cuda-samples/Samples/nbody_screen/render_particles.cpp

375 lines
11 KiB
C++
Raw Normal View History

2021-10-21 19:04:49 +08:00
/* Copyright (c) 2021, NVIDIA CORPORATION. All rights reserved.
*
* 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.
*/
#include "render_particles.h"
#include <cuda_runtime.h>
#include <cuda_gl_interop.h>
#include <helper_cuda.h>
#include <math.h>
#include <assert.h>
void mat_identity(matrix4 m) {
m[0][1] = m[0][2] = m[0][3] = m[1][0] = m[1][2] = m[1][3] = m[2][0] =
m[2][1] = m[2][3] = m[3][0] = m[3][1] = m[3][2] = 0.0f;
m[0][0] = m[1][1] = m[2][2] = m[3][3] = 1.0f;
}
void mat_multiply(matrix4 m0, matrix4 m1) {
float m[4];
for (int r = 0; r < 4; r++) {
m[0] = m[1] = m[2] = m[3] = 0.0f;
for (int c = 0; c < 4; c++) {
for (int i = 0; i < 4; i++) {
m[c] += m0[i][r] * m1[c][i];
}
}
for (int c = 0; c < 4; c++) {
m0[c][r] = m[c];
}
}
}
void mat_translate(matrix4 m, vector3 v) {
matrix4 m2;
m2[0][0] = m2[1][1] = m2[2][2] = m2[3][3] = 1.0f;
m2[0][1] = m2[0][2] = m2[0][3] = m2[1][0] = m2[1][2] = m2[1][3] = m2[2][0] =
m2[2][1] = m2[2][3] = 0.0f;
m2[3][0] = v[0];
m2[3][1] = v[1];
m2[3][2] = v[2];
mat_multiply(m, m2);
}
void mat_perspective(matrix4 m, GLfloat fovy, GLfloat aspect, GLfloat znear,
GLfloat zfar) {
matrix4 m2;
m2[1][0] = m2[2][0] = m2[3][0] = m2[0][1] = m2[2][1] = m2[3][1] = m2[0][2] =
m2[1][2] = m2[0][3] = m2[1][3] = m2[3][3] = 0.0f;
m2[2][3] = -1.0f;
float f = 1 / tan((fovy * M_PI / 180) / 2);
m2[0][0] = f / aspect;
m2[1][1] = f;
m2[2][2] = ((znear + zfar) / (znear - zfar));
m2[3][2] = ((2 * znear * zfar) / (znear - zfar));
mat_multiply(m, m2);
}
ParticleRenderer::ParticleRenderer(unsigned int windowWidth,
unsigned int windowHeight)
: m_pos(0),
m_numParticles(0),
m_pointSize(1.0f),
m_spriteSize(2.0f),
m_vertexShader(0),
m_vertexShaderPoints(0),
m_fragmentShader(0),
m_programPoints(0),
m_programSprites(0),
m_texture(0),
m_pbo(0),
m_vboColor(0),
m_windowWidth(windowWidth),
m_windowHeight(windowHeight),
m_bFp64Positions(false) {
m_camera[0] = 0;
m_camera[1] = 0;
m_camera[2] = 0;
_initGL();
}
ParticleRenderer::~ParticleRenderer() { m_pos = 0; }
void ParticleRenderer::resetPBO() { glDeleteBuffers(1, (GLuint *)&m_pbo); }
void ParticleRenderer::setPositions(float *pos, int numParticles) {
m_pos = pos;
m_numParticles = numParticles;
if (!m_pbo) {
glGenBuffers(1, (GLuint *)&m_pbo);
}
glBindBuffer(GL_ARRAY_BUFFER, m_pbo);
glBufferData(GL_ARRAY_BUFFER, numParticles * 4 * sizeof(float), pos,
GL_STATIC_DRAW);
glBindBuffer(GL_ARRAY_BUFFER, 0);
checkGLErrors("Setting particle float position");
}
void ParticleRenderer::setPositions(double *pos, int numParticles) {
m_bFp64Positions = true;
m_pos_fp64 = pos;
m_numParticles = numParticles;
if (!m_pbo) {
glGenBuffers(1, (GLuint *)&m_pbo);
}
glBindBuffer(GL_ARRAY_BUFFER, m_pbo);
glBufferData(GL_ARRAY_BUFFER, numParticles * 4 * sizeof(double), pos,
GL_STATIC_DRAW);
glBindBuffer(GL_ARRAY_BUFFER, 0);
checkGLErrors("Setting particle double position");
}
void ParticleRenderer::setColors(float *color, int numParticles) {
glBindBuffer(GL_ARRAY_BUFFER, m_vboColor);
glBufferData(GL_ARRAY_BUFFER, numParticles * 4 * sizeof(float), color,
GL_STATIC_DRAW);
glBindBuffer(GL_ARRAY_BUFFER, 0);
}
void ParticleRenderer::setBaseColor(float color[4]) {
for (int i = 0; i < 4; i++) m_baseColor[i] = color[i];
}
void ParticleRenderer::setPBO(unsigned int pbo, int numParticles, bool fp64) {
m_pbo = pbo;
m_numParticles = numParticles;
if (fp64) m_bFp64Positions = true;
}
void ParticleRenderer::display() {
glEnable(GL_BLEND);
glBlendFunc(GL_SRC_ALPHA, GL_ONE);
glDepthMask(GL_FALSE);
glUseProgram(m_programSprites);
// Set modelview and projection matrices
GLint h_ModelViewMatrix = glGetUniformLocation(m_programSprites, "modelview");
GLint h_ProjectionMatrix =
glGetUniformLocation(m_programSprites, "projection");
matrix4 modelview;
matrix4 projection;
mat_identity(modelview);
mat_identity(projection);
mat_translate(modelview, m_camera);
mat_perspective(projection, 60, (float)m_windowWidth / (float)m_windowHeight,
0.1, 1000.0);
glUniformMatrix4fv(h_ModelViewMatrix, 1, GL_FALSE, (GLfloat *)modelview);
glUniformMatrix4fv(h_ProjectionMatrix, 1, GL_FALSE, (GLfloat *)projection);
// Set point size
GLint h_PointSize = glGetUniformLocation(m_programSprites, "size");
glUniform1f(h_PointSize, m_spriteSize);
// Set base and secondary colors
GLint h_BaseColor = glGetUniformLocation(m_programSprites, "baseColor");
GLint h_SecondaryColor =
glGetUniformLocation(m_programSprites, "secondaryColor");
glUniform4f(h_BaseColor, 1.0, 1.0, 1.0, 1.0);
glUniform4f(h_SecondaryColor, m_baseColor[0], m_baseColor[1], m_baseColor[2],
m_baseColor[3]);
// Set position coords
GLint h_position = glGetAttribLocation(m_programSprites, "a_position");
glBindBuffer(GL_ARRAY_BUFFER, m_pbo);
glEnableVertexAttribArray(h_position);
glVertexAttribPointer(h_position, 4, GL_FLOAT, GL_FALSE, 0, 0);
GLuint texLoc = glGetUniformLocation(m_programSprites, "splatTexture");
glUniform1i(texLoc, 0);
glActiveTexture(GL_TEXTURE0);
glBindTexture(GL_TEXTURE_2D, m_texture);
glDrawArrays(GL_POINTS, 0, m_numParticles);
glDisableVertexAttribArray(h_position);
glUseProgram(0);
glDisable(GL_BLEND);
glDepthMask(GL_TRUE);
}
const char vertexShader[] = {
"attribute vec4 a_position;"
"uniform mat4 projection;"
"uniform mat4 modelview;"
"uniform float size;"
"void main()"
"{"
"float pointSize = 500.0 * size;"
"vec4 vert = a_position;"
"vert.w = 1.0;"
"vec3 pos_eye = vec3(modelview * vert);"
"gl_PointSize = max(1.0, pointSize / (1.0 - pos_eye.z));"
"gl_Position = projection * modelview * a_position;"
"}"};
const char fragmentShader[] = {
"uniform sampler2D splatTexture;"
"uniform lowp vec4 baseColor;"
"uniform lowp vec4 secondaryColor;"
"void main()"
"{"
"lowp vec4 textureColor = (0.6 + 0.4 * baseColor) * "
"texture2D(splatTexture, gl_PointCoord);"
"gl_FragColor = textureColor * secondaryColor;"
"}"};
// Checks if the shader is compiled.
static int CheckCompiled(GLuint shader) {
GLint isCompiled = 0;
glGetShaderiv(shader, GL_COMPILE_STATUS, &isCompiled);
if (!isCompiled) {
GLint infoLen = 0;
glGetShaderiv(shader, GL_INFO_LOG_LENGTH, &infoLen);
if (infoLen > 1) {
char *infoLog = (char *)malloc(sizeof(char) * infoLen);
glGetShaderInfoLog(shader, infoLen, NULL, infoLog);
printf("Error compiling program:\n%s\n", infoLog);
free(infoLog);
}
return 0;
}
return 1;
}
void ParticleRenderer::_initGL() {
m_vertexShader = glCreateShader(GL_VERTEX_SHADER);
m_fragmentShader = glCreateShader(GL_FRAGMENT_SHADER);
const char *v = vertexShader;
const char *f = fragmentShader;
glShaderSource(m_vertexShader, 1, &v, 0);
glShaderSource(m_fragmentShader, 1, &f, 0);
checkGLErrors("Shader Source");
glCompileShader(m_vertexShader);
glCompileShader(m_fragmentShader);
if (!CheckCompiled(m_vertexShader) || !CheckCompiled(m_fragmentShader)) {
printf("A shader failed to compile.\n");
exit(1);
}
m_programSprites = glCreateProgram();
checkGLErrors("create program");
glAttachShader(m_programSprites, m_vertexShader);
glAttachShader(m_programSprites, m_fragmentShader);
checkGLErrors("attaching shaders");
glLinkProgram(m_programSprites);
checkGLErrors("linking program");
EGLint linked;
glGetProgramiv(m_programSprites, GL_LINK_STATUS, &linked);
if (!linked) {
printf("A shader failed to link.\n");
exit(1);
}
_createTexture(32);
glGenBuffers(1, (GLuint *)&m_vboColor);
glBindBuffer(GL_ARRAY_BUFFER, m_vboColor);
glBufferData(GL_ARRAY_BUFFER, m_numParticles * 4 * sizeof(float), 0,
GL_STATIC_DRAW);
glBindBuffer(GL_ARRAY_BUFFER, 0);
}
//------------------------------------------------------------------------------
// Function : EvalHermite
// Description :
//------------------------------------------------------------------------------
/**
* EvalHermite(float pA, float pB, float vA, float vB, float u)
* @brief Evaluates Hermite basis functions for the specified coefficients.
*/
inline float evalHermite(float pA, float pB, float vA, float vB, float u) {
float u2 = (u * u), u3 = u2 * u;
float B0 = 2 * u3 - 3 * u2 + 1;
float B1 = -2 * u3 + 3 * u2;
float B2 = u3 - 2 * u2 + u;
float B3 = u3 - u;
return (B0 * pA + B1 * pB + B2 * vA + B3 * vB);
}
unsigned char *createGaussianMap(int N) {
float *M = new float[2 * N * N];
unsigned char *B = new unsigned char[4 * N * N];
float X, Y, Y2, Dist;
float Incr = 2.0f / N;
int i = 0;
int j = 0;
Y = -1.0f;
// float mmax = 0;
for (int y = 0; y < N; y++, Y += Incr) {
Y2 = Y * Y;
X = -1.0f;
for (int x = 0; x < N; x++, X += Incr, i += 2, j += 4) {
Dist = (float)sqrtf(X * X + Y2);
if (Dist > 1) Dist = 1;
M[i + 1] = M[i] = evalHermite(1.0f, 0, 0, 0, Dist);
B[j + 3] = B[j + 2] = B[j + 1] = B[j] = (unsigned char)(M[i] * 255);
}
}
delete[] M;
return (B);
}
void ParticleRenderer::_createTexture(int resolution) {
unsigned char *data = createGaussianMap(resolution);
glGenTextures(1, (GLuint *)&m_texture);
glBindTexture(GL_TEXTURE_2D, m_texture);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER,
GL_LINEAR); //_MIPMAP_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, resolution, resolution, 0, GL_RGBA,
GL_UNSIGNED_BYTE, data);
}