OpenGL/Glut 无法在其上绘制 [
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【中文标题】OpenGL/Glut 无法在其上绘制 [【英文标题】：OpenGL/Glut Cant draw on it [ 【发布时间】：2014-04-22 08:23:47 【问题描述】：我正在开发一个非常简单的 OpenGL 项目。我正在尝试模拟牛顿的万有引力定律。此代码尚未完成。我已经创建了粒子，并添加了绘图功能。我对openGL真的很陌生，但我真的找不到为什么我只看到一个白色的窗口。我不能在上面画任何东西！不知道错在哪里。
#include <GLUT/GLUT.h>
#include <OpenGL/gl.h>
#include <stdlib.h> /* srand, rand */
#include <time.h> /* time */
#include <vector>
#include <stdio.h>
#include <iostream>
#include <math.h>
using namespace std;
GLfloat xRotated, yRotated, zRotated;
#define WIDTH 800
#define HEIGHT 1200
#define RAD 2000
// 6.67259(30)*10^-11 N(m/kg)^2
// mi escala sera la proporcion de 1 a 1 millón de toneladas.
#define GE 6.67259
void init(void)
glClearColor(0,1,0,0);
typedef struct particulas
float x,y,z; // se va a comenza
float factor;
void Drawparticulas();
particulas(float px,float py,float pz,float pfactor)
x=px;
y=py;
z=pz;
factor=pfactor;
;
void particulas::Drawparticulas()
// clear the drawing buffer.
glPushMatrix();
//glLoadIdentity();
glTranslatef(x,y,z);
//escala al tamaño pedido
glScalef(factor,factor,factor);
glBegin(GL_QUADS); // Draw The Cube Using quads
glColor3f(0.0f,1.0f,0.0f); // Color Blue
glVertex3f( 1.0f, 1.0f,-1.0f); // Top Right Of The Quad (Top)
glVertex3f(-1.0f, 1.0f,-1.0f); // Top Left Of The Quad (Top)
glVertex3f(-1.0f, 1.0f, 1.0f); // Bottom Left Of The Quad (Top)
glVertex3f( 1.0f, 1.0f, 1.0f); // Bottom Right Of The Quad (Top)
glColor3f(1.0f,0.5f,0.0f); // Color Orange
glVertex3f( 1.0f,-1.0f, 1.0f); // Top Right Of The Quad (Bottom)
glVertex3f(-1.0f,-1.0f, 1.0f); // Top Left Of The Quad (Bottom)
glVertex3f(-1.0f,-1.0f,-1.0f); // Bottom Left Of The Quad (Bottom)
glVertex3f( 1.0f,-1.0f,-1.0f); // Bottom Right Of The Quad (Bottom)
glColor3f(1.0f,0.0f,0.0f); // Color Red
glVertex3f( 1.0f, 1.0f, 1.0f); // Top Right Of The Quad (Front)
glVertex3f(-1.0f, 1.0f, 1.0f); // Top Left Of The Quad (Front)
glVertex3f(-1.0f,-1.0f, 1.0f); // Bottom Left Of The Quad (Front)
glVertex3f( 1.0f,-1.0f, 1.0f); // Bottom Right Of The Quad (Front)
glColor3f(1.0f,1.0f,0.0f); // Color Yellow
glVertex3f( 1.0f,-1.0f,-1.0f); // Top Right Of The Quad (Back)
glVertex3f(-1.0f,-1.0f,-1.0f); // Top Left Of The Quad (Back)
glVertex3f(-1.0f, 1.0f,-1.0f); // Bottom Left Of The Quad (Back)
glVertex3f( 1.0f, 1.0f,-1.0f); // Bottom Right Of The Quad (Back)
glColor3f(0.0f,0.0f,1.0f); // Color Blue
glVertex3f(-1.0f, 1.0f, 1.0f); // Top Right Of The Quad (Left)
glVertex3f(-1.0f, 1.0f,-1.0f); // Top Left Of The Quad (Left)
glVertex3f(-1.0f,-1.0f,-1.0f); // Bottom Left Of The Quad (Left)
glVertex3f(-1.0f,-1.0f, 1.0f); // Bottom Right Of The Quad (Left)
glColor3f(1.0f,0.0f,1.0f); // Color Violet
glVertex3f( 1.0f, 1.0f,-1.0f); // Top Right Of The Quad (Right)
glVertex3f( 1.0f, 1.0f, 1.0f); // Top Left Of The Quad (Right)
glVertex3f( 1.0f,-1.0f, 1.0f); // Bottom Left Of The Quad (Right)
glVertex3f( 1.0f,-1.0f,-1.0f); // Bottom Right Of The Quad (Right)
glEnd(); // End Drawing The Cube
glPopMatrix();
vector<particulas*> mundo;
void Muevelos()
//Dibujo las lineas del inicio
glBegin(GL_LINES);
glVertex3f(-RAD, -RAD, 0.0f);
glVertex3f(RAD, -RAD, 0.0f);
glVertex3f(RAD, -RAD, 0.0f);
glVertex3f(RAD, RAD, 0.0f);
glVertex3f(RAD, RAD, 0.0f);
glVertex3f(-RAD, RAD, 0.0f);
glVertex3f(-RAD, RAD, 0.0f);
glVertex3f(-RAD, -RAD, 0.0f);
glEnd();
for(int i=0;i<mundo.size();i++)
mundo[i]->Drawparticulas();
// Not using this yet
void animation(void)
for(int i=1;i<mundo.size();i++)
float xd = mundo[0]->x-mundo[i]->x;
float yd = mundo[0]->y-mundo[i]->y;
float zd = mundo[0]->x-mundo[i]->x;
float Distance = sqrt(xd*xd + yd*yd + zd*zd);
// Ill apply the newtons law.
//(mi*m2/D)g
float F=(mundo[0]->factor*mundo[0]->factor/Distance)*GE;
//Normalized Vector
float nx,ny,nz;
nx=mundo[i]->x/Distance;
ny=mundo[i]->y/Distance;
nz=mundo[i]->z/Distance;
mundo[i]->x+=F*nx;
mundo[i]->y+=F*ny;
mundo[i]->z+=F*nz;
void reshape(int x, int y)
if (y == 0 || x == 0) return; //Nothing is visible then, so return
//Set a new projection matrix
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
//Angle of view:40 degrees
//Near clipping plane distance: 0.5
//Far clipping plane distance: 20.0
gluPerspective(100.0,(GLdouble)x/(GLdouble)y,0,1000);
glMatrixMode(GL_MODELVIEW);
gluLookAt(-600,-600 , -600,
0, 0, 0,
0, 1, 0
);
glViewport(0,0,x,y); //Use the whole window for rendering
int main(int argc, char** argv)
mundo.resize(20);
mundo[0]=new particulas(0,0,0,2); // centro
for(int i=1;i<mundo.size();i++)
float x=-RAD/2.0 + rand()%RAD;
float y=-RAD/2.0 + rand()%RAD;
float z=-RAD/2.0 + rand()%RAD;
float r= 1+rand()%3;
// printf("%lf %lf %lf %lf\n",x,y,z,r);
mundo[i]=new particulas(x,y,z,r);
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_DEPTH | GLUT_DOUBLE | GLUT_RGBA);
glutInitWindowPosition(1920/2-WIDTH/2,1080/2-HEIGHT/2);
glutInitWindowSize(WIDTH,HEIGHT);
glutCreateWindow("Giu");
// glutInitWindowPosition(100, 100);
glEnable(GL_DEPTH_TEST);
//init();
gluLookAt(-600,-600 , -600,
0, 0, 0,
0, 1, 0
);
glutDisplayFunc(Muevelos);
glutReshapeFunc(reshape);
//Set the function for the animation.
//glutIdleFunc(animation);
glutMainLoop();
return 0;
【问题讨论】：
尝试渲染一个简单的几何图形并将其可视化。使代码更简单并重现问题。您正在使用什么 GPU/驱动程序？gluLookAt(-600,-600 , -600, 0, 0, 0, 0, 1, 0 ); 你的相机似乎在寻找别的地方！！
【参考方案1】：
gluPerspective() 的zNear 参数必须大于零。
您需要在gluLookAt() 之后添加一个glLoadIdentity()，否则您的模型视图矩阵将在第二次调整窗口大小后变成乱码。
您需要在显示回调结束时使用glutSwapBuffers()，以便您的后台缓冲区有朝一日可以真正进入前台缓冲区。
您的对象/视图缩放比例（可能）有问题。
一个工作示例：
#include <GL/glut.h>
#include <vector>
using namespace std;
#include <glm/glm.hpp>
#include <glm/gtx/norm.hpp>
using namespace glm;
struct Particle
dvec3 pos;
dvec3 vel;
double mass;
dvec3 force;
void Integrate( double dt )
const dvec3 accel = force / mass;
// semi-implicit euler
vel = vel + accel * dt;
pos = pos + vel * dt;
;
void Integrate( vector< Particle >& particles, double dt )
// zero out force vectors for this tick
for( size_t i = 0; i < particles.size(); ++i )
particles[i].force = dvec3( 0 );
// accumulate force vectors for each particle
for( size_t i = 0; i < particles.size(); ++i )
for( size_t j = i+1; j < particles.size(); ++j )
Particle& p1 = particles[i];
Particle& p2 = particles[j];
// http://en.wikipedia.org/wiki/Newton%27s_law_of_universal_gravitation#Vector_form
const double BigGee = 1.0;
const dvec3 diff = ( p2.pos - p1.pos );
const dvec3 rHat = glm::normalize( diff );
const double r2 = glm::length2( diff );
const dvec3 force = BigGee * ( ( p1.mass * p2.mass ) / r2 ) * rHat;
p1.force += force;
p2.force -= force;
// update positions/velocities
for( size_t i = 0; i < particles.size(); ++i )
particles[i].Integrate( dt );
vector< Particle > particles;
void display()
// use last frame time to calculate delta-t
static int last = glutGet( GLUT_ELAPSED_TIME );
int cur = glutGet( GLUT_ELAPSED_TIME );
double dt = ( cur - last ) / 1000.0;
last = cur;
Integrate( particles, dt );
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glMatrixMode( GL_PROJECTION );
glLoadIdentity();
double w = glutGet( GLUT_WINDOW_WIDTH );
double h = glutGet( GLUT_WINDOW_HEIGHT );
double ar = w / h;
glOrtho( -100 * ar, 100 * ar, -100, 100, -1, 1 );
glMatrixMode( GL_MODELVIEW );
glLoadIdentity();
// draw particles
glPointSize( 5 );
glEnableClientState( GL_VERTEX_ARRAY );
glVertexPointer( 3, GL_DOUBLE, sizeof( Particle ), &particles[0].pos[0] );
glDrawArrays( GL_POINTS, 0, particles.size() );
glDisableClientState( GL_VERTEX_ARRAY );
glutSwapBuffers();
void timer( int value )
glutPostRedisplay();
glutTimerFunc( 16, timer, 0 );
int main(int argc, char **argv)
particles.resize( 2 );
// "sun"
particles[0].pos = dvec3( 0, 0, 0 );
particles[0].vel = dvec3( 0, 0, 0 );
particles[0].mass = 100000;
// "planet"
particles[1].pos = dvec3( 50, 0, 0 );
particles[1].vel = dvec3( 0, -20, 0 );
particles[1].mass = 1;
glutInit( &argc, argv );
glutInitDisplayMode( GLUT_RGBA | GLUT_DEPTH | GLUT_DOUBLE );
glutInitWindowSize( 600, 600 );
glutCreateWindow( "GLUT" );
glutDisplayFunc( display );
glutTimerFunc( 0, timer, 0 );
glutMainLoop();
return 0;
【讨论】：
非常感谢这个准确的例子！我去看看。以上是关于OpenGL/Glut 无法在其上绘制 [的主要内容，如果未能解决你的问题，请参考以下文章