[Edit] ah ok they clarify later as a performance enhancement. I think it was pretty integral to the algorithm, but ok.
Wait why do they say painter's algorithm. Comanche and other such voxel terrain engines went front to back and never had overdraw.
Wait why do they say painter's algorithm. Comanche and other such voxel terrain engines went front to back and never had overdraw.
Great for a helicopter game, Less so for general flight sim.
That was a large part of how games were designed back in the day. Start with what you have the ability to do, find the game that matches what you can do.
Edit: To support roll, the renderer essentially rendered the voxel terrain into a frame buffer and then applied camera transformations that gave the appearance of a fully rotating viewpoint. The terrain itself was not being raycast through a true 3D voxel volume.
it tracks how tall each columns write is so you can use it to only write the diff between it and the voxel behind it, skipping writing anything at all if the voxel behind is shorter than the current height.
So once you're done rendering front-to-back, you've got a y-buffer of highest-writes you can slap your blue sky across from highest-to-screentop on each line, avoiding the need to clear by write the sky to the full screen before starting the render.