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我已經創建了一個簡單的粒子模擬從這個source噴泉。我也想用C++類來實現它。所以，試圖把這個邏輯的上述部分放在這個source的類中（這是一個非常好的框架）。我只需要繼承這個類並重新定義我想要的功能。OpenGL示例粒子模擬不顯示粒子
我定義了display()的函數，其中我稱之爲DrawObjects()。 我遇到了以下問題：
- 我初始化粒子的數量低至50或100或500沒有任何可見的。
- 我想爲我的粒子加載紋理（
BMP）。由於某種原因，這是失敗的。我嘗試了相對和絕對路徑。然後嘗試加載RAW紋理（使用IrfanViewer），但沒有運氣。還嘗試刪除紋理代碼以使它們變得簡單OpenGL基元。再次沒有運氣。 - 我寫了一個簡單的
DrawAxis()函數，實際上需要畫青色顏色軸與紅色彩色的字符串。但是，灰色彩色原語顯示出來。我檢查了使用grayscale配置的代碼，但沒有這樣的事情。
注意：使用Windows VC++ 2010。代碼可以在NippyZip找到。
最少的代碼
Main.cpp的
#include "ParticleSimulation.h"
int main(int argc, char *argv[]) {
ParticleSimulation particleSimulation(50);
particleSimulation.InitParticles();
particleSimulation.setLookAt(80.0, 80.0, 80.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0);
particleSimulation.startFramework(argc, argv);
// **Note** No code below startFramework() will get executed
return 0;
}
GlutFramework.cpp
#include "GlutFramework.h"
namespace glutFramework {
// Set constants
const double GlutFramework::FRAME_TIME = 1.0/GlutFramework::FPS * 1000.0; // Milliseconds
GlutFramework *GlutFramework::instance = NULL;
GlutFramework::GlutFramework() {
elapsedTimeInSeconds = 0;
frameTimeElapsed = 0;
title = "GLUT Framework: Paul Solt 2010";
eyeVector = Vector<float>(0.0, 0.0, -10.0); // move the eye position back
position = 0.0f;
direction = 1.0/FRAME_TIME;
}
GlutFramework::~GlutFramework() {
}
void GlutFramework::startFramework(int argc, char *argv[]) {
setInstance(); // Sets the instance to self, used in the callback wrapper functions
// Initialize GLUT
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_RGBA | GLUT_DOUBLE | GLUT_DEPTH);
glutInitWindowPosition(WINDOW_X_POSITION, WINDOW_Y_POSITION);
glutInitWindowSize(WINDOW_WIDTH, WINDOW_HEIGHT);
glutCreateWindow(title.c_str());
// Function callbacks with wrapper functions
glutReshapeFunc(reshapeWrapper);
glutMouseFunc(mouseButtonPressWrapper);
glutMotionFunc(mouseMoveWrapper);
glutDisplayFunc(displayWrapper);
glutKeyboardFunc(keyboardDownWrapper);
glutKeyboardUpFunc(keyboardUpWrapper);
glutSpecialFunc(specialKeyboardDownWrapper);
glutSpecialUpFunc(specialKeyboardUpWrapper);
init(); // Initialize
glutIdleFunc(runWrapper); // The program run loop
glutMainLoop(); // Start the main GLUT thread
}
void GlutFramework::load() {
// Subclass and override this method
}
void GlutFramework::display(float dTime) {
// Subclass and override this method
static int frame = 0;
std::cout << "GlutFramework Display: Frame: " << frame << ", dt(sec): " << dTime << ", Position: " << position << std::endl;
++frame;
// DEMO: Create a teapot and move it back and forth on the x-axis
glTranslatef(position, 0.0f, 0.0f);
glutSolidTeapot(2.5);
if(position > 4 && direction > 0) {
direction = -1.0/FRAME_TIME;
} else if(position < -4 && direction < 0) {
direction = 1.0/FRAME_TIME;
}
position += direction;
}
void GlutFramework::reshape(int width, int height) {
glViewport(0,0,(GLsizei)width,(GLsizei)height);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluOrtho2D(0.0, (GLdouble) width, 0.0, (GLdouble) height);
}
void GlutFramework::mouseButtonPress(int button, int state, int x, int y) {
printf("MouseButtonPress: x: %d y: %d\n", x, y);
}
void GlutFramework::mouseMove(int x, int y) {
printf("MouseMove: x: %d y: %d\n", x, y);
}
void GlutFramework::keyboardDown(unsigned char key, int x, int y)
{
// Subclass and override this method
printf("KeyboardDown: %c = %d\n", key, (int)key);
if (key==27) { //27 =- ESC key
exit (0);
}
keyStates.keyDown((int)key);
}
void GlutFramework::keyboardUp(unsigned char key, int x, int y)
{
// Subclass and override this method
printf("KeyboardUp: %c \n", key);
keyStates.keyUp((int)key);
}
void GlutFramework::specialKeyboardDown(int key, int x, int y)
{
// Subclass and override this method
printf("SpecialKeyboardDown: %d\n", key);
}
void GlutFramework::specialKeyboardUp(int key, int x, int y)
{
// Subclass and override this method
printf("SpecialKeyboardUp: %d \n", key);
}
// ******************************
// ** Graphics helper routines **
// ******************************
// Initialize the projection/view matricies.
void GlutFramework::setDisplayMatricies() {
/* Setup the projection and model view matricies */
int width = glutGet(GLUT_WINDOW_WIDTH);
int height = glutGet(GLUT_WINDOW_HEIGHT);
float aspectRatio = width/height;
glViewport(0, 0, width, height);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluPerspective(60, aspectRatio, 1, 500.0);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
gluLookAt(eyeVector.x, eyeVector.y, eyeVector.z,
centerVector.x, centerVector.y, centerVector.z,
upVector.x, upVector.y, upVector.z);
}
void GlutFramework::setupLights() {
GLfloat light1_position[] = { 0.0, 1.0, 1.0, 0.0 };
GLfloat white_light[] = { 1.0, 1.0, 1.0, 1.0 };
GLfloat lmodel_ambient[] = { 0.4, 0.4, 0.4, 1.0 };
GLfloat ambient_light[] = { 0.8, 0.8, 0.8, 1.0 };
glLightfv(GL_LIGHT0, GL_POSITION, light1_position);
glLightfv(GL_LIGHT0, GL_AMBIENT, ambient_light);
glLightfv(GL_LIGHT0, GL_DIFFUSE, white_light);
glLightfv(GL_LIGHT0, GL_SPECULAR, white_light);
glLightModelfv(GL_LIGHT_MODEL_AMBIENT, lmodel_ambient);
}
void GlutFramework::setLookAt(float eyeX, float eyeY, float eyeZ,
float centerX, float centerY, float centerZ, float upX, float upY, float upZ) {
eyeVector = Vector<float>(eyeX, eyeY, eyeZ);
centerVector = Vector<float>(centerX, centerY, centerZ);
upVector = Vector<float>(upX, upY, upZ);
}
Vector<float> GlutFramework::getEyeVector() const {
return eyeVector;
}
Vector<float> GlutFramework::getCenterVector() const {
return centerVector;
}
Vector<float> GlutFramework::getUpVector() const {
return upVector;
}
void GlutFramework::setTitle(std::string theTitle) {
title = theTitle;
}
// **************************
// ** GLUT Setup functions **
// **************************
void GlutFramework::init() {
glClearColor(0.0, 0.0, 0.0, 1.0);
glEnable(GL_LIGHTING);
glEnable(GL_LIGHT0);
glShadeModel(GL_SMOOTH);
glEnable(GL_DEPTH_TEST);
load();
}
void GlutFramework::setInstance() {
//std::cout << "GlutFramework::setInstance()" << std::endl;
instance = this;
}
void GlutFramework::run() {
if(frameRateTimer.isStopped()) { // The initial frame has the timer stopped, start it once
frameRateTimer.start();
}
frameRateTimer.stop(); // stop the timer and calculate time since last frame
double milliseconds = frameRateTimer.getElapsedMilliseconds();
frameTimeElapsed += milliseconds;
if(frameTimeElapsed >= FRAME_TIME) { // If the time exceeds a certain "frame rate" then show the next frame
glutPostRedisplay();
frameTimeElapsed -= FRAME_TIME; // remove a "frame" and start counting up again
}
frameRateTimer.start(); // start the timer
}
void GlutFramework::displayFramework() {
if(displayTimer.isStopped()) { // Start the timer on the initial frame
displayTimer.start();
}
glClearColor(0.0, 0.0, 0.0, 1.0);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); // Clear once
displayTimer.stop(); // Stop the timer and get the elapsed time in seconds
elapsedTimeInSeconds = displayTimer.getElapsedSeconds(); // seconds
setupLights();
setDisplayMatricies();
display(elapsedTimeInSeconds);
glutSwapBuffers();
displayTimer.start(); // reset the timer to calculate the time for the next frame
}
// ******************************************************************
// ** Static functions which are passed to Glut function callbacks **
// ******************************************************************
void GlutFramework::displayWrapper() {
instance->displayFramework();
}
void GlutFramework::reshapeWrapper(int width, int height) {
instance->reshape(width, height);
}
void GlutFramework::runWrapper() {
instance->run();
}
void GlutFramework::mouseButtonPressWrapper(int button, int state, int x, int y) {
instance->mouseButtonPress(button, state, x, y);
}
void GlutFramework::mouseMoveWrapper(int x, int y) {
instance->mouseMove(x, y);
}
void GlutFramework::keyboardDownWrapper(unsigned char key, int x, int y) {
instance->keyboardDown(key,x,y);
}
void GlutFramework::keyboardUpWrapper(unsigned char key, int x, int y) {
instance->keyboardUp(key,x,y);
}
void GlutFramework::specialKeyboardDownWrapper(int key, int x, int y) {
instance->specialKeyboardDown(key,x,y);
}
void GlutFramework::specialKeyboardUpWrapper(int key, int x, int y) {
instance->specialKeyboardUp(key,x,y);
}
} // namespace
ParticleSimulation.h
#include "preheader.h"
#include "Particle.h"
#include "GlutFramework.h"
#ifndef ___PARTICLESIMULATION_H___
#define ___PARTICLESIMULATION_H___
using namespace glutFramework;
#ifndef ABS_IMAGE_LOCATION
#define ABS_IMAGE_LOCATION "E:/IIIT B/College/Sem 3/CG/GraphicAssignment3/images/particle.bmp"
#endif
class ParticleSimulation : virtual public GlutFramework{
private:
GLuint numParticles; // total number of particles in the system
Particle *particles;
GLuint textureParticle;
//static GLint textureCount;
//functions
void AllocateObjects(void);
void DeAllocateObjects(void);
public:
ParticleSimulation(void);
ParticleSimulation(GLuint numParticles);
~ParticleSimulation(void);
void InitParticles(void);
void EvolveParticle(void);
void DisplayObjects(void);
void LoadTextureRAW(const char * filename, int wrap);
void LoadTextureBMP(const char * filename, int wrap);
void FreeTexture(void);
void DrawAxis();
void RenderBitmapString(GLfloat x, GLfloat y, GLfloat z, void *font, char *string);
//virtual functions
void display(float dTime);
};
#endif //___PARTICLESIMULATION_H___
ParticleSimulation.cpp
#include "ParticleSimulation.h"
using namespace std;
. . .
void ParticleSimulation::DisplayObjects(){
// rendering functions
glLoadIdentity();
//glRotatef(20.0, 1.0, 0.0, 0.0); // show scene from top front
//glBindTexture(GL_TEXTURE_2D, this->textureParticle); // choose particle texture
for (int i = 0; i <= this->numParticles; i++){
GLfloat xpos = 0.0f, ypos = 0.0f, zpos = 0.0f;
particles[i].getPosition(xpos, ypos, zpos);
if(ypos < 0.0)
particles[i].setLifeTime(0.0);
if(particles[i].getActiveStatus() && particles[i].getLifeTime() > 0.0) {
GLfloat red = 0.0f, green = 0.0f, blue = 0.0f;
particles[i].getColor(red, green, blue);
glColor3f(red, green, blue);
glBegin(GL_TRIANGLE_STRIP);
glVertex2f(0.0,1.0); glVertex3f(xpos + 0.002, ypos + 0.002, zpos + 0.0); // top right
glVertex2f(0.0,0.0); glVertex3f(xpos - 0.002, ypos + 0.002, zpos + 0.0); // top left
glVertex2f(1.0,1.0); glVertex3f(xpos + 0.002, ypos - 0.002, zpos + 0.0); // bottom right
glVertex2f(1.0,0.0); glVertex3f(xpos - 0.002, ypos - 0.002, zpos + 0.0); // bottom left
//glTexCoord2f(1.0,0.0); glVertex3f(xpos - 0.002, ypos - 0.002, zpos + 0.0); // bottom left
glEnd();
} else {
particles[i].CreateParticle();
}
}
EvolveParticle();
}
void ParticleSimulation::EvolveParticle()
{
for(int i = 0; i <= this->numParticles; i++){ // evolve the particle parameters
GLfloat xpos = 0.0f, ypos = 0.0f, zpos = 0.0f;
GLfloat green = 0.0f, red = 0.0f, blue = 0.0f;
GLfloat xVel = 0.0f, yVel = 0.0f, zVel = 0.0f;
particles[i].setLifeTime(particles[i].getLifeTime() - particles[i].getDecay());
particles[i].getPosition(xpos, ypos, zpos);
particles[i].getSpeed(xVel, yVel, zVel);
particles[i].getPosition(xpos += xVel, ypos += yVel, zpos += zVel);
particles[i].getSpeed(xVel, yVel -= 0.00007, zVel);
}
}
// Texture ///////////////////////////////////////////////////////////
// load a 256x256 RGB .RAW file as a texture
void ParticleSimulation::LoadTextureBMP(const char * filename, int wrap)
{
int width = 0, height = 0;
BYTE *data = NULL;
FILE *file = NULL;
// open texture data
file = fopen(filename, "rb");
if (file == NULL) {
cout << "\nFile could not be opened." << endl;
return;
}
// allocate buffer
width = 256;
height = 256;
data = (BYTE *) malloc(width * height * 3);
// read texture data
fread(data, width * height * 3, 1, file);
fclose(file);
// allocate a texture name
this->textureParticle = 0;
glGenTextures(1, &this->textureParticle);
// select our current texture
glBindTexture(GL_TEXTURE_2D, this->textureParticle);
// select modulate to mix texture with color for shading
glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
// when texture area is small, bilinear filter the closest MIP map
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER,
GL_LINEAR_MIPMAP_NEAREST);
// when texture area is large, bilinear filter the first MIP map
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
// if wrap is true, the texture wraps over at the edges (repeat)
// ... false, the texture ends at the edges (clamp)
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S,
wrap ? GL_REPEAT : GL_CLAMP);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T,
wrap ? GL_REPEAT : GL_CLAMP);
// build our texture MIP maps
gluBuild2DMipmaps(GL_TEXTURE_2D, 3, width,
height, GL_RGB, GL_UNSIGNED_BYTE, data);
// free buffer
free(data);
return;
}
void ParticleSimulation::FreeTexture(void)
{
glDeleteTextures(1, &this->textureParticle);
}
void ParticleSimulation::DrawAxis() {
char s1[10];
glPushMatrix();
glColor3f(1.0f, 0.0f, 0.0f);
sprintf(s1, "X-axis");
RenderBitmapString(50.0f, 0.0f, 0.0f, GLUT_BITMAP_HELVETICA_12, s1);
sprintf(s1, "Y-axis");
RenderBitmapString(0.0f, 50.0f, 0.0f, GLUT_BITMAP_HELVETICA_12, s1);
sprintf(s1, "Z-axis");
RenderBitmapString(0.0f, 0.0f, 50.0f, GLUT_BITMAP_HELVETICA_12, s1);
sprintf(s1, "Origin");
RenderBitmapString(0.0f, 0.0f, 0.0f, GLUT_BITMAP_HELVETICA_12, s1);
glPointSize(4.0f);
glColor3f(0.0f, 1.0f, 1.0f);
glBegin(GL_LINE_STRIP);
glVertex3f(0.0f, 0.0f, 0.0f);
glVertex3f(0.0f, 50.0f, 0.0f);
glEnd();
glBegin(GL_LINE_STRIP);
glVertex3f(0.0f, 0.0f, 0.0f);
glVertex3f(50.0f, 0.0f, 0.0f);
glEnd();
glBegin(GL_LINE_STRIP);
glVertex3f(0.0f, 0.0f, 0.0f);
glVertex3f(0.0f, 0.0f, 50.0f);
glEnd();
glPopMatrix();
}
void ParticleSimulation::display(float dTime)
{
static int frame = 0;
//cout << "GlutFramework Display: Frame: " << frame << ", dt(sec): " << dTime << ", Position: " << position << endl;
++frame;
//cout << "Calling the DisplayObject Function" << endl;
//glTranslatef(0.0f, 0.0f, 0.0f);
//glutSolidTeapot(2.5);
DrawAxis(); //Aditya: Working with grayscale though
DisplayObjects(); //Aditya: Nothing is drawn
}
發佈一個完整的*最小*程序來演示問題。 – genpfault
這裏..請找到代碼片段@genpfault – Aditya369