diff options
| -rw-r--r-- | src/modules/ray/ray_object_sphere.h | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/src/modules/ray/ray_object_sphere.h b/src/modules/ray/ray_object_sphere.h index cb8e665..aadda18 100644 --- a/src/modules/ray/ray_object_sphere.h +++ b/src/modules/ray/ray_object_sphere.h @@ -17,6 +17,7 @@ typedef struct ray_object_sphere_t { float radius; struct { float r2; + float r_inv; } _prepared; } ray_object_sphere_t; @@ -24,6 +25,9 @@ typedef struct ray_object_sphere_t { static void ray_object_sphere_prepare(ray_object_sphere_t *sphere) { sphere->_prepared.r2 = sphere->radius * sphere->radius; + + /* to divide by radius via multiplication in ray_object_sphere_normal() */ + sphere->_prepared.r_inv = 1.0f / sphere->radius; } @@ -57,7 +61,7 @@ static inline ray_3f_t ray_object_sphere_normal(ray_object_sphere_t *sphere, ray ray_3f_t normal; normal = ray_3f_sub(point, &sphere->center); - normal = ray_3f_div_scalar(&normal, sphere->radius); /* normalize without the sqrt() */ + normal = ray_3f_mult_scalar(&normal, sphere->_prepared.r_inv); /* normalize without the sqrt() */ return normal; } |