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
|
//
// 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 NVIDIA CORPORATION 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 ``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.
//
// Copyright (c) 2008-2018 NVIDIA Corporation. All rights reserved.
#include "PxPhysics.h"
#include "PxVec4.h"
#include "PxVec3.h"
#include "PxVec2.h"
#include "cloth/PxClothTypes.h"
namespace physx
{
// interleaved format must match that used by RendererClothShape
struct Vertex
{
PxVec3 position;
PxVec3 normal;
};
namespace
{
__device__ inline void PxAtomicFloatAdd(float* dest, float x)
{
#if __CUDA_ARCH__ >= 200
atomicAdd(dest, x);
#else
union bits { float f; unsigned int i; };
bits oldVal, newVal;
do
{
// emulate atomic float add on 1.1 arch
oldVal.f = *dest;
newVal.f = oldVal.f + x;
}
while (atomicCAS((unsigned int*)dest, oldVal.i, newVal.i) != oldVal.i);
#endif
}
__device__ void PxAtomicVec3Add(PxVec3& dest, PxVec3 inc)
{
PxAtomicFloatAdd(&dest.x, inc.x);
PxAtomicFloatAdd(&dest.y, inc.y);
PxAtomicFloatAdd(&dest.z, inc.z);
}
}
extern "C" __global__ void computeSmoothNormals(
const PxClothParticle* particles,
const PxU16* indices,
Vertex* vertices,
PxU32 numTris,
PxU32 numParticles)
{
// zero old normals
for (PxU32 i=threadIdx.x; i < numParticles; i += blockDim.x)
vertices[i].normal = PxVec3(0.0f);
__syncthreads();
for (PxU32 i=threadIdx.x; i < numTris; i += blockDim.x)
{
PxU16 a = indices[i*3];
PxU16 b = indices[i*3+1];
PxU16 c = indices[i*3+2];
// calculate face normal
PxVec3 e1 = particles[b].pos-particles[a].pos;
PxVec3 e2 = particles[c].pos-particles[a].pos;
PxVec3 n = e2.cross(e1);
PxAtomicVec3Add(vertices[a].normal, n);
PxAtomicVec3Add(vertices[b].normal, n);
PxAtomicVec3Add(vertices[c].normal, n);
}
__syncthreads();
// update vertex buffer
for (PxU32 i=threadIdx.x; i < numParticles; i += blockDim.x)
{
vertices[i].position = particles[i].pos;
vertices[i].normal = vertices[i].normal.getNormalized();
}
}
}
|