John Lindgren 2ec08b38d8 [RFC] vulkan: compensate alpha to better match perceptual blend intent ... The Vulkan renderer performs alpha blending in linear RGB space, which preserves hue better than blending sRGB-encoded values directly (as the gles and pixman renderers do), but unfortunately tends to give a too-bright result when blending dark and light colors. (In desktop usage, this especially affects dark, semi-transparent tooltips, which appear significantly more transparent than expected, affecting readability if light text underneath shows through.) This is a novel (I think) approach to compensating for this effect by adjusting the alpha value of the source texture - basically the result is that dark semi-transparent pixels are made a little more opaque, while light semi-transparent pixels are made a little more transparent. Alpha values of 0 and 1 are unchanged. I am somewhat new to science of color blending (Björn Ottosson's page, "How software gets color wrong" is very enlightening) but I think this approach makes at least a little bit of sense theoretically, and the result seems to me subjectively to be an improvement. Analysis from an expert on the subject would be greatly appreciated. v2: compensate alpha in solid color conversions also v3: un-premultiply average value for solid color conversion		2024-12-14 11:55:03 -05:00
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common.vert	render/vulkan: Optimize vertex shader	2021-11-23 15:46:24 +00:00
meson.build	render/vulkan: allow rendering to non-8-bit buffers	2023-05-12 15:09:02 +00:00
output.frag	render/vulkan: add lut3d output shader option	2024-04-26 17:17:36 +00:00
quad.frag	render/vulkan: add Vulkan renderer	2021-10-18 11:51:13 +02:00
texture.frag	[RFC] vulkan: compensate alpha to better match perceptual blend intent	2024-12-14 11:55:03 -05:00