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Diffstat (limited to 'intern/cycles/kernel/osl/emissive.cpp')
-rw-r--r-- | intern/cycles/kernel/osl/emissive.cpp | 107 |
1 files changed, 107 insertions, 0 deletions
diff --git a/intern/cycles/kernel/osl/emissive.cpp b/intern/cycles/kernel/osl/emissive.cpp new file mode 100644 index 00000000000..28d3c73e59b --- /dev/null +++ b/intern/cycles/kernel/osl/emissive.cpp @@ -0,0 +1,107 @@ +/* + * 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. + */ + +#include <OpenImageIO/fmath.h> + +#include <OSL/genclosure.h> + +#include "osl_closures.h" + +CCL_NAMESPACE_BEGIN + +using namespace OSL; + +/// Variable cone emissive closure +/// +/// This primitive emits in a cone having a configurable +/// penumbra area where the light decays to 0 reaching the +/// outer_angle limit. It can also behave as a lambertian emitter +/// if the provided angles are PI/2, which is the default +/// +class GenericEmissiveClosure : public EmissiveClosure { +public: + GenericEmissiveClosure() { } + + void setup() { } + + size_t memsize () const { return sizeof(*this); } + + const char *name () const { return "emission"; } + + void print_on (std::ostream &out) const { + out << name() << "()"; + } + + Color3 eval (const Vec3 &Ng, const Vec3 &omega_out) const + { + float cosNO = fabsf(Ng.dot(omega_out)); + float res = cosNO > 0 ? 1.0f / float(M_PI) : 0.0f; + return Color3(res, res, res); + } + + void sample (const Vec3 &Ng, float randu, float randv, + Vec3 &omega_out, float &pdf) const + { + // We don't do anything sophisticated here for the step + // We just sample the whole cone uniformly to the cosine + Vec3 T, B; + make_orthonormals(Ng, T, B); + float phi = 2 * (float) M_PI * randu; + float cosTheta = sqrtf(1.0f - 1.0f * randv); + float sinTheta = sqrtf(1.0f - cosTheta * cosTheta); + omega_out = (cosf(phi) * sinTheta) * T + + (sinf(phi) * sinTheta) * B + + cosTheta * Ng; + pdf = 1.0f / float(M_PI); + } + + /// Return the probability distribution function in the direction omega_out, + /// given the parameters and the light's surface normal. This MUST match + /// the PDF computed by sample(). + float pdf (const Vec3 &Ng, + const Vec3 &omega_out) const + { + float cosNO = Ng.dot(omega_out); + return cosNO > 0 ? 1.0f / float(M_PI) : 0.0f; + } +}; + + + +ClosureParam closure_emission_params[] = { + CLOSURE_STRING_KEYPARAM("label"), + CLOSURE_FINISH_PARAM(GenericEmissiveClosure) }; + +CLOSURE_PREPARE(closure_emission_prepare, GenericEmissiveClosure) + +CCL_NAMESPACE_END + |