griefith/test2
1
0
Fork 0
Code Issues Pull Requests Actions 1 Packages Projects Releases Wiki Activity

Cleanup: rearrange code in bsdf_microfacet.h for better readability

Browse Source 
1. move early-out logic even earlier
2. reduced the scope of some variables
3. return `label` at the end of `bsdf_microfacet_sample()`. Return
`LABEL_NONE` in the invalid case. The previous distinction was
unnecessary because samples with zero contribution are assigned with
`LABEL_NONE` in `integrate_surface_bsdf_bssrdf_bounce()` anyway.
This commit is contained in:
Weizhen Huang
2023-09-07 17:58:31 +02:00
parent bf82f9442c
commit 21ca47d81f
1 changed files with 17 additions and 27 deletions
Download Patch File Download Diff File Expand all files Collapse all files

44
intern/cycles/kernel/closure/bsdf_microfacet.h
View File

@@ -582,32 +582,28 @@ ccl_device int bsdf_microfacet_sample(ccl_private const ShaderClosure *sc,
{
ccl_private const MicrofacetBsdf *bsdf = (ccl_private const MicrofacetBsdf *)sc;
const float3 N = bsdf->N;
const float cos_NI = dot(N, wi);
if (cos_NI <= 0) {
/* Incident angle from the lower hemisphere is invalid. */
return LABEL_NONE;
}
const float m_eta = bsdf->ior;
const bool m_refraction = CLOSURE_IS_REFRACTION(bsdf->type);
const bool m_glass = CLOSURE_IS_GLASS(bsdf->type);
const bool m_reflection = !(m_refraction || m_glass);
const float alpha_x = bsdf->alpha_x;
const float alpha_y = bsdf->alpha_y;
bool m_singular = !bsdf_microfacet_eval_flag(bsdf);
const float3 N = bsdf->N;
const float cos_NI = dot(N, wi);
if (cos_NI <= 0) {
*eval = zero_spectrum();
*pdf = 0.0f;
return (m_reflection ? LABEL_REFLECT : LABEL_TRANSMIT) |
(m_singular ? LABEL_SINGULAR : LABEL_GLOSSY);
}
float3 H;
float cos_NH, cos_HI;
float3 local_H, local_I, X, Y; /* Needed for anisotropic microfacets later. */
/* Needed for anisotropic microfacets later. */
float3 local_H, local_I;
if (m_singular) {
H = N;
cos_NH = 1.0f;
cos_HI = cos_NI;
}
else {
float3 X, Y;
if (alpha_x == alpha_y) {
make_orthonormals(N, &X, &Y);
}
@@ -627,8 +623,6 @@ ccl_device int bsdf_microfacet_sample(ccl_private const ShaderClosure *sc,
}
H = X * local_H.x + Y * local_H.y + N * local_H.z;
cos_NH = local_H.z;
cos_HI = dot(H, wi);
}
bool valid;
@@ -657,12 +651,11 @@ ccl_device int bsdf_microfacet_sample(ccl_private const ShaderClosure *sc,
lobe_pdf = 1.0f;
do_refract = false;
}
const float cos_HI = dot(H, wi);
int label;
if (do_refract) {
/* wo was already set to the refracted direction by fresnel_dielectric. */
// valid = valid && (dot(Ng, *wo) < 0);
label = LABEL_TRANSMIT;
/* If the IOR is close enough to 1.0, just treat the interaction as specular. */
m_singular = m_singular || (fabsf(m_eta - 1.0f) < 1e-4f);
}
@@ -670,29 +663,25 @@ ccl_device int bsdf_microfacet_sample(ccl_private const ShaderClosure *sc,
/* Eq. 39 - compute actual reflected direction */
*wo = 2 * cos_HI * H - wi;
valid = valid && (dot(Ng, *wo) > 0);
label = LABEL_REFLECT;
}
if (!valid) {
*eval = zero_spectrum();
*pdf = 0.0f;
return label | (m_singular ? LABEL_SINGULAR : LABEL_GLOSSY);
return LABEL_NONE;
}
if (m_singular) {
label |= LABEL_SINGULAR;
/* Some high number for MIS. */
*pdf = lobe_pdf * 1e6f;
*eval = make_spectrum(1e6f) * microfacet_fresnel(bsdf, wi, H, do_refract);
}
else {
label |= LABEL_GLOSSY;
float cos_NO = dot(N, *wo);
float D, lambdaI, lambdaO;
/* TODO: add support for anisotropic transmission. */
if (alpha_x == alpha_y || do_refract) { /* Isotropic. */
float alpha2 = alpha_x * alpha_y;
const float cos_NH = dot(N, H);
const float cos_NO = dot(N, *wo);
if (bsdf->type == CLOSURE_BSDF_MICROFACET_GGX_CLEARCOAT_ID) {
D = bsdf_clearcoat_D(alpha2, cos_NH);
@@ -709,7 +698,7 @@ ccl_device int bsdf_microfacet_sample(ccl_private const ShaderClosure *sc,
lambdaI = bsdf_lambda<m_type>(alpha2, cos_NI);
}
else { /* Anisotropic. */
const float3 local_O = make_float3(dot(X, *wo), dot(Y, *wo), cos_NO);
const float3 local_O = 2.0f * cos_HI * local_H - local_I;
D = bsdf_aniso_D<m_type>(alpha_x, alpha_y, local_H);
@@ -731,7 +720,8 @@ ccl_device int bsdf_microfacet_sample(ccl_private const ShaderClosure *sc,
*sampled_roughness = make_float2(alpha_x, alpha_y);
*eta = do_refract ? 1.0f / m_eta : m_eta;
return label;
return (do_refract ? LABEL_TRANSMIT : LABEL_REFLECT) |
(m_singular ? LABEL_SINGULAR : LABEL_GLOSSY);
}
/* Fresnel term setup functions. These get called after the distribution-specific setup functions