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Another fun bug: all of the sprites drawn on my GUI kept flickering, but only on AMD GPUs. Never NVIDIA. I was updating a uniform buffer for the texture offset. The graphics lib missed a barrier for uniforms. Patched library, sent a PR, works now. And that was my intro to Vulkan. #gamedev #bugs

2/ The breakthrough came in figuring out what the flickering was. At first the sprites were small and the flicker looked like noise. Oddly, it even flickered within the same frame in Renderdoc. That's a giant red flag for a race condition or missing barrier, but what was it?

3/ I found out by breaking it with another bug. I made a typo that accidentally blew up the sprites to around 5x their usual size. Suddenly it was clear that it wasn't noise - it was the font atlas from the previous draw call. The texture offset in the uniform was still pointing to it - sometimes.