On Radeon GPUs VK_IMAGE_LAYOUT_GENERAL images don't use Delta Color Compression, but SRC/DST optimal images do. Transitioning from GENERAL to SRC/DST causes a big performance hit.
As a next step we should try harder to avoid VK_IMAGE_LAYOUT_GENERAL.
Signed-off-by: Stefan Dösinger stefan@codeweavers.com
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This is an updated version of Merge Request #4, with fixes for the regression in World of Tanks I noticed.
This improves Rocket League from 50fps to 67fps when it is GPU limited. Using VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL instead of GENERAL further improves it to 80 fps. Switching from COLOR_ATTACHMENT_OPTIMAL to SRC/DST optimal seems cheap (it just stays compressed), but first we need logic to transition BIND_RENDER_TARGET | BIND_SHADER_RESOURCE textures between COLOR_ATTACHMENT_OPTIMAL and SHADER_READ_ONLY_OPTIMAL.