1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
|
// Copyright 2009 Intel Corporation
// SPDX-License-Identifier: Apache-2.0
#include "common/DifferentialGeometry.ih"
#include "math/sampling.ih"
#include "rkcommon/math/LinearSpace.ih"
// c++ shared
#include "AmbientLightShared.h"
OSPRAY_BEGIN_ISPC_NAMESPACE
// Implementation
//////////////////////////////////////////////////////////////////////////////
// XXX importance sampling is only done into the positive hemisphere
// ==> poor support for translucent materials
SYCL_EXTERNAL Light_SampleRes AmbientLight_sample(const Light *uniform super,
const DifferentialGeometry &dg,
const vec2f &s,
const float,
const uniform FeatureFlagsHandler &)
{
uniform AmbientLight *uniform self = (uniform AmbientLight * uniform) super;
Light_SampleRes res;
if (reduce_max(abs(dg.Ns)) > 0) {
const vec3f localDir = cosineSampleHemisphere(s);
res.dir = frame(dg.Ns) * localDir;
res.pdf = cosineSampleHemispherePDF(localDir);
} else {
res.dir = uniformSampleSphere(1.f, s);
res.pdf = uniformSampleSpherePDF(1.f);
}
res.dist = inf;
res.weight = self->radiance * rcp(res.pdf);
return res;
}
SYCL_EXTERNAL Light_EvalRes AmbientLight_eval(const Light *uniform super,
const DifferentialGeometry &dg,
const vec3f &dir,
const float,
const float maxDist,
const float)
{
uniform AmbientLight *uniform self = (uniform AmbientLight * uniform) super;
Light_EvalRes res;
res.radiance = (float)inf <= maxDist ? self->radiance : make_vec3f(0.f);
if (reduce_max(abs(dg.Ns)) > 0)
res.pdf = cosineSampleHemispherePDF(max(dot(dg.Ns, dir), 0.f));
else
res.pdf = uniformSampleSpherePDF(1.f);
return res;
}
// Exports (called from C++)
//////////////////////////////////////////////////////////////////////////////
export void *uniform AmbientLight_sample_addr()
{
return (void *uniform)AmbientLight_sample;
}
export void *uniform AmbientLight_eval_addr()
{
return (void *uniform)AmbientLight_eval;
}
OSPRAY_END_ISPC_NAMESPACE
|
