Basic GLUT library

• Here is a complete online manual.

Window initialization

• glutInit(int *argc, char **argv)
  • initializes GLUT library
• glutInitWindowSize(int width, int height)
• glutInitWindowPosition(int x, int y)
  • specifies size, position of window to be created by next glutCreateWindow
• glutInitDisplayMode(OR'd bit string args)
  • specify display mode: some include...
    • GLUT_RGBA, GLUT_INDEX: rgb, color map modes
    • GLUT_SINGLE, GLUT_DOUBLE: single, double buffering
    • GLUT_DEPTH: depth buffer
• int glutCreateWindow(char *name)
  • create window specified by the above
  • integer ID for window returned
• glutSetWindow(int), glutGetWindow(int)
  • set or get the specified window (via ID number)

Callback registration

• glutDisplayFunc(void (*func)(void))
  • assigns function to call when current window must be redisplayed
• glutReshapeFunc(void (*func) (int width, int height))
  • function to call when current window is reshaped; the parameters are the new size of reshaped window
• glutIdleFunc(void (*func)(void))
  • function to call when no activity occurring (eg. for animation)
• glutKeyboardFunc(void (*func)(unsigned char key, int x, int y))
  • sets key processing routine
  • x and y are mouse coordinates when the key 'key' was pressed
  • see glutGetModifiers for state of modifier keys (eg. ctrl,...)
• glutMouseFunc(void (*func)(int button, int state, int x, int y))
  • mouse function callback
  • button: GLUT_LEFT_BUTTON, GLUT_MIDDLE_BUTTON, GLUT_RIGHT_BUTTON
  • state: GLUT_UP, GLUT_DOWN
  • x, y: mouse coordinates
• glutMotionFunc (void (*func)(int x, int y))
  • function to call when mouse is moving in window, when a button is pressed
• glutPassiveMotionFunc(void (*func)(int x, int y))
  • function to call when mouse is moving in window, when no buttons are pressed
• glutMainLoop(void)
  • starts GLUT processing; should be called only once in program

Colour Map Management

• glutSetColor(int index, GLfloat red, GLfloat green, GLfloat blue)
  • set index to specified colour
• GLfloat glutGetColor(int index, int component)
  • gets colour in index, specified by component GLUT_RED, GLUT_GREEN, GLUT_BLUE

Misc

glutGet(GLenum state)

• gets a particular GLUT state value
• eg. GLUT_WINDOW_WIDTH, GLUT_WINDOW_BUFFER_SIZE, etc

glutPostRedisplay(void)

• marks current window as needing redisplay by glutDisplayFunc

glutSwapBuffers(void)

• Swaps buffers when doing double buffering during animation

Examples

Look here for basic examples.

Look here for advanced examples (local access only).

COSC 3P98 Computer Graphics
Brock University
Dept of Computer Science

Copyright © 2000 Brian J. Ross
http://www.cosc.brocku.ca/Offerings/3P98/course/lectures/OpenGL/glut_ref.html
Last updated: September 18, 2006