + a->z * b->z; +} + + +/* return the length of the supplied vector */ +static inline float v3f_length(v3f_t *v) +{ + return sqrtf(v3f_dot(v, v)); +} + + +/* return the normalized form of the supplied vector */ +static inline v3f_t v3f_normalize(v3f_t *v) +{ + v3f_t nv; + float f; + + f = 1.0f / v3f_length(v); + + v3f_set(&nv, f * v->x, f * v->y, f * v->z); + + return nv; +} + + +/* return the distance squared between two arbitrary points */ +static inline float v3f_distance_sq(v3f_t *a, v3f_t *b) +{ + return powf(a->x - b->x, 2) + powf(a->y - b->y, 2) + powf(a->z - b->z, 2); +} + + +/* return the distance between two arbitrary points */ +/* (consider using v3f_distance_sq() instead if possible, sqrtf() is slow) */ +static inline float v3f_distance(v3f_t *a, v3f_t *b) +{ + return sqrtf(v3f_distance_sq(a, b)); +} + + +/* return the cross product of two unit vectors */ +static inline v3f_t v3f_cross(v3f_t *a, v3f_t *b) +{ + v3f_t product = v3f_init(a->y * b->z - a->z * b->y, a->z * b->x - a->x * b->z, a->x * b->y - a->y * b->x); + + return product; +} + + +/* return the linearly interpolated vector between the two vectors at point alpha (0-1.0) */ +static inline v3f_t v3f_lerp(v3f_t *a, v3f_t *b, float alpha) +{ + v3f_t lerp_a, lerp_b; + + lerp_a = v3f_mult_scalar(a, 1.0f - alpha); + lerp_b = v3f_mult_scalar(b, alpha); + + return v3f_add(&lerp_a, &lerp_b); +} + + +/* return the normalized linearly interpolated vector between the two vectors at point alpha (0-1.0) */ +static inline v3f_t v3f_nlerp(v3f_t *a, v3f_t *b, float alpha) +{ + v3f_t lerp; + + lerp = v3f_lerp(a, b, alpha); + + return v3f_normalize(&lerp); +} + +#endif diff --git a/modules/sparkler/xplode.c b/modules/sparkler/xplode.c new file mode 100644 index 0000000..24a436e --- /dev/null +++ b/modules/sparkler/xplode.c @@ -0,0 +1,82 @@ +#include <stdlib.h> + +#include "draw.h" +#include "particle.h" +#include "particles.h" + +/* a "xplode" particle type, emitted by rockets in large numbers at the end of their lifetime */ +#define XPLODE_MAX_DECAY_RATE 10 +#define XPLODE_MIN_DECAY_RATE 5 +#define XPLODE_MAX_LIFETIME 150 +#define XPLODE_MIN_LIFETIME 5 + +extern particle_ops_t spark_ops; +particle_ops_t xplode_ops; + +typedef struct _xplode_ctxt_t { + int decay_rate; + int longevity; + int lifetime; +} xplode_ctxt_t; + + +static int xplode_init(particles_t *particles, particle_t *p) +{ + xplode_ctxt_t *ctxt = p->ctxt; + + ctxt->decay_rate = rand_within_range(XPLODE_MIN_DECAY_RATE, XPLODE_MAX_DECAY_RATE); + ctxt->lifetime = ctxt->longevity = rand_within_range(XPLODE_MIN_LIFETIME, XPLODE_MAX_LIFETIME); + + p->props->drag = 10.9; + p->props->mass = 0.3; + + return 1; +} + + +static particle_status_t xplode_sim(particles_t *particles, particle_t *p) +{ + xplode_ctxt_t *ctxt = p->ctxt; + + if (!ctxt->longevity || (ctxt->longevity -= ctxt->decay_rate) <= 0) { + ctxt->longevity = 0; + return PARTICLE_DEAD; + } + + /* litter some small sparks behind the explosion particle */ + if (!(ctxt->lifetime % 30)) { + particle_props_t props = *p->props; + + props.velocity = (float)rand_within_range(10, 50) / 10000.0; + particles_spawn_particle(particles, p, &props, &xplode_ops); + } + + return PARTICLE_ALIVE; +} + + +static void xplode_draw(particles_t *particles, particle_t *p, int x, int y, fb_fragment_t *f) +{ + xplode_ctxt_t *ctxt = p->ctxt; + uint32_t color; + + if (ctxt->longevity == ctxt->lifetime) { + color = makergb(0xff, 0xff, 0xa0, 1.0); + } else { + color = makergb(0xff, 0xff, 0x00, ((float)ctxt->longevity / ctxt->lifetime)); + } + + if (!draw_pixel(f, x, y, color)) { + /* offscreen */ + ctxt->longevity = 0; + } +} + + +particle_ops_t xplode_ops = { + .context_size = sizeof(xplode_ctxt_t), + .sim = xplode_sim, + .init = xplode_init, + .draw = xplode_draw, + .cleanup = NULL, + }; |