>
> ...for those whose only option is an Intel graphics chip, the following might be useful:
> After having this exact problem on my rather old laptop, it turned out that the GLCapabilities object I was using to create my GLCanvas was asking for a 24-bit depth buffer:
>
> GLProfile profile = GLProfile.get(GLProfile.GL2);
> GLCapabilities capabilities = new GLCapabilities(profile);
> System.out.println("caps: " + capabilities.getDepthBits());  // Returns 24
>
> Now I'm assuming that my graphics chip can't fulfil this request, because later when I come to query the actual depth buffer size, it's zero...
>
> public void init(GLAutoDrawable drawable) {
>   ...
>   GL2 gl2 = drawable.getGL().getGL2();
>   IntBuffer buff = IntBuffer.allocate(1);
>   gl2.glGetIntegerv(GL2.GL_DEPTH_BITS,buff);
>   System.out.println("Depth buffer: " + buff.get(0));  // Prints 0; oops, our depth buffer looks a little shallow...
>   ...
> }
>
> I was able to work around this on my system by changing the depth requested by the GLCapabilities:
>
> capabilities.setDepthBits(16);  // Gears now render correctly!
>
> I'm not yet sure as to the ideal way to incorporate this workaround in my code; it'd be nice if I could find out in advance the best non-zero depth buffer value to ask for. But for the moment this seems to work. Hope it's useful to someone.