Re:2D Graphics on Modern GPU (2019)
by Const-me on Monday March 15, 2021 @07:52AM
(#26464841)
> Does your approach allow for quality optimizations like sub pixel rendering for arbitrary curves?
The library only does grayscale AA for vector graphics.
Subpixel rendering implemented for text but comes with limitations: only works when text is not transformed (or transformed in specific ways, like rotated 180°, or horizontally flipped), and you need to pass background color behind the text to the API. Will only look good if the text is on solid color background, or on slow-changing gradient.
Sub pixel AA is hard for arbitrary backgrounds. I’m not sure many GPUs support the required blend states, and workarounds are slow.
> does that include drawing text as part of your transparent pass
The library only does grayscale AA for vector graphics.
Subpixel rendering implemented for text but comes with limitations: only works when text is not transformed (or transformed in specific ways, like rotated 180°, or horizontally flipped), and you need to pass background color behind the text to the API. Will only look good if the text is on solid color background, or on slow-changing gradient.
Sub pixel AA is hard for arbitrary backgrounds. I’m not sure many GPUs support the required blend states, and workarounds are slow.
> does that include drawing text as part of your transparent pass
Yes, that includes text and bitmaps. Here’s two HLSL shaders who do that, the GPU abstraction library I’ve picked recompiles the HLSL into GLSL or others on the fly: https://github.com/Const-me/Vrmac/blob/master/Vrmac/Draw/Sha... https://github.com/Const-me/Vrmac/blob/master/Vrmac/Draw/Sha... These shaders are compiled multiple times with different set of preprocessor macros, but I did test with all of them enabled at once.