- use GL to copy to display buffers, to work on any platform - wait for vsync is optional - refactor all buffer functionality into wnull_buffer.[ch] - don't get confused if the current context is destroyed - intercept glBindFramebuffer(GL_FRAMEBUFFER,0) - intercept other erroneous framebuffer function calls - a bunch of changes suggested by reviewer Emil Velikov Signed-off-by: Frank Henigman <fjhenigman@google.com>