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gleps
01-13-2010, 06:44 PM
I am using glut.
when the program runs, and I drag the window to a new location, one of the objects moves position and also gets smaller. When I resize the window, it goes back to where it should be. Its not making sense to me.



#include <GLUT/glut.h>
#include <stdlib.h>

void init(void)
{
glClearColor (0.0, 0.0, 0.0, 0.0);
glShadeModel (GL_FLAT);
}

void display(void)
{
glClear(GL_COLOR_BUFFER_BIT);
glColor3f(1.0, 1.0, 1.0);


glTranslatef(0, -3.0, -10);
glutSolidSphere(1.0, 10, 8); /* mid sphere */ //this is the one that changes


glLoadIdentity();
glTranslatef(-3, -3.0, -10);
glutWireSphere(1.0, 10, 8); /* left sphere */

glLoadIdentity();
glTranslatef(3, -3.0, -10);
glutWireSphere(1.0, 10, 8); /* right sphere */

glutSwapBuffers();

}

void reshape(int w, int h)
{
glViewport (0, 0, (GLsizei) w, (GLsizei) h);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluPerspective(65.0, (GLfloat) w/(GLfloat) h, 1.0, 20.0);
glMatrixMode (GL_MODELVIEW);
glLoadIdentity();


}

int main(int argc, char** argv)
{
glutInit(&amp;argc, argv);

glutInitDisplayMode (GLUT_DOUBLE | GLUT_RGB);
glutInitWindowSize (1024, 768);
glutInitWindowPosition (100, 100);
glutCreateWindow (argv[0]);
init ();
glutDisplayFunc(display);
glutReshapeFunc(reshape);
// glutMouseFunc(mouse);
// glutKeyboardFunc(keyb);
glutMainLoop();
return 0;
}


anyone know why this is happening?

btw im using:
GLUT
mac os x 10.4 ppc
xcode

scratt
01-13-2010, 08:52 PM
Not quite sure about the resizing, but glut needs to be told to redraw stuff on certain actions, or at a designated refresh rate. It doesn't just keep drawing your view. So it is probably related to that.

When you resize the window reshape(..) is called and this will setup your matrices again and then display(..) will redraw your objects correctly.

Check this web page out : http://www.lighthouse3d.com/opengl/glut/index.php?gameglut