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Others have spoken to this, but as a general introduction I highly recommend Jasper's post "Why are 2D vector graphics so much harder than 3D?" In short, no, it

Others have spoken to this, but as a general introduction I highly recommend Jasper's post "Why are 2D vector graphics so much harder than 3D?" In short, no, it's not a solved problem. Also, I see a lot of variations of this question, but I should state this more clearly. There's been accelerated graphics in one form or another for a long time, but what I'm doing is a completely different type of thing. In my world, on the CPU you just encode the scene into a binary representation that's optimized for GPU but in many ways is like flatbuffers, and then the GPU runs a highly parallel program to render the whole thing. In previous approaches, the CPU is deeply involved in taking the scene apart and putting it back together in a form that's well suited to relatively dumb pixel pipes. Now that GPUs are really fast, that approach runs into limitations. It also depends what you're trying to do. I'm focusing here on dynamic paths (and thus font rendering), while most of the libraries optimized for UI put text into texture atlases and then use the GPU to composite quads to the final surface, something they can do well. https://blog.mecheye.net/2019/05/why-is-2d-graphics-is-harder-than-3d-graphics/ https://blog.mecheye.net/2019/05/why-is-2d-graphics-is-harde...

raks435 6y ago
Can you expound the principle of tiling mentioned in your algorithm a bit more ? The conventional mechanism is to use de-Casteljau to divide a bezier curve into triangles and then rasterize these triangles using GPU. If the curve is required to be scaled, the triangularization/tesselation is done again How is the algorithm presented in the link different ? Somehow the concept of tiling seems to imply that rasterization of the curve is done in the CPU itself. What am I missing ?
- raphlinus 6y ago
  I recommend reading the blog post series, I'm not sure I can usefully summarize the concepts in a comment reply. But very briefly, there's a flattening step (evaluated on GPU, based on de Casteljau) that converts the Bezier into a polyline (not triangles), then a tiling step that records for each tile a "command list" that contains the complete description of how to render the pixels in a tile, finally "fine rasterization" so that each workgroup reads that command list and renders 256 pixels in parallel from it. From your question, it sounds like your mental model is pretty different from how this pipeline works.
  - raks435 6y ago
    Yes, I am trying to align my mental model with yours. I read your blog post "A sort-middle architecture for 2D graphics" & "2D Graphics on Modern GPU", but still unable to grasp the fundamental guiding principles. It's not clear what are the commands that constitute each tile and whatever they are, what is the fundamental reasion which leads to the performance being better than joining the polylines of a curve to get a triangle list and having those triangle rasterized by the GPU. Any blog/article on the fundamental principles, that you would recomend

raks435 6y ago

Can you expound the principle of tiling mentioned in your algorithm a bit more ? The conventional mechanism is to use de-Casteljau to divide a bezier curve into triangles and then rasterize these triangles using GPU. If the curve is required to be scaled, the triangularization/tesselation is done again How is the algorithm presented in the link different ? Somehow the concept of tiling seems to imply that rasterization of the curve is done in the CPU itself. What am I missing ?

raphlinus 6y ago
I recommend reading the blog post series, I'm not sure I can usefully summarize the concepts in a comment reply. But very briefly, there's a flattening step (evaluated on GPU, based on de Casteljau) that converts the Bezier into a polyline (not triangles), then a tiling step that records for each tile a "command list" that contains the complete description of how to render the pixels in a tile, finally "fine rasterization" so that each workgroup reads that command list and renders 256 pixels in parallel from it. From your question, it sounds like your mental model is pretty different from how this pipeline works.
- raks435 6y ago
  Yes, I am trying to align my mental model with yours. I read your blog post "A sort-middle architecture for 2D graphics" & "2D Graphics on Modern GPU", but still unable to grasp the fundamental guiding principles. It's not clear what are the commands that constitute each tile and whatever they are, what is the fundamental reasion which leads to the performance being better than joining the polylines of a curve to get a triangle list and having those triangle rasterized by the GPU. Any blog/article on the fundamental principles, that you would recomend