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
|
/* SPDX-License-Identifier: Apache-2.0
* Copyright 2011-2022 Blender Foundation. */
// TODO(sergey): Look into avoid use of full Transform and use 3x3 matrix and
// 3-vector which might be faster.
ccl_device_forceinline Transform bvh_unaligned_node_fetch_space(KernelGlobals kg,
int node_addr,
int child)
{
Transform space;
const int child_addr = node_addr + child * 3;
space.x = kernel_data_fetch(bvh_nodes, child_addr + 1);
space.y = kernel_data_fetch(bvh_nodes, child_addr + 2);
space.z = kernel_data_fetch(bvh_nodes, child_addr + 3);
return space;
}
ccl_device_forceinline int bvh_aligned_node_intersect(KernelGlobals kg,
const float3 P,
const float3 idir,
const float tmin,
const float tmax,
const int node_addr,
const uint visibility,
float dist[2])
{
/* fetch node data */
#ifdef __VISIBILITY_FLAG__
float4 cnodes = kernel_data_fetch(bvh_nodes, node_addr + 0);
#endif
float4 node0 = kernel_data_fetch(bvh_nodes, node_addr + 1);
float4 node1 = kernel_data_fetch(bvh_nodes, node_addr + 2);
float4 node2 = kernel_data_fetch(bvh_nodes, node_addr + 3);
/* intersect ray against child nodes */
float c0lox = (node0.x - P.x) * idir.x;
float c0hix = (node0.z - P.x) * idir.x;
float c0loy = (node1.x - P.y) * idir.y;
float c0hiy = (node1.z - P.y) * idir.y;
float c0loz = (node2.x - P.z) * idir.z;
float c0hiz = (node2.z - P.z) * idir.z;
float c0min = max4(tmin, min(c0lox, c0hix), min(c0loy, c0hiy), min(c0loz, c0hiz));
float c0max = min4(tmax, max(c0lox, c0hix), max(c0loy, c0hiy), max(c0loz, c0hiz));
float c1lox = (node0.y - P.x) * idir.x;
float c1hix = (node0.w - P.x) * idir.x;
float c1loy = (node1.y - P.y) * idir.y;
float c1hiy = (node1.w - P.y) * idir.y;
float c1loz = (node2.y - P.z) * idir.z;
float c1hiz = (node2.w - P.z) * idir.z;
float c1min = max4(tmin, min(c1lox, c1hix), min(c1loy, c1hiy), min(c1loz, c1hiz));
float c1max = min4(tmax, max(c1lox, c1hix), max(c1loy, c1hiy), max(c1loz, c1hiz));
dist[0] = c0min;
dist[1] = c1min;
#ifdef __VISIBILITY_FLAG__
/* this visibility test gives a 5% performance hit, how to solve? */
return (((c0max >= c0min) && (__float_as_uint(cnodes.x) & visibility)) ? 1 : 0) |
(((c1max >= c1min) && (__float_as_uint(cnodes.y) & visibility)) ? 2 : 0);
#else
return ((c0max >= c0min) ? 1 : 0) | ((c1max >= c1min) ? 2 : 0);
#endif
}
ccl_device_forceinline bool bvh_unaligned_node_intersect_child(KernelGlobals kg,
const float3 P,
const float3 dir,
const float tmin,
const float tmax,
int node_addr,
int child,
float dist[2])
{
Transform space = bvh_unaligned_node_fetch_space(kg, node_addr, child);
float3 aligned_dir = transform_direction(&space, dir);
float3 aligned_P = transform_point(&space, P);
float3 nrdir = -bvh_inverse_direction(aligned_dir);
float3 lower_xyz = aligned_P * nrdir;
float3 upper_xyz = lower_xyz - nrdir;
const float near_x = min(lower_xyz.x, upper_xyz.x);
const float near_y = min(lower_xyz.y, upper_xyz.y);
const float near_z = min(lower_xyz.z, upper_xyz.z);
const float far_x = max(lower_xyz.x, upper_xyz.x);
const float far_y = max(lower_xyz.y, upper_xyz.y);
const float far_z = max(lower_xyz.z, upper_xyz.z);
const float tnear = max4(tmin, near_x, near_y, near_z);
const float tfar = min4(tmax, far_x, far_y, far_z);
*dist = tnear;
return tnear <= tfar;
}
ccl_device_forceinline int bvh_unaligned_node_intersect(KernelGlobals kg,
const float3 P,
const float3 dir,
const float3 idir,
const float tmin,
const float tmax,
const int node_addr,
const uint visibility,
float dist[2])
{
int mask = 0;
#ifdef __VISIBILITY_FLAG__
float4 cnodes = kernel_data_fetch(bvh_nodes, node_addr + 0);
#endif
if (bvh_unaligned_node_intersect_child(kg, P, dir, tmin, tmax, node_addr, 0, &dist[0])) {
#ifdef __VISIBILITY_FLAG__
if ((__float_as_uint(cnodes.x) & visibility))
#endif
{
mask |= 1;
}
}
if (bvh_unaligned_node_intersect_child(kg, P, dir, tmin, tmax, node_addr, 1, &dist[1])) {
#ifdef __VISIBILITY_FLAG__
if ((__float_as_uint(cnodes.y) & visibility))
#endif
{
mask |= 2;
}
}
return mask;
}
ccl_device_forceinline int bvh_node_intersect(KernelGlobals kg,
const float3 P,
const float3 dir,
const float3 idir,
const float tmin,
const float tmax,
const int node_addr,
const uint visibility,
float dist[2])
{
float4 node = kernel_data_fetch(bvh_nodes, node_addr);
if (__float_as_uint(node.x) & PATH_RAY_NODE_UNALIGNED) {
return bvh_unaligned_node_intersect(kg, P, dir, idir, tmin, tmax, node_addr, visibility, dist);
}
else {
return bvh_aligned_node_intersect(kg, P, idir, tmin, tmax, node_addr, visibility, dist);
}
}
|
