39 lines
1.3 KiB
Plaintext
39 lines
1.3 KiB
Plaintext
/*
|
|
* Copyright 2011-2014 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
|
|
*/
|
|
|
|
color fresnel_conductor(float cosi, color eta, color k)
|
|
{
|
|
color cosi2 = color(cosi * cosi);
|
|
color one = color(1, 1, 1);
|
|
color tmp_f = eta * eta + k * k;
|
|
color tmp = tmp_f * cosi2;
|
|
color Rparl2 = (tmp - (2.0 * eta * cosi) + one) /
|
|
(tmp + (2.0 * eta * cosi) + one);
|
|
color Rperp2 = (tmp_f - (2.0 * eta * cosi) + cosi2) /
|
|
(tmp_f + (2.0 * eta * cosi) + cosi2);
|
|
return (Rparl2 + Rperp2) * 0.5;
|
|
}
|
|
|
|
shader node_fresnel_conductive(
|
|
color n = color(0.084136, 0.410708, 1.472421),
|
|
color k = color(4.018579, 2.363371, 1.607574),
|
|
normal Normal = N,
|
|
output color Color = color(0.8, 0.8, 0.8))
|
|
{
|
|
float cosi = dot(I, Normal);
|
|
Color = fresnel_conductor(cosi, n, k);
|
|
}
|