rendering-in-cgi/Framework/lights/ambient_light.cpp
2024-04-23 10:14:24 +02:00

77 lines
2.5 KiB
C++

// Copyright 2009-2021 Intel Corporation
// SPDX-License-Identifier: Apache-2.0
#include "light.h"
#include <sampling.hpp>
#include <math/linearspace3.h>
#include "helper.hpp"
namespace embree {
struct AmbientLight {
Light super; //!< inherited light fields
Vec3fa radiance; //!< RGB color and intensity of light
};
// Implementation
//////////////////////////////////////////////////////////////////////////////
// XXX importance sampling is only done into the positive hemisphere
// ==> poor support for translucent materials
Light_SampleRes AmbientLight_sample(const Light* super,
const Sample& dg,
const Vec2f& s) {
AmbientLight* self = (AmbientLight *) super;
Light_SampleRes res;
const Vec3fa localDir = cosineSampleHemisphere(s);
res.dir = frame(dg.Ns) * localDir;
res.pdf = cosineSampleHemispherePDF(localDir);
res.dist = inf;
res.weight = self->radiance * rcp(res.pdf);
return res;
}
Light_EvalRes AmbientLight_eval(const Light* super,
const Sample& dg,
const Vec3fa& dir) {
AmbientLight* self = (AmbientLight *) super;
Light_EvalRes res;
res.value = self->radiance;
res.dist = inf;
res.pdf = cosineSampleHemispherePDF(max(dot(dg.Ns, dir), 0.f));
return res;
}
void AmbientLight_Constructor(AmbientLight* self,
const Vec3fa& radiance) {
Light_Constructor(&self->super);
self->radiance = radiance;
//self->super.sample = GET_FUNCTION_POINTER(AmbientLight_sample);
//self->super.eval = GET_FUNCTION_POINTER(AmbientLight_eval);
self->super.type = LIGHT_AMBIENT;
}
// Exports (called from C++)
//////////////////////////////////////////////////////////////////////////////
//! Create an ispc-side AmbientLight object
extern "C" void* AmbientLight_create() {
AmbientLight* self = (AmbientLight *) alignedUSMMalloc(sizeof(AmbientLight), 16);
AmbientLight_Constructor(self, Vec3fa(1.f));
return self;
}
//! Set the parameters of an ispc-side AmbientLight object
extern "C" void AmbientLight_set(void* super,
const Vec3fa& radiance) {
AmbientLight* self = (AmbientLight *) super;
self->radiance = radiance;
}
} // namespace embree