ganzsz

I have set up a development environment in IDEA using http://www.minecraftforge.net/forum/index.php/topic,21354.0.html. Minecraft client runs normally, but when I go to a world it renders fine for a moment, and then every block turns either completely black or invisible (collision boundary still showing on mouseover.) I've set up a new environment with 1.7.10, The same problem occurs, it renders fine, untill I look down, then everything turns black