mirror of
https://github.com/NVIDIA/cuda-samples.git
synced 2025-07-02 04:41:59 +08:00
495 lines
14 KiB
C++
495 lines
14 KiB
C++
/*
|
|
* Copyright 1993-2015 NVIDIA Corporation. All rights reserved.
|
|
*
|
|
* Please refer to the NVIDIA end user license agreement (EULA) associated
|
|
* with this source code for terms and conditions that govern your use of
|
|
* this software. Any use, reproduction, disclosure, or distribution of
|
|
* this software and related documentation outside the terms of the EULA
|
|
* is strictly prohibited.
|
|
*
|
|
*/
|
|
|
|
// OpenGL Graphics includes
|
|
#define HELPERGL_EXTERN_GL_FUNC_IMPLEMENTATION
|
|
#include "particleSystem.h"
|
|
|
|
#include <algorithm>
|
|
#include <assert.h>
|
|
#include <cstdio>
|
|
#include <cstdlib>
|
|
#include <cuda_runtime.h>
|
|
#include <helper_cuda.h>
|
|
#include <helper_functions.h>
|
|
#include <helper_gl.h>
|
|
#include <math.h>
|
|
#include <memory.h>
|
|
|
|
#include "particleSystem.cuh"
|
|
#include "particles_kernel.cuh"
|
|
|
|
#ifndef CUDART_PI_F
|
|
#define CUDART_PI_F 3.141592654f
|
|
#endif
|
|
|
|
ParticleSystem::ParticleSystem(uint numParticles, uint3 gridSize, bool bUseOpenGL)
|
|
: m_bInitialized(false)
|
|
, m_bUseOpenGL(bUseOpenGL)
|
|
, m_numParticles(numParticles)
|
|
, m_hPos(0)
|
|
, m_hVel(0)
|
|
, m_dPos(0)
|
|
, m_dVel(0)
|
|
, m_gridSize(gridSize)
|
|
, m_timer(NULL)
|
|
, m_solverIterations(1)
|
|
{
|
|
m_numGridCells = m_gridSize.x * m_gridSize.y * m_gridSize.z;
|
|
// float3 worldSize = make_float3(2.0f, 2.0f, 2.0f);
|
|
|
|
m_gridSortBits = 18; // increase this for larger grids
|
|
|
|
// set simulation parameters
|
|
m_params.gridSize = m_gridSize;
|
|
m_params.numCells = m_numGridCells;
|
|
m_params.numBodies = m_numParticles;
|
|
|
|
m_params.particleRadius = 1.0f / 64.0f;
|
|
m_params.colliderPos = make_float3(-1.2f, -0.8f, 0.8f);
|
|
m_params.colliderRadius = 0.2f;
|
|
|
|
m_params.worldOrigin = make_float3(-1.0f, -1.0f, -1.0f);
|
|
// m_params.cellSize = make_float3(worldSize.x / m_gridSize.x, worldSize.y / m_gridSize.y, worldSize.z /
|
|
// m_gridSize.z);
|
|
float cellSize = m_params.particleRadius * 2.0f; // cell size equal to particle diameter
|
|
m_params.cellSize = make_float3(cellSize, cellSize, cellSize);
|
|
|
|
m_params.spring = 0.5f;
|
|
m_params.damping = 0.02f;
|
|
m_params.shear = 0.1f;
|
|
m_params.attraction = 0.0f;
|
|
m_params.boundaryDamping = -0.5f;
|
|
|
|
m_params.gravity = make_float3(0.0f, -0.0003f, 0.0f);
|
|
m_params.globalDamping = 1.0f;
|
|
|
|
_initialize(numParticles);
|
|
}
|
|
|
|
ParticleSystem::~ParticleSystem()
|
|
{
|
|
_finalize();
|
|
m_numParticles = 0;
|
|
}
|
|
|
|
uint ParticleSystem::createVBO(uint size)
|
|
{
|
|
GLuint vbo;
|
|
glGenBuffers(1, &vbo);
|
|
glBindBuffer(GL_ARRAY_BUFFER, vbo);
|
|
glBufferData(GL_ARRAY_BUFFER, size, 0, GL_DYNAMIC_DRAW);
|
|
glBindBuffer(GL_ARRAY_BUFFER, 0);
|
|
return vbo;
|
|
}
|
|
|
|
inline float lerp(float a, float b, float t) { return a + t * (b - a); }
|
|
|
|
// create a color ramp
|
|
void colorRamp(float t, float *r)
|
|
{
|
|
const int ncolors = 7;
|
|
float c[ncolors][3] = {
|
|
{
|
|
1.0,
|
|
0.0,
|
|
0.0,
|
|
},
|
|
{
|
|
1.0,
|
|
0.5,
|
|
0.0,
|
|
},
|
|
{
|
|
1.0,
|
|
1.0,
|
|
0.0,
|
|
},
|
|
{
|
|
0.0,
|
|
1.0,
|
|
0.0,
|
|
},
|
|
{
|
|
0.0,
|
|
1.0,
|
|
1.0,
|
|
},
|
|
{
|
|
0.0,
|
|
0.0,
|
|
1.0,
|
|
},
|
|
{
|
|
1.0,
|
|
0.0,
|
|
1.0,
|
|
},
|
|
};
|
|
t = t * (ncolors - 1);
|
|
int i = (int)t;
|
|
float u = t - floorf(t);
|
|
r[0] = lerp(c[i][0], c[i + 1][0], u);
|
|
r[1] = lerp(c[i][1], c[i + 1][1], u);
|
|
r[2] = lerp(c[i][2], c[i + 1][2], u);
|
|
}
|
|
|
|
void ParticleSystem::_initialize(int numParticles)
|
|
{
|
|
assert(!m_bInitialized);
|
|
|
|
m_numParticles = numParticles;
|
|
|
|
// allocate host storage
|
|
m_hPos = new float[m_numParticles * 4];
|
|
m_hVel = new float[m_numParticles * 4];
|
|
memset(m_hPos, 0, m_numParticles * 4 * sizeof(float));
|
|
memset(m_hVel, 0, m_numParticles * 4 * sizeof(float));
|
|
|
|
m_hCellStart = new uint[m_numGridCells];
|
|
memset(m_hCellStart, 0, m_numGridCells * sizeof(uint));
|
|
|
|
m_hCellEnd = new uint[m_numGridCells];
|
|
memset(m_hCellEnd, 0, m_numGridCells * sizeof(uint));
|
|
|
|
// allocate GPU data
|
|
unsigned int memSize = sizeof(float) * 4 * m_numParticles;
|
|
|
|
if (m_bUseOpenGL) {
|
|
m_posVbo = createVBO(memSize);
|
|
registerGLBufferObject(m_posVbo, &m_cuda_posvbo_resource);
|
|
}
|
|
else {
|
|
checkCudaErrors(cudaMalloc((void **)&m_cudaPosVBO, memSize));
|
|
}
|
|
|
|
allocateArray((void **)&m_dVel, memSize);
|
|
|
|
allocateArray((void **)&m_dSortedPos, memSize);
|
|
allocateArray((void **)&m_dSortedVel, memSize);
|
|
|
|
allocateArray((void **)&m_dGridParticleHash, m_numParticles * sizeof(uint));
|
|
allocateArray((void **)&m_dGridParticleIndex, m_numParticles * sizeof(uint));
|
|
|
|
allocateArray((void **)&m_dCellStart, m_numGridCells * sizeof(uint));
|
|
allocateArray((void **)&m_dCellEnd, m_numGridCells * sizeof(uint));
|
|
|
|
if (m_bUseOpenGL) {
|
|
m_colorVBO = createVBO(m_numParticles * 4 * sizeof(float));
|
|
registerGLBufferObject(m_colorVBO, &m_cuda_colorvbo_resource);
|
|
|
|
// fill color buffer
|
|
glBindBuffer(GL_ARRAY_BUFFER, m_colorVBO);
|
|
float *data = (float *)glMapBuffer(GL_ARRAY_BUFFER, GL_WRITE_ONLY);
|
|
float *ptr = data;
|
|
|
|
for (uint i = 0; i < m_numParticles; i++) {
|
|
float t = i / (float)m_numParticles;
|
|
#if 0
|
|
*ptr++ = rand() / (float) RAND_MAX;
|
|
*ptr++ = rand() / (float) RAND_MAX;
|
|
*ptr++ = rand() / (float) RAND_MAX;
|
|
#else
|
|
colorRamp(t, ptr);
|
|
ptr += 3;
|
|
#endif
|
|
*ptr++ = 1.0f;
|
|
}
|
|
|
|
glUnmapBuffer(GL_ARRAY_BUFFER);
|
|
}
|
|
else {
|
|
checkCudaErrors(cudaMalloc((void **)&m_cudaColorVBO, sizeof(float) * numParticles * 4));
|
|
}
|
|
|
|
sdkCreateTimer(&m_timer);
|
|
|
|
setParameters(&m_params);
|
|
|
|
m_bInitialized = true;
|
|
}
|
|
|
|
void ParticleSystem::_finalize()
|
|
{
|
|
assert(m_bInitialized);
|
|
|
|
delete[] m_hPos;
|
|
delete[] m_hVel;
|
|
delete[] m_hCellStart;
|
|
delete[] m_hCellEnd;
|
|
|
|
freeArray(m_dVel);
|
|
freeArray(m_dSortedPos);
|
|
freeArray(m_dSortedVel);
|
|
|
|
freeArray(m_dGridParticleHash);
|
|
freeArray(m_dGridParticleIndex);
|
|
freeArray(m_dCellStart);
|
|
freeArray(m_dCellEnd);
|
|
|
|
if (m_bUseOpenGL) {
|
|
unregisterGLBufferObject(m_cuda_colorvbo_resource);
|
|
unregisterGLBufferObject(m_cuda_posvbo_resource);
|
|
glDeleteBuffers(1, (const GLuint *)&m_posVbo);
|
|
glDeleteBuffers(1, (const GLuint *)&m_colorVBO);
|
|
}
|
|
else {
|
|
checkCudaErrors(cudaFree(m_cudaPosVBO));
|
|
checkCudaErrors(cudaFree(m_cudaColorVBO));
|
|
}
|
|
}
|
|
|
|
// step the simulation
|
|
void ParticleSystem::update(float deltaTime)
|
|
{
|
|
assert(m_bInitialized);
|
|
|
|
float *dPos;
|
|
|
|
if (m_bUseOpenGL) {
|
|
dPos = (float *)mapGLBufferObject(&m_cuda_posvbo_resource);
|
|
}
|
|
else {
|
|
dPos = (float *)m_cudaPosVBO;
|
|
}
|
|
|
|
// update constants
|
|
setParameters(&m_params);
|
|
|
|
// integrate
|
|
integrateSystem(dPos, m_dVel, deltaTime, m_numParticles);
|
|
|
|
// calculate grid hash
|
|
calcHash(m_dGridParticleHash, m_dGridParticleIndex, dPos, m_numParticles);
|
|
|
|
// sort particles based on hash
|
|
sortParticles(m_dGridParticleHash, m_dGridParticleIndex, m_numParticles);
|
|
|
|
// reorder particle arrays into sorted order and
|
|
// find start and end of each cell
|
|
reorderDataAndFindCellStart(m_dCellStart,
|
|
m_dCellEnd,
|
|
m_dSortedPos,
|
|
m_dSortedVel,
|
|
m_dGridParticleHash,
|
|
m_dGridParticleIndex,
|
|
dPos,
|
|
m_dVel,
|
|
m_numParticles,
|
|
m_numGridCells);
|
|
|
|
// process collisions
|
|
collide(m_dVel,
|
|
m_dSortedPos,
|
|
m_dSortedVel,
|
|
m_dGridParticleIndex,
|
|
m_dCellStart,
|
|
m_dCellEnd,
|
|
m_numParticles,
|
|
m_numGridCells);
|
|
|
|
// note: do unmap at end here to avoid unnecessary graphics/CUDA context switch
|
|
if (m_bUseOpenGL) {
|
|
unmapGLBufferObject(m_cuda_posvbo_resource);
|
|
}
|
|
}
|
|
|
|
void ParticleSystem::dumpGrid()
|
|
{
|
|
// dump grid information
|
|
copyArrayFromDevice(m_hCellStart, m_dCellStart, 0, sizeof(uint) * m_numGridCells);
|
|
copyArrayFromDevice(m_hCellEnd, m_dCellEnd, 0, sizeof(uint) * m_numGridCells);
|
|
uint maxCellSize = 0;
|
|
|
|
for (uint i = 0; i < m_numGridCells; i++) {
|
|
if (m_hCellStart[i] != 0xffffffff) {
|
|
uint cellSize = m_hCellEnd[i] - m_hCellStart[i];
|
|
|
|
// printf("cell: %d, %d particles\n", i, cellSize);
|
|
if (cellSize > maxCellSize) {
|
|
maxCellSize = cellSize;
|
|
}
|
|
}
|
|
}
|
|
|
|
printf("maximum particles per cell = %d\n", maxCellSize);
|
|
}
|
|
|
|
void ParticleSystem::dumpParticles(uint start, uint count)
|
|
{
|
|
// debug
|
|
copyArrayFromDevice(m_hPos, 0, &m_cuda_posvbo_resource, sizeof(float) * 4 * count);
|
|
copyArrayFromDevice(m_hVel, m_dVel, 0, sizeof(float) * 4 * count);
|
|
|
|
for (uint i = start; i < start + count; i++) {
|
|
// printf("%d: ", i);
|
|
printf("pos: (%.4f, %.4f, %.4f, %.4f)\n",
|
|
m_hPos[i * 4 + 0],
|
|
m_hPos[i * 4 + 1],
|
|
m_hPos[i * 4 + 2],
|
|
m_hPos[i * 4 + 3]);
|
|
printf("vel: (%.4f, %.4f, %.4f, %.4f)\n",
|
|
m_hVel[i * 4 + 0],
|
|
m_hVel[i * 4 + 1],
|
|
m_hVel[i * 4 + 2],
|
|
m_hVel[i * 4 + 3]);
|
|
}
|
|
}
|
|
|
|
float *ParticleSystem::getArray(ParticleArray array)
|
|
{
|
|
assert(m_bInitialized);
|
|
|
|
float *hdata = 0;
|
|
float *ddata = 0;
|
|
struct cudaGraphicsResource *cuda_vbo_resource = 0;
|
|
|
|
switch (array) {
|
|
default:
|
|
case POSITION:
|
|
hdata = m_hPos;
|
|
ddata = m_dPos;
|
|
cuda_vbo_resource = m_cuda_posvbo_resource;
|
|
break;
|
|
|
|
case VELOCITY:
|
|
hdata = m_hVel;
|
|
ddata = m_dVel;
|
|
break;
|
|
}
|
|
|
|
copyArrayFromDevice(hdata, ddata, &cuda_vbo_resource, m_numParticles * 4 * sizeof(float));
|
|
return hdata;
|
|
}
|
|
|
|
void ParticleSystem::setArray(ParticleArray array, const float *data, int start, int count)
|
|
{
|
|
assert(m_bInitialized);
|
|
|
|
switch (array) {
|
|
default:
|
|
case POSITION: {
|
|
if (m_bUseOpenGL) {
|
|
unregisterGLBufferObject(m_cuda_posvbo_resource);
|
|
glBindBuffer(GL_ARRAY_BUFFER, m_posVbo);
|
|
glBufferSubData(GL_ARRAY_BUFFER, start * 4 * sizeof(float), count * 4 * sizeof(float), data);
|
|
glBindBuffer(GL_ARRAY_BUFFER, 0);
|
|
registerGLBufferObject(m_posVbo, &m_cuda_posvbo_resource);
|
|
}
|
|
else {
|
|
copyArrayToDevice(m_cudaPosVBO, data, start * 4 * sizeof(float), count * 4 * sizeof(float));
|
|
}
|
|
} break;
|
|
|
|
case VELOCITY:
|
|
copyArrayToDevice(m_dVel, data, start * 4 * sizeof(float), count * 4 * sizeof(float));
|
|
break;
|
|
}
|
|
}
|
|
|
|
inline float frand() { return rand() / (float)RAND_MAX; }
|
|
|
|
void ParticleSystem::initGrid(uint *size, float spacing, float jitter, uint numParticles)
|
|
{
|
|
srand(1973);
|
|
|
|
for (uint z = 0; z < size[2]; z++) {
|
|
for (uint y = 0; y < size[1]; y++) {
|
|
for (uint x = 0; x < size[0]; x++) {
|
|
uint i = (z * size[1] * size[0]) + (y * size[0]) + x;
|
|
|
|
if (i < numParticles) {
|
|
m_hPos[i * 4] = (spacing * x) + m_params.particleRadius - 1.0f + (frand() * 2.0f - 1.0f) * jitter;
|
|
m_hPos[i * 4 + 1] =
|
|
(spacing * y) + m_params.particleRadius - 1.0f + (frand() * 2.0f - 1.0f) * jitter;
|
|
m_hPos[i * 4 + 2] =
|
|
(spacing * z) + m_params.particleRadius - 1.0f + (frand() * 2.0f - 1.0f) * jitter;
|
|
m_hPos[i * 4 + 3] = 1.0f;
|
|
|
|
m_hVel[i * 4] = 0.0f;
|
|
m_hVel[i * 4 + 1] = 0.0f;
|
|
m_hVel[i * 4 + 2] = 0.0f;
|
|
m_hVel[i * 4 + 3] = 0.0f;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
void ParticleSystem::reset(ParticleConfig config)
|
|
{
|
|
switch (config) {
|
|
default:
|
|
case CONFIG_RANDOM: {
|
|
int p = 0, v = 0;
|
|
|
|
for (uint i = 0; i < m_numParticles; i++) {
|
|
float point[3];
|
|
point[0] = frand();
|
|
point[1] = frand();
|
|
point[2] = frand();
|
|
m_hPos[p++] = 2 * (point[0] - 0.5f);
|
|
m_hPos[p++] = 2 * (point[1] - 0.5f);
|
|
m_hPos[p++] = 2 * (point[2] - 0.5f);
|
|
m_hPos[p++] = 1.0f; // radius
|
|
m_hVel[v++] = 0.0f;
|
|
m_hVel[v++] = 0.0f;
|
|
m_hVel[v++] = 0.0f;
|
|
m_hVel[v++] = 0.0f;
|
|
}
|
|
} break;
|
|
|
|
case CONFIG_GRID: {
|
|
float jitter = m_params.particleRadius * 0.01f;
|
|
uint s = (int)ceilf(powf((float)m_numParticles, 1.0f / 3.0f));
|
|
uint gridSize[3];
|
|
gridSize[0] = gridSize[1] = gridSize[2] = s;
|
|
initGrid(gridSize, m_params.particleRadius * 2.0f, jitter, m_numParticles);
|
|
} break;
|
|
}
|
|
|
|
setArray(POSITION, m_hPos, 0, m_numParticles);
|
|
setArray(VELOCITY, m_hVel, 0, m_numParticles);
|
|
}
|
|
|
|
void ParticleSystem::addSphere(int start, float *pos, float *vel, int r, float spacing)
|
|
{
|
|
uint index = start;
|
|
|
|
for (int z = -r; z <= r; z++) {
|
|
for (int y = -r; y <= r; y++) {
|
|
for (int x = -r; x <= r; x++) {
|
|
float dx = x * spacing;
|
|
float dy = y * spacing;
|
|
float dz = z * spacing;
|
|
float l = sqrtf(dx * dx + dy * dy + dz * dz);
|
|
float jitter = m_params.particleRadius * 0.01f;
|
|
|
|
if ((l <= m_params.particleRadius * 2.0f * r) && (index < m_numParticles)) {
|
|
m_hPos[index * 4] = pos[0] + dx + (frand() * 2.0f - 1.0f) * jitter;
|
|
m_hPos[index * 4 + 1] = pos[1] + dy + (frand() * 2.0f - 1.0f) * jitter;
|
|
m_hPos[index * 4 + 2] = pos[2] + dz + (frand() * 2.0f - 1.0f) * jitter;
|
|
m_hPos[index * 4 + 3] = pos[3];
|
|
|
|
m_hVel[index * 4] = vel[0];
|
|
m_hVel[index * 4 + 1] = vel[1];
|
|
m_hVel[index * 4 + 2] = vel[2];
|
|
m_hVel[index * 4 + 3] = vel[3];
|
|
index++;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
setArray(POSITION, m_hPos, start, index);
|
|
setArray(VELOCITY, m_hVel, start, index);
|
|
}
|