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Display: Correct max FPS limiting skew.

We were letting a percentage of too frequent flips through, causing
sometimes much higher FPS still.  Improves performance in GoW.
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unknownbrackets committed Dec 2, 2017
1 parent aa0cc67 commit b36a2c608b3fddd15bf70ef8547c6dcae8942bd4
Showing with 18 additions and 11 deletions.
  1. +18 −11 Core/HLE/sceDisplay.cpp
@@ -157,9 +157,10 @@ static float flips = 0.0f;
static int actualFlips = 0; // taking frameskip into account
static int lastActualFlips = 0;
static float actualFps = 0;
static u64 lastFlipCycles = 0;
// For the "max 60 fps" setting.
static int lastFlipsTooFrequent = 0;
static u64 lastFlipCycles = 0;
static u64 nextFlipCycles = 0;
void hleEnterVblank(u64 userdata, int cyclesLate);
void hleLeaveVblank(u64 userdata, int cyclesLate);
@@ -196,8 +197,9 @@ void __DisplayInit() {
framebuf.fmt = GE_FORMAT_8888;
framebuf.stride = 512;
memcpy(&latchedFramebuf, &framebuf, sizeof(latchedFramebuf));
lastFlipCycles = 0;
lastFlipsTooFrequent = 0;
lastFlipCycles = 0;
nextFlipCycles = 0;
wasPaused = false;
enterVblankEvent = CoreTiming::RegisterEvent("EnterVBlank", &hleEnterVblank);
@@ -876,27 +878,32 @@ u32 sceDisplaySetFramebuf(u32 topaddr, int linesize, int pixelformat, int sync)
s64 delayCycles = 0;
// Don't count transitions between display off and display on.
if (topaddr != 0 && topaddr != framebuf.topaddr && framebuf.topaddr != 0 && g_Config.iForceMaxEmulatedFPS > 0) {
// Sometimes we get a small number, there's probably no need to delay the thread for this.
// sceDisplaySetFramebuf() isn't supposed to delay threads at all. This is a hack.
const int FLIP_DELAY_CYCLES_MIN = 10;
// So let's only delay when it's more than 1ms.
const s64 FLIP_DELAY_CYCLES_MIN = usToCycles(1000);
// Some games (like Final Fantasy 4) only call this too much in spurts.
// The goal is to fix games where this would result in a consistent overhead.
const int FLIP_DELAY_MIN_FLIPS = 30;
// Since we move nextFlipCycles forward a whole frame each time, we allow it to be a little ahead.
// Otherwise it'll always be ahead if the game messes up even once.
const s64 LEEWAY_CYCLES_PER_FLIP = usToCycles(10);
u64 now = CoreTiming::GetTicks();
// 1001 to account for NTSC timing (59.94 fps.)
u64 expected = msToCycles(1001) / g_Config.iForceMaxEmulatedFPS;
u64 actual = now - lastFlipCycles;
if (actual < expected - FLIP_DELAY_CYCLES_MIN) {
s64 cyclesAhead = nextFlipCycles - now;
if (cyclesAhead > FLIP_DELAY_CYCLES_MIN) {
if (lastFlipsTooFrequent >= FLIP_DELAY_MIN_FLIPS) {
delayCycles = expected - actual;
delayCycles = cyclesAhead;
} else {
++lastFlipsTooFrequent;
}
} else {
} else if (-lastFlipsTooFrequent < FLIP_DELAY_MIN_FLIPS) {
--lastFlipsTooFrequent;
}
lastFlipCycles = CoreTiming::GetTicks();
// 1001 to account for NTSC timing (59.94 fps.)
u64 expected = msToCycles(1001) / g_Config.iForceMaxEmulatedFPS - LEEWAY_CYCLES_PER_FLIP;
lastFlipCycles = now;
nextFlipCycles = std::max(lastFlipCycles, nextFlipCycles) + expected;
}
__DisplaySetFramebuf(topaddr, linesize, pixelformat, sync);

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