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
|
/* SPDX-License-Identifier: BSD-3-Clause
*
* Adapted from Open Shading Language
* Copyright (c) 2009-2010 Sony Pictures Imageworks Inc., et al.
* All Rights Reserved.
*
* Modifications Copyright 2011-2022 Blender Foundation. */
#pragma once
CCL_NAMESPACE_BEGIN
/* REFRACTION */
ccl_device int bsdf_refraction_setup(ccl_private MicrofacetBsdf *bsdf)
{
bsdf->type = CLOSURE_BSDF_REFRACTION_ID;
return SD_BSDF;
}
ccl_device Spectrum bsdf_refraction_eval(ccl_private const ShaderClosure *sc,
const float3 I,
const float3 omega_in,
ccl_private float *pdf)
{
*pdf = 0.0f;
return zero_spectrum();
}
ccl_device int bsdf_refraction_sample(ccl_private const ShaderClosure *sc,
float3 Ng,
float3 I,
float randu,
float randv,
ccl_private Spectrum *eval,
ccl_private float3 *omega_in,
ccl_private float *pdf,
ccl_private float *eta)
{
ccl_private const MicrofacetBsdf *bsdf = (ccl_private const MicrofacetBsdf *)sc;
float m_eta = bsdf->ior;
*eta = 1.0f / m_eta;
float3 N = bsdf->N;
float3 R, T;
bool inside;
float fresnel;
fresnel = fresnel_dielectric(m_eta, N, I, &R, &T, &inside);
if (!inside && fresnel != 1.0f) {
/* Some high number for MIS. */
*pdf = 1e6f;
*eval = make_spectrum(1e6f);
*omega_in = T;
}
else {
*pdf = 0.0f;
*eval = zero_spectrum();
}
return LABEL_TRANSMIT | LABEL_SINGULAR;
}
CCL_NAMESPACE_END
|