I'm attempting to anti alias by rendering to a larger texture then scaling down the texture. My code looks like this

glViewPort(0,0,GraphicsWidth()*2,GraphicsHeight()*2)

glFrustum(0,Graphicswidth()*2,0,GraphicsHeight()*2,1,1000)

glDrawElements()

glViewPort(0,0,GraphicsWidth(),GraphicsHeight())

glFrustum(0,GraphicsWidth(),0,GraphicsHeight(),1,1000)

For some reason it's only rendering the bottom left corner of the FBO.

http://www.opengl.org/sdk/docs/man2/xhtml/glFrustum.xml
glFrustum — multiply the current matrix by a perspective matrix

Before applying the frustum-matrix you have to reset the matrix first (glLoadIdentity), push and pop it (glPushMatrix, glPopMatrix) or use some other method (e.g. glLoadMatrix)

Edit: Or more likely you are using glFrustum wrong. The docs say void glFrustum(left, right, bottom, top, nearVal, farVal) - in your example code you are not in the center with your matrix.

- Martin