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0 pointstimknauf14y ago0 comments

I can see how animations might be difficult, depending on what sort of data structure one uses to store the voxel data. But why would you not be able to see the same object from different angles?

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wladimir14y ago· 3 in thread

I think he means that you cannot rotate an object and keep it aligned to the voxel grid at the same time. It would be a lossy operation, and require interpolation, just like rotating an image on a 2D grid.

roel_v14y ago

But if the resolution of your grid is smaller than the size of the voxel, that wouldn't matter much - and you could keep rounding errors in check by anchoring larger units of voxels at a certain location in space. I can see the drawbacks of the voxel cloud approach (requires much memory, what algorithm is fast enough to do voxel culling on such a massive amount of data, what about animation) but the 'can't do rotation' doesn't seem like a particularly strong argument (unless I'm misunderstanding the actual argument, which is very well possible...)

wladimir14y ago

I'm not saying it is entirely impossible. However, rotating volume data (which voxels are) is computationally a lot more intensive. With polygonal objects you can just change the transformation matrix and re-render the screen and you're done. At most, you have to deform the vertices that make up the outer shell of the object to do things like make a person walk.

With voxels, you'd have to recompute all the voxels of the object on a 3d grid. Also there are issues with ragged boundaries, which can be prevented by using antialiasing, but which is probably trickier (=more computationally intensive) than in 2D...

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ajuc14y ago

Rotatin (in general - transforming) voxels in real time is difficult compared to polygons, because with polygons you only transform vertices, and in voxels you have to transform every voxel.

EDIT: If you are spekaing about preprocessing data - yes - you can rotate as much as you want, the only problem will be that object instanced 1000 times with different orientation/scale will take 1000 times more memory than object instanced 1000 times with the same orientation/scale. With polygons there is no difference.

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4 comments · 1 top-level

wladimir14y ago· 3 in thread

roel_v14y ago

wladimir14y ago

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ajuc14y ago

Rotatin (in general - transforming) voxels in real time is difficult compared to polygons, because with polygons you only transform vertices, and in voxels you have to transform every voxel.

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