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I want to implement my own cursor in an OpenGL / GLUT window. The usual way to do this is to freeze the cursor (so it can't hit the edges of the screen) and keep track of its position yourself. I can make the onscreen cursor invisible using glutSetCursor(GLUT_CURSOR_NONE); and then inside of my glutPassiveMotionFunc callback move the pointer to the middle of the window using int centerX = (float)kWindowWidth / 2.0; int centerY = (float)kWindowHeight / 2.0; int deltaX = (x - centerX); int deltaY = (y - centerY); mouseX += deltaX / (float)kWindowWidth; mouseY -= deltaY / (float)kWindowHeight; glutWarpPointer( centerX, centerY ); This works in that it keeps the pointer stuck to the middle of the window. The problem is that when I am drawing the 'OpenGL' mouse (inside of the glutDisplayFunc() callback) it is extremely jerky. I have looked online and found that there can be an issue where glutWarpPointer() causes the glutPassiveMotionFunc callback to be called again, resulting in a loop, but this doesn't seem to happen here. I'm on Mac OS X and I found a post saying that CGDisplayMoveCursorToPoint was a better fit for this. Calling CGDisplayMoveCursorToPoint works but the movement is still very jerky (and I seem to get a lot of events where x and y are both 0). In any case, I'd like this to work on Linux as well so a Mac only solution is not ideal (but I'm okay having to do different things on the different systems). I've reduced this to a testcase. #include <stdio.h> #include <OpenGL/OpenGL.h> #include <GLUT/GLUT.h> int curX = 0; int curY = 0; void display() { glClearColor( 0.0, 0.0, 0.0, 1.0 ); glClear( GL_COLOR_BUFFER_BIT ); float vx = (float)curX / 300.0 + 0.5; float vy = (float)curY / 300.0 + 0.5; glColor3f( 1.0, 0.0, 0.0 ); glBegin( GL_POINTS ); glVertex3f( vx, vy, 0.0 ); glEnd(); glutSwapB

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