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
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
|
/*
* Adapted from Open Shading Language with this license:
*
* Copyright (c) 2009-2010 Sony Pictures Imageworks Inc., et al.
* All Rights Reserved.
*
* Modifications Copyright 2012, 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.
*/
#pragma once
CCL_NAMESPACE_BEGIN
#ifdef __OSL__
typedef ccl_addr_space struct PhongRampBsdf {
SHADER_CLOSURE_BASE;
float exponent;
float3 *colors;
} PhongRampBsdf;
static_assert(sizeof(ShaderClosure) >= sizeof(PhongRampBsdf), "PhongRampBsdf is too large!");
ccl_device float3 bsdf_phong_ramp_get_color(const float3 colors[8], float pos)
{
int MAXCOLORS = 8;
float npos = pos * (float)(MAXCOLORS - 1);
int ipos = float_to_int(npos);
if (ipos < 0)
return colors[0];
if (ipos >= (MAXCOLORS - 1))
return colors[MAXCOLORS - 1];
float offset = npos - (float)ipos;
return colors[ipos] * (1.0f - offset) + colors[ipos + 1] * offset;
}
ccl_device int bsdf_phong_ramp_setup(PhongRampBsdf *bsdf)
{
bsdf->type = CLOSURE_BSDF_PHONG_RAMP_ID;
bsdf->exponent = max(bsdf->exponent, 0.0f);
return SD_BSDF | SD_BSDF_HAS_EVAL;
}
ccl_device float3 bsdf_phong_ramp_eval_reflect(const ShaderClosure *sc,
const float3 I,
const float3 omega_in,
float *pdf)
{
const PhongRampBsdf *bsdf = (const PhongRampBsdf *)sc;
float m_exponent = bsdf->exponent;
float cosNI = dot(bsdf->N, omega_in);
float cosNO = dot(bsdf->N, I);
if (cosNI > 0 && cosNO > 0) {
// reflect the view vector
float3 R = (2 * cosNO) * bsdf->N - I;
float cosRI = dot(R, omega_in);
if (cosRI > 0) {
float cosp = powf(cosRI, m_exponent);
float common = 0.5f * M_1_PI_F * cosp;
float out = cosNI * (m_exponent + 2) * common;
*pdf = (m_exponent + 1) * common;
return bsdf_phong_ramp_get_color(bsdf->colors, cosp) * out;
}
}
return make_float3(0.0f, 0.0f, 0.0f);
}
ccl_device float3 bsdf_phong_ramp_eval_transmit(const ShaderClosure *sc,
const float3 I,
const float3 omega_in,
float *pdf)
{
return make_float3(0.0f, 0.0f, 0.0f);
}
ccl_device int bsdf_phong_ramp_sample(const ShaderClosure *sc,
float3 Ng,
float3 I,
float3 dIdx,
float3 dIdy,
float randu,
float randv,
float3 *eval,
float3 *omega_in,
float3 *domega_in_dx,
float3 *domega_in_dy,
float *pdf)
{
const PhongRampBsdf *bsdf = (const PhongRampBsdf *)sc;
float cosNO = dot(bsdf->N, I);
float m_exponent = bsdf->exponent;
if (cosNO > 0) {
// reflect the view vector
float3 R = (2 * cosNO) * bsdf->N - I;
# ifdef __RAY_DIFFERENTIALS__
*domega_in_dx = (2 * dot(bsdf->N, dIdx)) * bsdf->N - dIdx;
*domega_in_dy = (2 * dot(bsdf->N, dIdy)) * bsdf->N - dIdy;
# endif
float3 T, B;
make_orthonormals(R, &T, &B);
float phi = M_2PI_F * randu;
float cosTheta = powf(randv, 1 / (m_exponent + 1));
float sinTheta2 = 1 - cosTheta * cosTheta;
float sinTheta = sinTheta2 > 0 ? sqrtf(sinTheta2) : 0;
*omega_in = (cosf(phi) * sinTheta) * T + (sinf(phi) * sinTheta) * B + (cosTheta)*R;
if (dot(Ng, *omega_in) > 0.0f) {
// common terms for pdf and eval
float cosNI = dot(bsdf->N, *omega_in);
// make sure the direction we chose is still in the right hemisphere
if (cosNI > 0) {
float cosp = powf(cosTheta, m_exponent);
float common = 0.5f * M_1_PI_F * cosp;
*pdf = (m_exponent + 1) * common;
float out = cosNI * (m_exponent + 2) * common;
*eval = bsdf_phong_ramp_get_color(bsdf->colors, cosp) * out;
}
}
}
return LABEL_REFLECT | LABEL_GLOSSY;
}
#endif /* __OSL__ */
CCL_NAMESPACE_END
|
