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300 points LaserDiscMan | 1 comments | | HN request time: 0s | source
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amlib ◴[] No.46222841[source]
> Tessellation (up to 2x) to reduce issues with large polygons

From the videos I've watched there is still insane amounts of affine transformation texture warping, is that because it's not enable or because 2x is not enough?

I guess they will need to also redo all level geometry to be more amenable to tesselation... I guess that's why many ps1 games had blocky looking levels.

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mewse-hn ◴[] No.46223821[source]
I see a lot of texture warp like you mentioned but I'm not seeing the geometry popping (wobble?) that was a hallmark of ps1 games, I'm guessing they're using soft floating point for the geometry and doing perspective-correct texture mapping would just be too expensive for decent frame rate
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malucart ◴[] No.46224242[source]
it's not possible to have either subpixel vertex precision or perspective correct mapping with the PS1 GPU, as it only takes 2D whole-pixel coordinates for triangle vertices. (contrary to popular belief, N64 also uses exclusively fixed point for graphics btw, it just has subpixel units.) better tessellation can mitigate the perspective issues by a lot, but the vertex snapping is unsolvable, and it is indeed present here. look closer and you might see it.
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1. eru ◴[] No.46228499[source]
Interesting!

I guess you could pretend to have sub-pixel precision on the PS1, if you did it manually? Eg change the colours around 'between pixels' or something like that?

But that would probably get very expensive very soon.