blender/intern/cycles/kernel/svm/svm_gamma.h

/*
 * 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

ccl_device void svm_node_gamma(ShaderData *sd, float *stack, uint in_gamma, uint in_color, uint out_color)
{
	float3 color = stack_load_float3(stack, in_color);
	float gamma = stack_load_float(stack, in_gamma);

	if (color.x > 0.0f)
		color.x = powf(color.x, gamma);
	if (color.y > 0.0f)
		color.y = powf(color.y, gamma);
	if (color.z > 0.0f)
		color.z = powf(color.z, gamma);

	if (stack_valid(out_color))
		stack_store_float3(stack, out_color, color);
}

CCL_NAMESPACE_END