glut_menu.zip_glut menu_glutmenu

#include<GL/glut.h> #define RED 1 #define GREEN 2 #define BLUE 3 #define WHITE 4 float angle = 0.0; float red=1.0, blue=1.0, green=1.0; void changeSize(int w, int h) { // Prevent a divide by zero, when window is too short // (you cant make a window of zero width). 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); // Set the correct perspective. gluPerspective(45,ratio,1,1000); gluLookAt(0.0,0.0,5.0, 0.0,0.0,-1.0, 0.0f,1.0f,0.0f); glMatrixMode(GL_MODELVIEW); } void renderScene(void) { glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); glLoadIdentity(); glRotatef(angle,0.0,1.0,0.0); glColor3f(red,green,blue); glBegin(GL_TRIANGLES); glVertex3f(-0.5,-0.5,0.0); glVertex3f(0.5,0.0,0.0); glVertex3f(0.0,0.5,0.0); glEnd(); angle++; glutSwapBuffers(); } void processMenuEvents(int option) { switch (option) { case RED : red = 1.0; green = 0.0; blue = 0.0; break; case GREEN : red = 0.0; green = 1.0; blue = 0.0; break; case BLUE : red = 0.0; green = 0.0; blue = 1.0; break; case WHITE : red = 1.0; green = 1.0; blue = 1.0; break; } } void createGLUTMenus() { int submenu; submenu = glutCreateMenu(processMenuEvents); glutAddMenuEntry("Red",RED); glutAddMenuEntry("Blue",BLUE); glutAddMenuEntry("Green",GREEN); glutAddMenuEntry("White",WHITE); glutAttachMenu(GLUT_RIGHT_BUTTON); } void main(int argc, char **argv) { glutInit(&argc, argv); glutInitDisplayMode(GLUT_DEPTH | GLUT_DOUBLE | GLUT_RGBA); glutInitWindowPosition(100,100); glutInitWindowSize(320,320); glutCreateWindow("glut menu demo"); glutDisplayFunc(renderScene); glutIdleFunc(renderScene); glutReshapeFunc(changeSize); //call our function to create the menu createGLUTMenus(); glutMainLoop(); }