Well that format can certainly handle 8-bits of alpha, so it must be something else.<br><br>Lomax,<br><br>If you render your 3D image on a solid black background and then enable anti-aliasing, what you'll end up with is an image that has been pre-multiplied by the alpha component. You can create an alpha mask by re-rendering after cranking the ambient lighting up to solid white, then make the color of your polys white, and leave anti-alias enabled. Depending on how your engine performs alpha blending, you might want to invert the resulting alpha mask.<br><br>From the canonical equation for alpha blending:<br><br>dC = (sC * A) + dC * (1 - A)<br><br>Since we have pre-multiplied the alpha by the source color (sC), and we're storing the inverse alpha in the mask, the equation above becomes:<br><br>dC = sC + dC * A<br><br>I think I went over all of this in some previous posts about how to implement alpha blending efficiently, but I never thought about it from an artist's perspective on how to create those alpha masks and pre-multiplied source images. Turns out it's easier than I thought. One of these days I should write the code to do this and see if it actually works.<br><br>Here's some test images I created quickly with Rhino3D (don't laugh, I'm a programmer, not an artist)<br><br>
<br>Source image (sprite)<br><br>
<br>Alpha mask<br><br>
<br>Inverse alpha mask<br><br>Grab the images and then zoom-in to view the anti-aliased edges.<br><br><br><br>