4 files changed, 15 insertions, 18 deletions
diff --git a/src/modules/ray/ray.c b/src/modules/ray/ray.c
index 89d114c..ac00806 100644
--- a/src/modules/ray/ray.c
+++ b/src/modules/ray/ray.c
@@ -98,7 +98,7 @@ static ray_camera_t	camera = {
 					.order = RAY_EULER_ORDER_YPR, /* yaw,pitch,roll */
 					.yaw = RAY_EULER_DEGREES(0.0f),
 					.pitch = RAY_EULER_DEGREES(0.0f),
-					.roll = RAY_EULER_DEGREES(180.0f),
+					.roll = RAY_EULER_DEGREES(0.0f),
 				},
 				.focal_length = 700.0f,
 			};
@@ -128,7 +128,7 @@ static void ray_prepare_frame(void *context, unsigned n_cpus, fb_fragment_t *fra
 #if 1
 	/* animated point light source */
 
-	r += .02;
+	r += -.02;
 
 	scene.lights[0].light.emitter.point.center.x = cosf(r) * 4.5f;
 	scene.lights[0].light.emitter.point.center.z = sinf(r * 3.0f) * 4.5f;
@@ -141,10 +141,11 @@ static void ray_prepare_frame(void *context, unsigned n_cpus, fb_fragment_t *fra
 	camera.position.y = cosf(r * 1.3f) * 4.0f + 2.08f;
 
 	/* keep camera facing the origin */
-	camera.orientation.yaw = r;
+	camera.orientation.yaw = r + RAY_EULER_DEGREES(180.0f);
+
 
 	/* tilt camera pitch in time with up and down movements, phase shifted appreciably */
-	camera.orientation.pitch = sinf((M_PI * 1.5f) + r * 1.3f) * .6f + -.35f;
+	camera.orientation.pitch = -(sinf((M_PI * 1.5f) + r * 1.3f) * .6f + -.35f);
 #endif
 	ray_scene_prepare(&scene, &camera);
 }
diff --git a/src/modules/ray/ray_object_plane.h b/src/modules/ray/ray_object_plane.h
index 490238c..0d3a51b 100644
--- a/src/modules/ray/ray_object_plane.h
+++ b/src/modules/ray/ray_object_plane.h
@@ -29,14 +29,14 @@ static inline int ray_object_plane_intersects_ray(ray_object_plane_t *plane, uns
 {
 	float	d = ray_3f_dot(&plane->normal, &ray->direction);
 
-	if (d >= 0.00001f) {
+	if (d < 0.0f) {
 		float	distance = plane->_prepared.primary_dot_plus;
 
 		if (depth)
 			distance = (ray_3f_dot(&plane->normal, &ray->origin) + plane->distance);
 
-		distance /= d;
-		if (distance > 0) {
+		distance /= -d;
+		if (distance > 0.0f) {
 			*res_distance = distance;
 
 			return 1;
diff --git a/src/modules/ray/ray_object_sphere.h b/src/modules/ray/ray_object_sphere.h
index c07f345..0077a68 100644
--- a/src/modules/ray/ray_object_sphere.h
+++ b/src/modules/ray/ray_object_sphere.h
@@ -27,7 +27,7 @@ typedef struct ray_object_sphere_t {
 
 static void ray_object_sphere_prepare(ray_object_sphere_t *sphere, ray_camera_t *camera)
 {
-	sphere->_prepared.primary_v = ray_3f_sub(&camera->position, &sphere->center);
+	sphere->_prepared.primary_v = ray_3f_sub(&sphere->center, &camera->position);
 	sphere->_prepared.primary_dot_vv = ray_3f_dot(&sphere->_prepared.primary_v, &sphere->_prepared.primary_v);
 
 	sphere->_prepared.r2 = sphere->radius * sphere->radius;
@@ -44,7 +44,7 @@ static inline int ray_object_sphere_intersects_ray(ray_object_sphere_t *sphere,
 	float		b, disc;
 
 	if (depth) {
-		v = ray_3f_sub(&ray->origin, &sphere->center);
+		v = ray_3f_sub(&sphere->center, &ray->origin);
 		dot_vv = ray_3f_dot(&v, &v);
 	}
 
diff --git a/src/modules/ray/ray_scene.c b/src/modules/ray/ray_scene.c
index 2ad7f99..2026f6d 100644
--- a/src/modules/ray/ray_scene.c
+++ b/src/modules/ray/ray_scene.c
@@ -36,13 +36,8 @@ static inline int point_is_shadowed(ray_scene_t *scene, unsigned depth, ray_3f_t
 {
 	ray_ray_t	shadow_ray;
 
-	/* negate the light vector so it's pointed at the light rather than from it */
-	shadow_ray.direction = ray_3f_negate(light_direction);
-
-	/* we must shift the origin slightly (epsilon) towards the light to
-	 * prevent spurious self-obstruction at the ray:object intersection */
-	shadow_ray.origin = ray_3f_mult_scalar(&shadow_ray.direction, 0.00001f);
-	shadow_ray.origin = ray_3f_add(&shadow_ray.origin, point);
+	shadow_ray.direction = *light_direction;
+	shadow_ray.origin = *point;
 
 	if (ray_is_obstructed(scene, depth + 1, &shadow_ray, distance))
 		return 1;
@@ -85,13 +80,14 @@ static inline ray_color_t shade_intersection(ray_scene_t *scene, ray_object_t *o
 #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);
 
 			if (rvec_lvec_dot > 0) {
+				ray_color_t	specular;
+
 				/* FIXME: assumes light is a point for its color */
 				specular = ray_3f_mult_scalar(&scene->lights[i].light.emitter.point.surface.color, approx_powf(rvec_lvec_dot, surface.highlight_exponent));
 				specular = ray_3f_mult_scalar(&specular, surface.specular);
@@ -178,7 +174,7 @@ static inline ray_color_t trace_ray(ray_scene_t *scene, ray_ray_t *primary_ray)
 			ray_3f_t	rvec;
 
 			rvec = ray_3f_mult_scalar(&ray->direction, nearest_distance);
-			intersection = ray_3f_sub(&ray->origin, &rvec);
+			intersection = ray_3f_add(&ray->origin, &rvec);
 			normal = ray_object_normal(nearest_object, &intersection);
 
 			more_color = shade_intersection(scene, nearest_object, ray, &intersection, &normal, depth, &reflectivity);