Workaround for sin/cos issue in GTA on Mac (and maybe others) #16928
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| @@ -29,6 +29,13 @@ | |||
| #define V(i) (currentMIPS->v[voffset[i]]) | |||
| #define VI(i) (currentMIPS->vi[voffset[i]]) | |||
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| // Flushes the angle to 0 if exponent smaller than this in vfpu_sin/vfpu_cos/vfpu_sincos. | |||
| // Was measured to be around 0x68, but GTA on Mac is somehow super sensitive | |||
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Well, it's not "about zero", the PSP doesn't return any non-zero value with an exponent below 0x68 (based on an exhaustive analysis of all possible input values that don't wrap.) I'm not arguing with this change, though, as clearly macOS/iOS are returning values with lower exponents than that for values for which the PSP returns an exponent >= 0x68.
-[Unknown]
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Fixes #15149
Turns out the game is hyper sensitive to the shape of the sin curve, so while we tried making its precision a bit more accurate to the hardware by reducing the precision, this resulted in something going slightly over one threshold or another due to the sin curve shape not being bit identical on all platforms. This just works around it by lowering the threshold for when we flush the angle to zero.