diff options
| author | Vito Caputo <vcaputo@pengaru.com> | 2017-09-16 09:35:20 -0700 |
|---|---|---|
| committer | Vito Caputo <vcaputo@pengaru.com> | 2017-09-17 17:58:07 -0700 |
| commit | fc1a7bc862121c81a4b1e6075c9c0d3381e2f1bb (patch) | |
| tree | 4696e54fda172b4310f608dc8fa860def31b0a52 | |
| parent | 337440d4a0f141c036e057ecc4fe4f4b808ff9c0 (diff) | |
ray: stop recurring below a relevance threshold
There's no point computing more reflections if they're not going
to contribute substantially to the resulting sample. Previously
the max depth threshold solely controlled how many times a given
ray could reflect, this commit introduces a minimum relevance as
well. Value may require tuning, may actually make sense to move
into the scene description as a parameter.
Brings a minor frame rate improvement.
| -rw-r--r-- | src/modules/ray/ray_scene.c | 6 |
1 files changed, 2 insertions, 4 deletions
diff --git a/src/modules/ray/ray_scene.c b/src/modules/ray/ray_scene.c index f78ed3e..21a3bfa 100644 --- a/src/modules/ray/ray_scene.c +++ b/src/modules/ray/ray_scene.c @@ -10,7 +10,7 @@ #include "ray_scene.h" #define MAX_RECURSION_DEPTH 4 - +#define MIN_RELEVANCE 0.05f /* Determine if the ray is obstructed by an object within the supplied distance, for shadows */ @@ -163,8 +163,6 @@ static inline ray_color_t trace_ray(ray_scene_t *scene, ray_ray_t *primary_ray) reflected_ray.direction = new_direction; ray = &reflected_ray; - - relevance *= reflectivity; } nearest_object = find_nearest_intersection(scene, reflector, ray, depth, &nearest_distance); @@ -182,7 +180,7 @@ static inline ray_color_t trace_ray(ray_scene_t *scene, ray_ray_t *primary_ray) } reflector = nearest_object; - } while (reflector && (++depth < MAX_RECURSION_DEPTH)); + } while (reflector && (++depth < MAX_RECURSION_DEPTH) && (relevance *= reflectivity) >= MIN_RELEVANCE); return color; } |