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0 pointsShabaz14y ago0 comments

Someone correct me if I'm wrong, but I'm not sure that either Voxatron or 3D Dot Game Heroes actually use voxel based rendering. They may or may not store their models as voxels but I'm pretty sure that at some point it's converted into a polygonal model and shoved into a traditional polygon based rasterizing pipeline. As opposed to doing some raycasting into a datastructure containing voxels (e.g. an octree), which from my very limited understanding is roughly what a voxel based rendering pipeline looks like.

Doesn't take away the fact that both games look pretty damn nifty though.

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3 comments · 1 top-level

skymt14y ago· 2 in thread

Voxatron absolutely uses "true" voxel rendering.

> Voxatron is based on a virtual 128x128x64 display. It's a buffer of 3d video memory that is rendered out to the screen at the end of each frame, much as an old-school 2d display is. You can POKE bytes into the virtual memory, and they come out as voxels. I don't compromise on this -- even the menus are drawn into the voxel display. Hopefully one day I can get hold of a real physical 128x128x64 display and play Voxatron on it with almost no modification.

> The renderer is written in software (C + SDL). Each frame, scan through the virtual video memory back to front and look for voxels that have empty neighbours. If they are exposed, I transform the corners of a cube intro screen space and scan-render the polygon. Shadows are done with a traditional shadow-map but sampled with a filter to get the soft shadows.

http://www.lexaloffle.com/bbs/?tid=260

ShabazOP14y ago

I didn't realize they use their own renderer. Pretty neat.

I guess I was thinking that the raycasting approach I've seen used in some of the sparse voxel octree stuff I read wouldn't make sense when you want the blockiness of voxels to actually show up very clearly, plus that it looked like you could achieve the same look using polygon based cubes. Guess I should've done a bit more research.

extension14y ago

You can do something like Voxatron with raycasting and it will look the same. It would just be inefficient with such big voxels. It becomes efficient when the voxels approach the size of 2D screen pixels.

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