From 524db0cf19648e3c7c78d3e73103b7a0bdcd6bfc Mon Sep 17 00:00:00 2001 From: Vito Caputo Date: Wed, 18 Jan 2017 17:14:52 -0800 Subject: *: move source into src/ subdir Restoring some organizational sanity since adopting autotools. --- src/modules/ray/Makefile.am | 4 + src/modules/ray/ray.c | 161 ++++++++++++++++++++++++++++++ src/modules/ray/ray.h | 8 ++ src/modules/ray/ray_3f.h | 161 ++++++++++++++++++++++++++++++ src/modules/ray/ray_camera.c | 85 ++++++++++++++++ src/modules/ray/ray_camera.h | 77 +++++++++++++++ src/modules/ray/ray_color.h | 29 ++++++ src/modules/ray/ray_euler.h | 45 +++++++++ src/modules/ray/ray_light_emitter.h | 18 ++++ src/modules/ray/ray_object.c | 74 ++++++++++++++ src/modules/ray/ray_object.h | 24 +++++ src/modules/ray/ray_object_light.h | 67 +++++++++++++ src/modules/ray/ray_object_plane.h | 46 +++++++++ src/modules/ray/ray_object_point.h | 37 +++++++ src/modules/ray/ray_object_sphere.h | 65 +++++++++++++ src/modules/ray/ray_object_type.h | 11 +++ src/modules/ray/ray_ray.h | 11 +++ src/modules/ray/ray_scene.c | 188 ++++++++++++++++++++++++++++++++++++ src/modules/ray/ray_scene.h | 27 ++++++ src/modules/ray/ray_surface.h | 14 +++ src/modules/ray/ray_threads.c | 111 +++++++++++++++++++++ src/modules/ray/ray_threads.h | 30 ++++++ 22 files changed, 1293 insertions(+) create mode 100644 src/modules/ray/Makefile.am create mode 100644 src/modules/ray/ray.c create mode 100644 src/modules/ray/ray.h create mode 100644 src/modules/ray/ray_3f.h create mode 100644 src/modules/ray/ray_camera.c create mode 100644 src/modules/ray/ray_camera.h create mode 100644 src/modules/ray/ray_color.h create mode 100644 src/modules/ray/ray_euler.h create mode 100644 src/modules/ray/ray_light_emitter.h create mode 100644 src/modules/ray/ray_object.c create mode 100644 src/modules/ray/ray_object.h create mode 100644 src/modules/ray/ray_object_light.h create mode 100644 src/modules/ray/ray_object_plane.h create mode 100644 src/modules/ray/ray_object_point.h create mode 100644 src/modules/ray/ray_object_sphere.h create mode 100644 src/modules/ray/ray_object_type.h create mode 100644 src/modules/ray/ray_ray.h create mode 100644 src/modules/ray/ray_scene.c create mode 100644 src/modules/ray/ray_scene.h create mode 100644 src/modules/ray/ray_surface.h create mode 100644 src/modules/ray/ray_threads.c create mode 100644 src/modules/ray/ray_threads.h (limited to 'src/modules/ray') diff --git a/src/modules/ray/Makefile.am b/src/modules/ray/Makefile.am new file mode 100644 index 0000000..a0b3fbb --- /dev/null +++ b/src/modules/ray/Makefile.am @@ -0,0 +1,4 @@ +noinst_LIBRARIES = libray.a +libray_a_SOURCES = ray_3f.h ray.c ray_camera.c ray_camera.h ray_color.h ray_euler.h ray.h ray_light_emitter.h ray_object.c ray_object.h ray_object_light.h ray_object_plane.h ray_object_point.h ray_object_sphere.h ray_object_type.h ray_ray.h ray_scene.c ray_scene.h ray_surface.h ray_threads.c ray_threads.h +libray_a_CFLAGS = @ROTOTILLER_CFLAGS@ -ffast-math +libray_a_CPPFLAGS = @ROTOTILLER_CFLAGS@ -I../../ diff --git a/src/modules/ray/ray.c b/src/modules/ray/ray.c new file mode 100644 index 0000000..60d08cf --- /dev/null +++ b/src/modules/ray/ray.c @@ -0,0 +1,161 @@ +#include +#include +#include + +#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 */ + +/* 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 ", + .license = "GPLv2", +}; diff --git a/src/modules/ray/ray.h b/src/modules/ray/ray.h new file mode 100644 index 0000000..d33f96a --- /dev/null +++ b/src/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/src/modules/ray/ray_3f.h b/src/modules/ray/ray_3f.h new file mode 100644 index 0000000..8408abb --- /dev/null +++ b/src/modules/ray/ray_3f.h @@ -0,0 +1,161 @@ +#ifndef _RAY_3F_H +#define _RAY_3F_H + +#include + +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/src/modules/ray/ray_camera.c b/src/modules/ray/ray_camera.c new file mode 100644 index 0000000..0703c2e --- /dev/null +++ b/src/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/src/modules/ray/ray_camera.h b/src/modules/ray/ray_camera.h new file mode 100644 index 0000000..387f8c5 --- /dev/null +++ b/src/modules/ray/ray_camera.h @@ -0,0 +1,77 @@ +#ifndef _RAY_CAMERA_H +#define _RAY_CAMERA_H + +#include + +#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/src/modules/ray/ray_color.h b/src/modules/ray/ray_color.h new file mode 100644 index 0000000..9fe62c1 --- /dev/null +++ b/src/modules/ray/ray_color.h @@ -0,0 +1,29 @@ +#ifndef _RAY_COLOR_H +#define _RAY_COLOR_H + +#include + +#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/src/modules/ray/ray_euler.h b/src/modules/ray/ray_euler.h new file mode 100644 index 0000000..86f5221 --- /dev/null +++ b/src/modules/ray/ray_euler.h @@ -0,0 +1,45 @@ +#ifndef _RAY_EULER_H +#define _RAY_EULER_H + +#include + +#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/src/modules/ray/ray_light_emitter.h b/src/modules/ray/ray_light_emitter.h new file mode 100644 index 0000000..3b5509e --- /dev/null +++ b/src/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/src/modules/ray/ray_object.c b/src/modules/ray/ray_object.c new file mode 100644 index 0000000..4c5ccaf --- /dev/null +++ b/src/modules/ray/ray_object.c @@ -0,0 +1,74 @@ +#include + +#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_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); + default: + assert(0); + } +} + + +/* 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); + default: + assert(0); + } +} + + +/* 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); + default: + assert(0); + } +} diff --git a/src/modules/ray/ray_object.h b/src/modules/ray/ray_object.h new file mode 100644 index 0000000..abdb254 --- /dev/null +++ b/src/modules/ray/ray_object.h @@ -0,0 +1,24 @@ +#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_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/src/modules/ray/ray_object_light.h b/src/modules/ray/ray_object_light.h new file mode 100644 index 0000000..342c050 --- /dev/null +++ b/src/modules/ray/ray_object_light.h @@ -0,0 +1,67 @@ +#ifndef _RAY_OBJECT_LIGHT_H +#define _RAY_OBJECT_LIGHT_H + +#include + +#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_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); + default: + assert(0); + } +} + + +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; + default: + assert(0); + } +} + + +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); + default: + assert(0); + } +} + +#endif diff --git a/src/modules/ray/ray_object_plane.h b/src/modules/ray/ray_object_plane.h new file mode 100644 index 0000000..b33f342 --- /dev/null +++ b/src/modules/ray/ray_object_plane.h @@ -0,0 +1,46 @@ +#ifndef _RAY_OBJECT_PLANE_H +#define _RAY_OBJECT_PLANE_H + +#include "ray_object_type.h" +#include "ray_ray.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/src/modules/ray/ray_object_point.h b/src/modules/ray/ray_object_point.h new file mode 100644 index 0000000..c0c9610 --- /dev/null +++ b/src/modules/ray/ray_object_point.h @@ -0,0 +1,37 @@ +#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_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/src/modules/ray/ray_object_sphere.h b/src/modules/ray/ray_object_sphere.h new file mode 100644 index 0000000..85b3d93 --- /dev/null +++ b/src/modules/ray/ray_object_sphere.h @@ -0,0 +1,65 @@ +#ifndef _RAY_OBJECT_SPHERE_H +#define _RAY_OBJECT_SPHERE_H + +#include +#include + +#include "ray_3f.h" +#include "ray_color.h" +#include "ray_object_type.h" +#include "ray_ray.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/src/modules/ray/ray_object_type.h b/src/modules/ray/ray_object_type.h new file mode 100644 index 0000000..6ce20f5 --- /dev/null +++ b/src/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/src/modules/ray/ray_ray.h b/src/modules/ray/ray_ray.h new file mode 100644 index 0000000..91469a2 --- /dev/null +++ b/src/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/src/modules/ray/ray_scene.c b/src/modules/ray/ray_scene.c new file mode 100644 index 0000000..e44990b --- /dev/null +++ b/src/modules/ray/ray_scene.c @@ -0,0 +1,188 @@ +#include +#include + +#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/src/modules/ray/ray_scene.h b/src/modules/ray/ray_scene.h new file mode 100644 index 0000000..e9781c6 --- /dev/null +++ b/src/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/src/modules/ray/ray_surface.h b/src/modules/ray/ray_surface.h new file mode 100644 index 0000000..b3e3c68 --- /dev/null +++ b/src/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/src/modules/ray/ray_threads.c b/src/modules/ray/ray_threads.c new file mode 100644 index 0000000..2369687 --- /dev/null +++ b/src/modules/ray/ray_threads.c @@ -0,0 +1,111 @@ +#include +#include + +#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/src/modules/ray/ray_threads.h b/src/modules/ray/ray_threads.h new file mode 100644 index 0000000..b4c601d --- /dev/null +++ b/src/modules/ray/ray_threads.h @@ -0,0 +1,30 @@ +#ifndef _RAY_THREADS_H +#define _RAY_THREADS_H + +#include + +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 -- cgit v1.2.3