cube will not rotate, have no idea why?

saisoft · 2003-02-09T16:53:57

I''m sorta of new, its been a while, why isn''t this cube rotating on the screen, here is the code #include <windows.h> #include <gl/glut.h> void display(void); void ChangeSize(GLsizei w, GLsizei h); double rot = 45.0f; int main(int argc, char** argv) { glutInit (&argc, argv) ; glutInitDisplayMode (GLUT_DOUBLE | GLUT_RGB) ; glutInitWindowSize (800, 600) ; glutInitWindowPosition (100, 100) ; glutCreateWindow ("First Chapter - Opening an OpenGL Window") ; glClearColor(0.0f,0.0f,0.0f,1.0f); glutDisplayFunc(display); glutReshapeFunc(ChangeSize); glutMainLoop(); return 0 ; } void display() { glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); // Clear Screen And Depth Buffer glLoadIdentity(); // Done Drawing The Quad glTranslatef(500.0f,300.0f,0.0f); glRotatef(rot,0.0,1.0,0.0); glBegin(GL_QUADS); //top glColor3f(1.0f,0.0f,0.0f); glVertex3f(0.0f,0.0f,0.0f); glVertex3f(0.0f,0.0f,-100.0f); glVertex3f(100.0f,0.0f,-100.0f); glVertex3f(100.0f,0.0f,0.0f); //bottom glColor3f(0.0f,1.0f,0.0f); glVertex3f(0.0f,-100.0f,0.0f); glVertex3f(0.0f,-100.0f,-100.0f); glVertex3f(100.0f,-100.0f,-100.0f); glVertex3f(100.0f,-100.0f,0.0f); //front glColor3f(0.0f,0.0f,1.0f); glVertex3f(0.0f,0.0f,0.0f); glVertex3f(100.0f,0.0f,0.0f); glVertex3f(100.0f,-100.0f,0.0f); glVertex3f(0.0f,-100.0f,0.0f); //back glColor3f(1.0f,1.0f,0.0f); glVertex3f(0.0f,0.0f,-100.0f); glVertex3f(100.0f,0.0f,-100.0f); glVertex3f(100.0f,-100.0f,-100.0f); glVertex3f(0.0f,-100.0f,-100.0f); //left glColor3f(1.0f,0.0f,1.0f); glVertex3f(0.0f,0.0f,0.0f); glVertex3f(0.0f,0.0f,-100.0f); glVertex3f(0.0f,-100.0f,-100.0f); glVertex3f(0.0f,-100.0f,0.0f); //right glColor3f(0.0f,1.0f,1.0f); glVertex3f(100.0f,0.0f,0.0f); glVertex3f(100.0f,0.0f,-100.0f); glVertex3f(100.0f,-100.0f,-100.0f); glVertex3f(100.0f,-100.0f,0.0f); glEnd(); rot+=2.0f; glutSwapBuffers(); } void ChangeSize(GLsizei w, GLsizei h) { if(h == 0) h = 1; glViewport(0,0,w,h); glMatrixMode(GL_PROJECTION); glLoadIdentity(); if(w<=h) glOrtho(0,800,0,600*h/w,1.0f,-1.0f); else glOrtho(0,800*w/h,0,600,1.0f,-1.0f); glMatrixMode(GL_MODELVIEW); glLoadIdentity(); }

Graphics and GPU Programming Programming

Started by saisoft February 08, 2003 02:13 PM

13 comments, last by saisoft 21 years, 2 months ago

Californium

100

February 08, 2003 06:26 PM

Remember that if it''s a wire frame cube, there are two ways of looking at it. The wrong way makes it look distorted and warping when it''s rotating. I didn''t read your code, sorry.

This post will self-destruct in 5 seconds...Actually, it's just Benjamin Bunny doing his thing.

Thorin_nz

122

February 09, 2003 03:15 AM

Its because it was being displayed 2d due to the projection matrix used, When a proper 3d projection matrix is used its fine

saisoft

122

Author

February 09, 2003 02:20 PM

ok i changed it to perspective view, but now I don''t see the cube, I used the code posted above

/source void ChangeSize(GLsizei w, GLsizei h)
{
if (h==0) // Prevent A Divide By Zero By
{
h=1; // Making Height Equal One
}

glViewport(0, 0, w, h); // Reset The Current Viewport

glMatrixMode(GL_PROJECTION); // Select The Projection Matrix
glLoadIdentity(); // Reset The Projection Matrix

// Calculate The Aspect Ratio Of The Window
// (Field of view, aspect ratio, near, far)
gluPerspective(45.0f,(GLfloat)w/(GLfloat)h,0.1f,100.0f);

glMatrixMode(GL_MODELVIEW); // Select The Modelview Matrix
glLoadIdentity(); // Reset The Modelview Matrix
} /source