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I wouldn't strictly say that. Even with quadratic curves, you still have a serial process of parsing a shape to determine interior vs. exterior. This is true of

I wouldn't strictly say that. Even with quadratic curves, you still have a serial process of parsing a shape to determine interior vs. exterior. This is true of any non-convex polygon, not just those with curves. You have to solve that sort somehow, whether it be through linear search (e.g. Slug), through geometry simplification (e.g. Loop-Blinn, triangulation), through signed area tricks (e.g. red book, style stencil-and-cover), or through brute force (e.g. SDFs). Eliminating cubics eliminates some trickier problems, but I don't think it fully solves the issues.

slimsag 5y ago
Yep, you probably read my comment before I edited and clarified, but you also need to eliminate overlapping geometry. Basically just build your graphics around non-overlapping convex and concave quadratic curves represented as triangles. The trick is in building tooling that makes that a pleasant experience (and do any required reductions of more complex shapes -> isolated quadratic curves at tool time, not at render time.) Existing approaches try to fit what we have (SVGs, complex polygons) onto what GPUs can do. This approach tries to take what GPUs _can do_ and make that competitive with what we have (SVGs, etc.)
- megameter 5y ago
  In working with existing graphics tools to make drawings, something I've come to realize is that overlap is crucial to the workflow: it's easier to draw the line you want by overshooting and erasing than it is to get it precisely drafted. Likewise it's much easier to paint within a stencil mask than it is to stay within the lines freehand. To me, that suggests the main distinction between source and output formats comes from how/whether they go about decimating the "erasure" data, since the final result produces much more complex non-overlapped paths. The attractiveness of the Bezier usually isn't in the initial definition of a shape - it just happens to be great at reproduction of multiple curves cut and spliced together. So it has the feel of a premature optimization that probably should be reconsidered in making more ergonomic tooling.

slimsag 5y ago

Yep, you probably read my comment before I edited and clarified, but you also need to eliminate overlapping geometry. Basically just build your graphics around non-overlapping convex and concave quadratic curves represented as triangles. The trick is in building tooling that makes that a pleasant experience (and do any required reductions of more complex shapes -> isolated quadratic curves at tool time, not at render time.) Existing approaches try to fit what we have (SVGs, complex polygons) onto what GPUs can do. This approach tries to take what GPUs _can do_ and make that competitive with what we have (SVGs, etc.)

megameter 5y ago
In working with existing graphics tools to make drawings, something I've come to realize is that overlap is crucial to the workflow: it's easier to draw the line you want by overshooting and erasing than it is to get it precisely drafted. Likewise it's much easier to paint within a stencil mask than it is to stay within the lines freehand. To me, that suggests the main distinction between source and output formats comes from how/whether they go about decimating the "erasure" data, since the final result produces much more complex non-overlapped paths. The attractiveness of the Bezier usually isn't in the initial definition of a shape - it just happens to be great at reproduction of multiple curves cut and spliced together. So it has the feel of a premature optimization that probably should be reconsidered in making more ergonomic tooling.