n64: fix VI bug causing spinloop#2300
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LukeUsher merged 1 commit intoares-emulator:masterfrom Nov 27, 2025
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VI_H_TOTAL is defined as the number of cycles per scanline *minus 1*. We forgot to add that 1 back. Besides the minor inaccuracy in timing, we could hit a race condition during initial VI config: if the Ares VI thread ran when the display was turned on (VI_CTRL configured) but VI_H_TOTAL wasn't already configured (and thus defaulted to 0), the thread would spinloop forever because it would step by 0 cycles. While fixing this, I also noticed that I wasn't properly taking into account leap timings because of a typo; this means that PAL timings were very slightly off. Fixes ares-emulator#2293
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VI_H_TOTAL is defined as the number of cycles per scanline minus 1. We forgot to add that 1 back. Besides the minor inaccuracy in timing, we could hit a race condition during initial VI config: if the Ares VI thread ran when the display was turned on (VI_CTRL configured) but VI_H_TOTAL wasn't already configured (and thus defaulted to 0), the thread would spinloop forever because it would step by 0 cycles.
While fixing this, I also noticed that I wasn't properly taking into account leap timings because of a typo; this means that PAL timings were very slightly off.
Fixes #2293