GPU/Pitfalls: Difference between revisions
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=== TEXUNIT1 Corruption and Instability === | |||
If an L4-formatted texture (or likely any 4-bit texture format) located within VRAM is bound to TEXUNIT1, the PICA can become unstable, usually freezing after a seemingly random amount of time. If that texture is 8x16 or larger, the GPU will also display corrupt visuals until the console is rebooted; this will even persist in other software. Unbinding the texture makes the console stable again, but doesn't fix the visuals, though the severity of the corruption is slightly reduced because the exact results also depend on the texture data. Notably, this does not seem to occur with other TEXUNITs or with textures located in FCRAM. This could use more investigation. | |||
Writer's Note: I struggled for days to reproduce this. I happened across it in a real application, and swapping between L4 and L8 affected the issue with 100% consistency. I then went to make this write-up months later and made a test program to reproduce the bug, which worked as expected. Like a doofus I rewrote the program a bit to test a bit more thoroughly, somehow caused the bug to stop occurring, and haven't been able to reproduce it since. Needs further investigation. | |||
== Shaders == | == Shaders == | ||