Programming and Graphics

280 Introduction to C++ Programming and Graphics

//--- main:

int main(int argc, char **argv)

{

glutInit(&argc, argv);

glutInitDisplayMode(GLUTDEPTH | GLUTSINGLE | GLUTRGBA);

glutInitWindowPosition(100,100);

glutInitWindowSize(320,320);

win=glutCreateWindow("Goulis");

glClearColor(0.2,0.5,0.2,0.2);

glutDisplayFunc(showme); // initial display

showmenu();

glutDisplayFunc(showme);

glutMainLoop();

return 0;

}

//--- showme:

void showme(void)

{

glClear(GLCOLORBUFFERBIT);

if(drawflag==1){

glutPostRedisplay();}

else if(drawflag==2){

glutWireTeapot(0.5);}

else if(drawflag==3){

glBegin(GLTRIANGLES);

glVertex3f(-0.9,-0.5,0.0);

glVertex3f( 0.3,-1.0,0.0);

glVertex3f( 0.0, 1.0,0.0);

glEnd();}

glFlush();

}

//--- showmenu:

void showmenu(void)

{

submenuid=glutCreateMenu(menu); // Create a sub-menu

glutAddMenuEntry("teapot", 2); // Add sub menu entries

glutAddMenuEntry("triangle", 3); // Create an entry

menuid=glutCreateMenu(menu); // Create the menu

glutAddMenuEntry("Clear", 1); // Create an entry

glutAddSubMenu("Draw", submenuid); // Create an entry