Files
blender/intern/cycles/kernel/closure/bsdf_principled_diffuse.h
Mikhail Matrosov ca0450feef Fix T91064: Cycles low poly meshes having black edges when shade smoothed
Fixes:{T91064}

Caused by {rBcd118c5581f482afc8554ff88b5b6f3b552b1682}

- Applies `ensure_valid_reflection()` to the normal input on all BSDFs for CPU and GPU.
- This doesn't affect hair.
- Removes `ensure_valid_reflection()` from the output of Bump Map and Normal Map nodes for CPU/GPU as it is not needed.
- The fix doesn't touch OSL.

Reviewed By: brecht, leesonw

Maniphest Tasks: T91064

Differential Revision: https://developer.blender.org/D12403
2021-10-06 10:25:09 +02:00

133 lines
4.2 KiB
C

/*
* Copyright 2011-2017 Blender Foundation
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#pragma once
/* DISNEY PRINCIPLED DIFFUSE BRDF
*
* Shading model by Brent Burley (Disney): "Physically Based Shading at Disney" (2012)
*/
#include "kernel/closure/bsdf_util.h"
CCL_NAMESPACE_BEGIN
typedef ccl_addr_space struct PrincipledDiffuseBsdf {
SHADER_CLOSURE_BASE;
float roughness;
} PrincipledDiffuseBsdf;
static_assert(sizeof(ShaderClosure) >= sizeof(PrincipledDiffuseBsdf),
"PrincipledDiffuseBsdf is too large!");
ccl_device float3 calculate_principled_diffuse_brdf(
const PrincipledDiffuseBsdf *bsdf, float3 N, float3 V, float3 L, float *pdf)
{
float NdotL = dot(N, L);
if (NdotL <= 0) {
return make_float3(0.0f, 0.0f, 0.0f);
}
float NdotV = dot(N, V);
/* H = normalize(L + V); // Bissector of an angle between L and V
* LH2 = 2 * dot(L, H)^2 = 2cos(x)^2 = cos(2x) + 1 = dot(L, V) + 1,
* half-angle x between L and V is at most 90 deg
*/
float LH2 = dot(L, V) + 1;
float FL = schlick_fresnel(NdotL), FV = schlick_fresnel(NdotV);
const float Fd90 = 0.5f + LH2 * bsdf->roughness;
float Fd = (1.0f - FL + Fd90 * FL) * (1.0f - FV + Fd90 * FV);
float value = M_1_PI_F * NdotL * Fd;
return make_float3(value, value, value);
}
ccl_device int bsdf_principled_diffuse_setup(PrincipledDiffuseBsdf *bsdf)
{
bsdf->type = CLOSURE_BSDF_PRINCIPLED_DIFFUSE_ID;
return SD_BSDF | SD_BSDF_HAS_EVAL;
}
ccl_device float3 bsdf_principled_diffuse_eval_reflect(const ShaderClosure *sc,
const float3 I,
const float3 omega_in,
float *pdf)
{
const PrincipledDiffuseBsdf *bsdf = (const PrincipledDiffuseBsdf *)sc;
float3 N = bsdf->N;
float3 V = I; // outgoing
float3 L = omega_in; // incoming
if (dot(N, omega_in) > 0.0f) {
*pdf = fmaxf(dot(N, omega_in), 0.0f) * M_1_PI_F;
return calculate_principled_diffuse_brdf(bsdf, N, V, L, pdf);
}
else {
*pdf = 0.0f;
return make_float3(0.0f, 0.0f, 0.0f);
}
}
ccl_device float3 bsdf_principled_diffuse_eval_transmit(const ShaderClosure *sc,
const float3 I,
const float3 omega_in,
float *pdf)
{
return make_float3(0.0f, 0.0f, 0.0f);
}
ccl_device int bsdf_principled_diffuse_sample(const ShaderClosure *sc,
float3 Ng,
float3 I,
float3 dIdx,
float3 dIdy,
float randu,
float randv,
float3 *eval,
float3 *omega_in,
float3 *domega_in_dx,
float3 *domega_in_dy,
float *pdf)
{
const PrincipledDiffuseBsdf *bsdf = (const PrincipledDiffuseBsdf *)sc;
float3 N = bsdf->N;
sample_cos_hemisphere(N, randu, randv, omega_in, pdf);
if (dot(Ng, *omega_in) > 0) {
*eval = calculate_principled_diffuse_brdf(bsdf, N, I, *omega_in, pdf);
#ifdef __RAY_DIFFERENTIALS__
// TODO: find a better approximation for the diffuse bounce
*domega_in_dx = -((2 * dot(N, dIdx)) * N - dIdx);
*domega_in_dy = -((2 * dot(N, dIdy)) * N - dIdy);
#endif
}
else {
*pdf = 0.0f;
}
return LABEL_REFLECT | LABEL_DIFFUSE;
}
CCL_NAMESPACE_END