title: glStencilOp -- GL_INCR_WRAP GL_DECR_WRAP. stencil mask behaviour
body: <p>OpenGL documentation for glStencilOp isn't clear on what happens for increment and decrement operations in the presence of stencil masks.  It seems to imply that the mask will be ignored for increment and decrement operation.</p>
  
  <p>Can anyone confirm/refute that?</p>
  
  <p>Thanks</p>