[XCX] Port FPS++ to 60FPS mod, dynamic FPS limits and fixed cutscenes

Fixes #475.

Thanks to @MetrosexualGarbodor for the generous bounty!

Author: Crementif

src/XenobladeChroniclesX/Mods/60FPS/patch_60fps.asm

@@ -0,0 +1,98 @@
+[XCX_FPS++_Cutscene]
+moduleMatches = 0x218F6E07, 0xF882D5CF, 0x30B6E091, 0x7672271D ; 1.0.0E, 1.0.1E, 1.0.2U, 1.0.2J
+
+.origin = codecave
+
+forceCutsceneLimit:
+.int 0
+
+_useCutsceneLimit:
+li r10, 1
+lis r9, forceCutsceneLimit@ha
+stw r10, forceCutsceneLimit@l(r9)
+
+lfs f11, -0x303C(r8)
+blr
+
+_resetCutsceneLimit:
+li r10, 0
+lis r9, forceCutsceneLimit@ha
+stw r10, forceCutsceneLimit@l(r9)
+b _restoreRegisters
+
+cutsceneFloatConv:
+cutsceneFloatConvHa:
+.uint 0
+cutsceneFloatConvL:
+.uint 0
+
+
+; Check if a cutscene is ongoing with a set FPS limit
+_waitTillCutsceneLimit:
+li r10, $cutsceneFPSLimit
+cmpwi r10, 1
+bne _calculateFPS
+lis r10, forceCutsceneLimit@ha
+lwz r10, forceCutsceneLimit@l(r10)
+cmpwi r10, 1
+bne _calculateFPS
+
+; If a cutscene FPS limit is set, lower FPS
+_lowerCutsceneFPS:
+lis r10, const_30@ha
+lfs f12, const_30@l(r10)
+
+; Calculate how many ticks a frame has to take to render at the given FPS limit
+lis r10, const_1@ha
+lfs f7, const_1@l(r10)
+fdivs f12, f7, f12
+lis r10, timerTickSpeed@ha
+lfs f7, timerTickSpeed@l(r10)
+fmuls f12, f7, f12
+
+; Subtract the time that it took for the actual frame to render and make sure that it's not negative (which means a frame already took longer to render then the FPS limit)
+fsubs f12, f12, f10
+lis r10, const_0.0@ha
+lfs f7, const_0.0@l(r10)
+fcmpu cr0, f7, f12
+ble .+0x8
+fmr f12, f7
+
+; Convert the remaining ticks that should be spend idling to an integer (but it requires storing it in memory)
+fctiwz f12, f12
+lis r10, cutsceneFloatConvHa@ha
+stfd f12, cutsceneFloatConvHa@l(r10)
+
+# ; Load the converted integer ticks and sleep for the given amount of time
+mr r10, r4
+lis r9, cutsceneFloatConvL@ha
+lwz r4, cutsceneFloatConvL@l(r9)
+mr r11, r3
+# li r3, 0
+lis r9, cutsceneFloatConvHa@ha
+lwz r3, cutsceneFloatConvHa@l(r9)
+mflr r9
+bl import.coreinit.OSSleepTicks
+mtlr r9
+mr r3, r11
+mr r4, r10
+
+_reacquireTime:
+mr r11, r3
+mr r10, r4
+mflr r9
+bl import.coreinit.OSGetSystemTime
+mtlr r9
+
+lis r9, prevFrameTime_Up32Bit@ha
+stw r3, prevFrameTime_Up32Bit@l(r9)
+lis r9, prevFrameTime_Low32Bit@ha
+stw r4, prevFrameTime_Low32Bit@l(r9)
+mr r3, r11
+mr r4, r10
+
+; Directly set the game speed to 30FPS when cutscenes are active
+lis r10, const_30@ha
+lfs f10, const_30@l(r10)
+
+b _setGameSpeed