glutPostRedisplay

glutPostRedisplay marks the normal plane of current window as needing to be redisplayed. glutPostWindowRedisplay works the specified window as needing to be redisplayed. After either call, the next iteration through glutMainLoop , the window's display callback will be called to redisplay the window's normal plane. Multiple calls to glutPostRedisplay before the next display callback opportunity generates only a single redisplay callback. glutPostRedisplay may be called within a window's display or overlay display callback to re-mark that window for redisplay.

Logically, normal plane damage notification for a window is treated as a glutPostRedisplay on the damaged window. Unlike damage reported by the window system, glutPostRedisplay will not set to true the normal plane's damaged status (returned by glutLayerGet(GLUT_NORMAL_DAMAGED) .

If the window you want to post a redisplay on is not already current (and you do not require it to be immediately made current), using glutPostWindowRedisplay is more efficient that calling glutSetWindow to the desired window and then calling glutPostRedisplay .