Fix T36979: wrong render of textured mesh lights with multiple importance sampling.

This commit is contained in:
Brecht Van Lommel 2014-02-07 15:08:50 +01:00
parent 52bae9691b
commit 9c83ed774b
Notes: blender-bot 2023-05-29 09:17:12 +02:00
Referenced by issue #36979, Obscura (Pinhole camera) produces incorrect results with emission texture
3 changed files with 24 additions and 21 deletions

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@ -19,7 +19,7 @@ CCL_NAMESPACE_BEGIN
/* Direction Emission */
ccl_device_noinline float3 direct_emissive_eval(KernelGlobals *kg, float rando,
LightSample *ls, float u, float v, float3 I, differential3 dI, float t, float time, int bounce)
LightSample *ls, float3 I, differential3 dI, float t, float time, int bounce)
{
/* setup shading at emitter */
ShaderData sd;
@ -47,10 +47,10 @@ ccl_device_noinline float3 direct_emissive_eval(KernelGlobals *kg, float rando,
{
#ifdef __HAIR__
if(ls->type == LIGHT_STRAND)
shader_setup_from_sample(kg, &sd, ls->P, ls->Ng, I, ls->shader, ls->object, ls->prim, u, v, t, time, bounce+1, ls->prim);
shader_setup_from_sample(kg, &sd, ls->P, ls->Ng, I, ls->shader, ls->object, ls->prim, ls->u, ls->v, t, time, bounce+1, ls->prim);
else
#endif
shader_setup_from_sample(kg, &sd, ls->P, ls->Ng, I, ls->shader, ls->object, ls->prim, u, v, t, time, bounce+1, ~0);
shader_setup_from_sample(kg, &sd, ls->P, ls->Ng, I, ls->shader, ls->object, ls->prim, ls->u, ls->v, t, time, bounce+1, ~0);
ls->Ng = sd.Ng;
@ -95,7 +95,7 @@ ccl_device_noinline bool direct_emission(KernelGlobals *kg, ShaderData *sd, int
differential3 dD = differential3_zero();
/* evaluate closure */
float3 light_eval = direct_emissive_eval(kg, rando, &ls, randu, randv, -ls.D, dD, ls.t, sd->time, bounce);
float3 light_eval = direct_emissive_eval(kg, rando, &ls, -ls.D, dD, ls.t, sd->time, bounce);
if(is_zero(light_eval))
return false;
@ -211,10 +211,7 @@ ccl_device_noinline bool indirect_lamp_emission(KernelGlobals *kg, Ray *ray, int
}
#endif
/* todo: missing texture coordinates */
float u = 0.0f;
float v = 0.0f;
float3 L = direct_emissive_eval(kg, 0.0f, &ls, u, v, -ray->D, ray->dD, ls.t, ray->time, bounce);
float3 L = direct_emissive_eval(kg, 0.0f, &ls, -ray->D, ray->dD, ls.t, ray->time, bounce);
if(!(path_flag & PATH_RAY_MIS_SKIP)) {
/* multiple importance sampling, get regular light pdf,

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@ -23,6 +23,7 @@ typedef struct LightSample {
float3 Ng; /* normal on light */
float3 D; /* direction from shading point to light */
float t; /* distance to light (FLT_MAX for distant light) */
float u, v; /* parametric coordinate on primitive */
float pdf; /* light sampling probability density function */
float eval_fac; /* intensity multiplier */
int object; /* object id for triangle/curve lights */
@ -219,6 +220,8 @@ ccl_device void lamp_light_sample(KernelGlobals *kg, int lamp,
ls->object = ~0;
ls->prim = ~0;
ls->lamp = lamp;
ls->u = randu;
ls->v = randv;
if(type == LIGHT_DISTANT) {
/* distant light */
@ -309,6 +312,9 @@ ccl_device bool lamp_light_eval(KernelGlobals *kg, int lamp, float3 P, float3 D,
ls->object = ~0;
ls->prim = ~0;
ls->lamp = lamp;
/* todo: missing texture coordinates */
ls->u = 0.0f;
ls->v = 0.0f;
if(!(ls->shader & SHADER_USE_MIS))
return false;
@ -443,14 +449,24 @@ ccl_device void object_transform_light_sample(KernelGlobals *kg, LightSample *ls
ccl_device void triangle_light_sample(KernelGlobals *kg, int prim, int object,
float randu, float randv, float time, LightSample *ls)
{
float u, v;
/* compute random point in triangle */
randu = sqrtf(randu);
u = 1.0f - randu;
v = randv*randu;
/* triangle, so get position, normal, shader */
ls->P = triangle_sample_MT(kg, prim, randu, randv);
ls->P = triangle_point_MT(kg, prim, u, v);
ls->Ng = triangle_normal_MT(kg, prim, &ls->shader);
ls->object = object;
ls->prim = prim;
ls->lamp = ~0;
ls->shader |= SHADER_USE_MIS;
ls->t = 0.0f;
ls->u = u;
ls->v = v;
ls->type = LIGHT_TRIANGLE;
ls->eval_fac = 1.0f;
@ -504,6 +520,8 @@ ccl_device void curve_segment_light_sample(KernelGlobals *kg, int prim, int obje
ls->prim = prim;
ls->lamp = ~0;
ls->t = 0.0f;
ls->u = randu;
ls->v = randv;
ls->type = LIGHT_STRAND;
ls->eval_fac = 1.0f;
ls->shader = __float_as_int(v00.z) | SHADER_USE_MIS;

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@ -31,18 +31,6 @@ ccl_device_inline float3 triangle_point_MT(KernelGlobals *kg, int tri_index, flo
return (u*v0 + v*v1 + t*v2);
}
/* Sample point on triangle */
ccl_device_inline float3 triangle_sample_MT(KernelGlobals *kg, int tri_index, float randu, float randv)
{
/* compute point */
randu = sqrtf(randu);
float u = 1.0f - randu;
float v = randv*randu;
return triangle_point_MT(kg, tri_index, u, v);
}
/* Normal for Moller-Trumbore triangles */
ccl_device_inline float3 triangle_normal_MT(KernelGlobals *kg, int tri_index, int *shader)
{