Bug 1206 - Security: Clear exposed framebuffer after creation and before visibility

Experimenting w/ no GLEventListener attached to an GLAutoDrawable,
e.g. GLWindow (onscreen), GLJPanel (fbo offscreen),
indeed on some GL implementations the default framebuffer is uninitialized
and hence shows garbage.

GLDrawableHelper.setViewportAndClear(..)
 - Clear framebuffer after setting viewport
 - Called from:
   - public final void init(..)
   - public final void reshape(..)

 - Method is used independent of GLEventListener,
   hence this simplifies implementation: removes 'setViewport' criteria
   for init, display, reshape: it is always performed!

Note: We only attempt to help against leaking un-initialized framebuffer content
not against user-app faults, we do not clear a 2nd-buffer (double-buffering).

Note: We may still be late at resize, i.e. small noisy flickering might be visible.
This might be due to lack of proper vsync.

0 files changed, 0 insertions, 0 deletions