Even the code is all right(coz I run the example onesfor test)
and all the libraries are imported
Things do not show up but only just grey screen
and there are red sentences below like:
when I copy and paste,it shows like this:
Framebuffer error (unknown error), rendering will probably not work as expected OpenGL error 1286 at bot beginDraw(): invalid framebuffer operation OpenGL error 1286 at top endDraw(): invalid framebuffer operation OpenGL error 1286 at bot endDraw(): invalid framebuffer operation
