diff options
| -rw-r--r-- | intern/cycles/kernel/kernel_light.h | 31 |
1 files changed, 10 insertions, 21 deletions
diff --git a/intern/cycles/kernel/kernel_light.h b/intern/cycles/kernel/kernel_light.h index cd05e29ca54..d03cfa92319 100644 --- a/intern/cycles/kernel/kernel_light.h +++ b/intern/cycles/kernel/kernel_light.h @@ -807,9 +807,7 @@ ccl_device_forceinline float triangle_light_pdf(KernelGlobals *kg, ShaderData *s { /* A naive heuristic to decide between costly solid angle sampling * and simple area sampling, comparing the distance to the triangle plane - * to the length of the edtes of the triangle. - * Looking at two edge of the triangle should be a sufficient heuristic, - * the third edge can't possibly be longer than the sum of the other two. */ + * to the length of the edges of the triangle. */ float3 V[3]; bool has_motion = triangle_world_space_vertices(kg, sd->object, sd->prim, sd->time, V); @@ -877,9 +875,7 @@ ccl_device_forceinline void triangle_light_sample(KernelGlobals *kg, int prim, i { /* A naive heuristic to decide between costly solid angle sampling * and simple area sampling, comparing the distance to the triangle plane - * to the length of the edtes of the triangle. - * Looking at two edge of the triangle should be a sufficient heuristic, - * the third edge can't possibly be longer than the sum of the other two. */ + * to the length of the edges of the triangle. */ float3 V[3]; bool has_motion = triangle_world_space_vertices(kg, object, prim, time, V); @@ -968,21 +964,14 @@ ccl_device_forceinline void triangle_light_sample(KernelGlobals *kg, int prim, i const float z = 1.0f - randv * (1.0f - dot(C_, B)); ls->D = z * B + safe_sqrtf(1.0f - z*z) * safe_normalize(C_ - dot(C_, B) * B); - /* calculate intersection with the planar triangle - * mostly standard ray/tri intersection, with u/v clamped */ - const float3 s1 = cross(ls->D, e1); - - const float divisor = dot(s1, e0); - if(UNLIKELY(divisor == 0.0f)) { - ls->pdf = 0.0f; - return; - } - const float inv_divisor = 1.0f/divisor; - const float3 d = P - V[0]; - ls->u = clamp(dot(d, s1)*inv_divisor, 0.0f, 1.0f); - const float3 s2 = cross(d, e0); - ls->v = clamp(dot(ls->D, s2)*inv_divisor, 0.0f, 1.0f); - ls->t = dot(e1, s2)*inv_divisor; + /* calculate intersection with the planar triangle */ + ray_triangle_intersect(P, ls->D, FLT_MAX, +#if defined(__KERNEL_SSE2__) && defined(__KERNEL_SSE__) + (ssef*)V, +#else + V[0], V[1], V[2], +#endif + &ls->u, &ls->v, &ls->t); ls->P = P + ls->D * ls->t; /* pdf_triangles is calculated over triangle area, but we're sampling over solid angle */ |