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Rasterizer: A GPU-accelerated 2D vector graphics engine in ~4k LOC

(github.com)
168 points mindbrix | 3 comments | 01 Sep 25 07:56 UTC | HN request time: 0s | source
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delhanty ◴[03 Sep 25 11:12 UTC] No.45114409[source]▶
Congratulations!

Can you say how the it's similar and how it's different to superficially similar sounding work?

(1) https://github.com/linebender/vello , dual Apache/MIT, by Raph Levien et al

(2) https://sluglibrary.com/ , proprietary, by Eric Lengyel (Terathon)

replies(1): >>45136148 #
mindbrix ◴[05 Sep 25 08:04 UTC] No.45136148[source]▶
Slug is primarily designed for text rendering.

Vello is general purpose, like Rasterizer, but is based on GPU compute. Rasterizer uses the 'traditional' GPU pipeline. Performance numbers for both look very competitive, although Vello seems to have issues with GPU lock up at certain zoom scales. Rasterizer has been heavily tested with huge scenes at any scale.

replies(2): >>45137261 #>>45137617 #
1. cubefox ◴[05 Sep 25 12:11 UTC] No.45137617[source]▶
Stupid question: Why not use the hardware (fixed function) rasterizer inside the GPU? I guess that one is only optimized for triangles.
replies(2): >>45137703 #>>45137965 #
2. mindbrix ◴[05 Sep 25 12:24 UTC] No.45137703[source]▶
Good question and answer ;-)
3. mindbrix ◴[05 Sep 25 12:54 UTC] No.45137965[source]▶
The longer answer is that using straight-edged geometry to represent curves is a resolution-dependent operation, e.g. a full screen circle may need to be flattened to an 80-sided polygon.

Rasterizer can solve quadratic curves in the fragment shaders, which massively reduces the geometry needed for a scene.

Also, the native rasterizer only supports MSAA, which is inferior to reference analytic area AA.