forked from bartvdbraak/blender
43 lines
1.2 KiB
Plaintext
43 lines
1.2 KiB
Plaintext
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/*
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* Copyright 2011, Blender Foundation.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version 2
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* of the License, or (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software Foundation,
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* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
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*/
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#include "stdosl.h"
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#include "node_fresnel.h"
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shader node_blend_weight(
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float Blend = 0.3,
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normal Normal = N,
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output float Fresnel = 0.0,
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output float Facing = 0.0)
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{
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float f = max(1.0 - Blend, 1e-5);
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Fresnel = fresnel_dielectric(I, Normal, backfacing()? f: 1.0/f);
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Facing = abs(dot(I, Normal));
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if(Blend != 0.5) {
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Blend = clamp(Blend, 0.0, 1.0);
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Blend = (Blend < 0.5)? 2.0*Blend: 0.5/(1.0 - Blend);
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Facing = powf(Facing, Blend);
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}
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Facing = 1.0 - Facing;
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}
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