Hi, I am very new to OpenGl. But I have to learn it. So I have a question: Why does the following Code show nothing? #include <stdlib.h> #include <GL/glut.h> #include <cmath> using namespace std; #define KOORDINATENACHSE 1 void init(); void renderScene(); void reshapeWindow(int,int); int main(int argc, char **argv) { glutInit(&argc, argv); glutInitDisplayMode(GLUT_DEPTH | GLUT_SINGLE| GLUT_RGBA); glutInitWindowPosition(100,100); glutInitWindowSize(800,600); glutCreateWindow("OpenGL"); init(); glutDisplayFunc(renderScene); glutReshapeFunc(reshapeWindow); glutMainLoop(); return 0; } void init() { glClearColor(1.0F,1.0F,1.0F,1.0F); glEnable(GL_DEPTH_TEST); glShadeModel(GL_FLAT); glMatrixMode(GL_PROJECTION); glLoadIdentity(); gluPerspective(80,1.0,0.1,100); glMatrixMode(GL_MODELVIEW); glLoadIdentity(); } void renderScene() { glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); glMatrixMode(GL_MODELVIEW); glLoadIdentity(); gluLookAt(3,2,5,0,0,0,0,0,1); glNewList(KOORDINATENACHSE,GL_COMPILE_AND_EXECUTE); glBegin(GL_LINES); //X-Achse: rot glColor3f(1.0,0.0,0.0); glVertex3d(0.0,0.0,0.0); glVertex3d(10.0,0.0,0.0); //Y-Achsr: gruen glColor3f(0.0,1.0,0.0); glVertex3d(0.0,0.0,0.0); glVertex3d(0.0,10.0,0.0); //Z-Achse: blau glColor3f(0.0,0.0,1.0); glVertex3d(0.0,0.0,0.0); glVertex3d(0.0,0.0,10.0); glEnd(); glEndList(); glBegin(GL_QUADS); glColor3f(0.5,0.3,0.9); glVertex3d(-100,-100,0); glVertex3d(100,-100,0); glVertex3d(100,100,0); glVertex3d(-100,100,0); glEnd(); glFlush(); } void reshapeWindow(int w,int h) { if(h == 0) h = 1; float ratio = 1.0* w / h; // Reset the coordinate system before modifying glMatrixMode(GL_PROJECTION); glLoadIdentity(); // Set the viewport to be the entire window glViewport(0, 0, w, h); cout<<"reshape"<<endl; }

try putting some sort of loop around the glutdisplayfunc().

because currently all your program is doing is running through everything once.

aside from that it looks like it may work. if not well go from there :).

edit: another note, you may be more likely to get a reply with a better title ;)

Thanks. The problem was solved. I played a little bit with the camera and uses now Double Buffering. But since Qt works fine on my computer, I won't use Glut anymore (perhaps :))

bye

Quote: Original post by escudo825
try putting some sort of loop around the glutdisplayfunc().

because currently all your program is doing is running through everything once.

aside from that it looks like it may work. if not well go from there :).

edit: another note, you may be more likely to get a reply with a better title ;)

glutMainLoop() will repeatedly call his drawing function.

Quote: Original post by Ezbez

Quote: Original post by escudo825
try putting some sort of loop around the glutdisplayfunc().

because currently all your program is doing is running through everything once.

aside from that it looks like it may work. if not well go from there :).

edit: another note, you may be more likely to get a reply with a better title ;)

glutMainLoop() will repeatedly call his drawing function.

Only if there is a reason to do so. If the window doesn't need a redraw, the mainloop won't call the display function. Only things like a window reshape/reposition, revealing previously hidden parts of the window, and so will trigger a redraw. If you need repeated callbacks, you need to so by calling glutPostRedisplay, preferably in the idle callback.