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
|
/*
* Copyright 2011, Blender Foundation.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
CCL_NAMESPACE_BEGIN
/* Fresnel Node */
__device void svm_node_fresnel(ShaderData *sd, float *stack, uint ior_offset, uint ior_value, uint out_offset)
{
float eta = (stack_valid(ior_offset))? stack_load_float(stack, ior_offset): __int_as_float(ior_value);
eta = fmaxf(eta, 1.0f + 1e-5f);
eta = (sd->flag & SD_BACKFACING)? 1.0f/eta: eta;
float f = fresnel_dielectric_cos(dot(sd->I, sd->N), eta);
stack_store_float(stack, out_offset, f);
}
/* Blend Weight Node */
__device void svm_node_layer_weight(ShaderData *sd, float *stack, uint4 node)
{
uint blend_offset = node.y;
uint blend_value = node.z;
float blend = (stack_valid(blend_offset))? stack_load_float(stack, blend_offset): __int_as_float(blend_value);
uint type, out_offset;
decode_node_uchar4(node.w, &type, &out_offset, NULL, NULL);
float f;
if(type == NODE_LAYER_WEIGHT_FRESNEL) {
float eta = fmaxf(1.0f - blend, 1e-5f);
eta = (sd->flag & SD_BACKFACING)? eta: 1.0f/eta;
f = fresnel_dielectric_cos(dot(sd->I, sd->N), eta);
}
else {
f = fabsf(dot(sd->I, sd->N));
if(blend != 0.5f) {
blend = clamp(blend, 0.0f, 1.0f);
blend = (blend < 0.5f)? 2.0f*blend: 0.5f/(1.0f - blend);
f = powf(f, blend);
}
f = 1.0f - f;
}
stack_store_float(stack, out_offset, f);
}
CCL_NAMESPACE_END
|
