Files
blender/intern/cycles/kernel/svm/svm_fresnel.h
Patrick Mours 2b999c6a68 Cycles: change svm node decoding for more efficient code generation on GPU
These functions no longer accept NULL. They were renamed for clarity and to
avoid hidden merge issues.

Ref D5363
2019-08-26 10:26:53 +02:00

78 lines
2.4 KiB
C

/*
* Copyright 2011-2013 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.
*/
CCL_NAMESPACE_BEGIN
/* Fresnel Node */
ccl_device void svm_node_fresnel(
ShaderData *sd, float *stack, uint ior_offset, uint ior_value, uint node)
{
uint normal_offset, out_offset;
svm_unpack_node_uchar2(node, &normal_offset, &out_offset);
float eta = (stack_valid(ior_offset)) ? stack_load_float(stack, ior_offset) :
__uint_as_float(ior_value);
float3 normal_in = stack_valid(normal_offset) ? stack_load_float3(stack, normal_offset) : sd->N;
eta = fmaxf(eta, 1e-5f);
eta = (sd->flag & SD_BACKFACING) ? 1.0f / eta : eta;
float f = fresnel_dielectric_cos(dot(sd->I, normal_in), eta);
stack_store_float(stack, out_offset, f);
}
/* Layer Weight Node */
ccl_device void svm_node_layer_weight(ShaderData *sd, float *stack, uint4 node)
{
uint blend_offset = node.y;
uint blend_value = node.z;
uint type, normal_offset, out_offset;
svm_unpack_node_uchar3(node.w, &type, &normal_offset, &out_offset);
float blend = (stack_valid(blend_offset)) ? stack_load_float(stack, blend_offset) :
__uint_as_float(blend_value);
float3 normal_in = (stack_valid(normal_offset)) ? stack_load_float3(stack, normal_offset) :
sd->N;
float f;
if (type == NODE_LAYER_WEIGHT_FRESNEL) {
float eta = fmaxf(1.0f - blend, 1e-5f);
eta = (sd->flag & SD_BACKFACING) ? eta : 1.0f / eta;
f = fresnel_dielectric_cos(dot(sd->I, normal_in), eta);
}
else {
f = fabsf(dot(sd->I, normal_in));
if (blend != 0.5f) {
blend = clamp(blend, 0.0f, 1.0f - 1e-5f);
blend = (blend < 0.5f) ? 2.0f * blend : 0.5f / (1.0f - blend);
f = powf(f, blend);
}
f = 1.0f - f;
}
stack_store_float(stack, out_offset, f);
}
CCL_NAMESPACE_END