blender/intern/cycles/kernel/svm/emissive.h
2012-06-09 17:22:52 +00:00

60 lines
2.3 KiB
C

/*
* Adapted from Open Shading Language with this license:
*
* Copyright (c) 2009-2010 Sony Pictures Imageworks Inc., et al.
* All Rights Reserved.
*
* Modifications Copyright 2011, Blender Foundation.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* * Neither the name of Sony Pictures Imageworks nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
CCL_NAMESPACE_BEGIN
/* EMISSION CLOSURE */
/// Return the probability distribution function in the direction I,
/// given the parameters and the light's surface normal. This MUST match
/// the PDF computed by sample().
__device float emissive_pdf(const float3 Ng, const float3 I)
{
float cosNO = fabsf(dot(Ng, I));
return (cosNO > 0.0f)? 1.0f: 0.0f;
}
__device float3 emissive_eval(const float3 Ng, const float3 I)
{
float res = emissive_pdf(Ng, I);
return make_float3(res, res, res);
}
__device float3 svm_emissive_eval(ShaderData *sd, ShaderClosure *sc)
{
return emissive_eval(sd->Ng, sd->I);
}
CCL_NAMESPACE_END