Accum Buffer + Anti-Aliasing Weirdness

[Gaara]

Hey all.  I was trying out some things with the accumulation buffer to have some cool fullscreen motion blur effects and I wanted to have some anti-aliasing to smooth out the edges of the models.  Well, heres what I got when I did the accum buffer with 6x anti-aliasing...



It still runs, but looking like that.  I'm not sure if its LWJGL, OpenGL or my ATI card (9800pro).  It does work, however, with 4x and below anti-aliasing.

Code for accum buffer to do motion blur:

GL11.glAccum( GL11.GL_MULT, .90f );
GL11.glAccum( GL11.GL_ACCUM, .10f );
GL11.glAccum( GL11.GL_RETURN, 1f );

Code for the PixelFormat of the Display with 6x anti-aliasing:

Display.create( new PixelFormat( 0, 4, 1, 1, 6, 0, 1, 1, false ) );

Any thoughts?

[Matzon]

ati doesn't do more than 4x AA ?

[Gaara]

Ahh, that would explain it.  Thanks.

[darkprophet]

I wouldn't use the accumulation buffer if I was you. Alot of hardware "supports" it, but via software mode.

Much safer to render to texture either using EXT_fbo, pbuffer or just a straight out copy from frame buffer, then make a few fullscreen quads with varying alpha colours and blit the textures onto those textures...

DP

[Gaara]

Cool, thanks for the advice.  I'll have to give that a try.