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Outcast, which uses a combined voxel-polygon 3D rendering engine, Appeal's Paradise , has an annoying aliasing problem when looking close to surfaces.
In trying to figure out why this happens (and not having any success with Outcast's developer, Appeal), I came across a paper about volume graphics (circa 1993--a tad old for the computing industry, eh?). Scroll down to "4. Disadvantages of Volume Graphics" (no direct link). The last sentence of the first paragraph and the second paragraph:
Since the continuous object is reconstructed by sampling the discrete data during rendering, a low resolution volume yields high aliasing artifacts (row 3 in Table 2). This becomes especially apparent when zooming in on the 3D raster. When naive rendering algorithms are used, the 3D discrete points may appear to be parted from each other, and may cause the appearance of holes. Nevertheless, this can be alleviated to some extent in ways similar to those adopted by 2D raster graphics, such as employing either reconstruction techniques (e.g. supersampling, filtering) or a high-resolution volume buffer."
I think that's why this "domino-stacking" effect happens when turning (also called rotation, part of transformation). Apparently, not enough "supersampling", "filtering" (bilinear texture filtering?), or "high-resolution volume buffers" aren't being used in Paradise.
I think voxels should only be used up to certain distances from the viewer, at which time polygons will replace voxels for more detailed, upclose objects like the ground (out to a certain distance to when voxels take over), stairs, etc--basically everything out to a certain distance, actually.
A lot of people are hyping about Outcast's graphics, despite its low resolutions (only up to 512x384 max) and severe aliasing. Now I'm not denying Outcast isn't impressive, but I still have problems with collision detection, character control, terrible dialog (obviously non-native English linguists wrote it), and slow dialog menu selection response times. See Outcast Central's forum (down) for some of my posts about these issues.
I feel polygons are better for closeup rendering than voxels. Voxels just look too alised in comparison. Voxels may be fine for medical scanners and scientific simulations, but they don't seem to work too well in games that simulate realistic environments up close like Outcast attempts to do.
Considering Appeal and Novalogic (Delta Force series) have announced dropping support for voxels in their upcoming sequels, I think it's safe to say voxels are dead (for now anyway) in the computer gaming industry. Perhaps if voxel accelerators become more practical and cheaper will voxels make a comeback but for now they just make games look like crap, in my opinion.
See how Outcast compares to other games in the 3D Game Comparison.
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