Yes, the multithreading on the GPU picks up good performance in OpenGL and the extensions for compositing make a huge difference due to drawing all the vectors

Yes, the multithreading on the GPU picks up good performance in OpenGL and the extensions for compositing make a huge difference due to drawing all the vectors on the screen quickly. NanoVG uses a single header file for a lot of operations so it's hard to beat where performance is concerned it mostly talks directly to the GPU. I think if precompiling shaders and using indirect draw calls with Vulkan can reduce the glDrawArray/Elements bottleneck then it will have succeeded at delivering better performance. There is a "depends how you use it" and "how you measure performance" issue comparing any and all GPU based vector libraries. Also, the data structures supporting the paths will affect things a lot since there is a ton of allocating and freeing memory going on. Comparing the two you could potentially run hundreds of different tests just to get the answer to this question.