The GPU ignores that register when clearing, but OpenGL obeys the glDepthMask parameter, so we set the depth mask to GL_TRUE when clearing the depth buffer. It will be restored to the correct value automatically on the next draw call.
The GPU ignores that register when clearing, but OpenGL obeys the glDepthMask parameter, so we set the depth mask to GL_TRUE when clearing the depth buffer. It will be restored to the correct value automatically on the next draw call.