Files
ppsspp/Core/FrameTiming.cpp
T
libretroadmin 9f13f0f051 Remove sleeps and timed polling from the emulation and render paths
The core no longer sleeps to pace itself: the frontend runs retro_run at
its own rate, so the frame throttle, the idle-vblank delay and the real
clock sync event (and its core option) are gone, and a stepping CPU hands
straight back instead of waiting 2 ms. Waits that polled now park on a
lock-free eventcount through Common/Thread/ParkingLot and are woken by
whoever changes the state: a paused GL emu thread, which also queues a
marker behind its last frame so pausing runs the render queue up to it
instead of polling; async I/O results; the software renderer when its
queue is full; Vulkan pipeline compiles; and debugger requests once
stepping ends. Boot joins the loader thread, cache shutdown joins its
read-ahead thread, and the slow-I/O simulation is removed.

The path browser, the HTTP and WebSocket servers, the Windows console and
the game info cache are left out of the core build. libretro/test gains
lrgltest, which drives the GL backend on a surfaceless EGL context through
every path that pauses or stops the emu thread; run.sh and the image
checks CI job run it on llvmpipe.
2026-10-08 17:58:42 +02:00

85 lines
2.8 KiB
C++

// Frame timing
//
// The frontend paces frames, so the core never waits: this only picks the present mode.
#include <algorithm>
#include "ppsspp_config.h"
#include "Common/Profiler/Profiler.h"
#include "Common/Log.h"
#include "Common/System/Display.h"
#include "Common/TimeUtil.h"
#include "Core/RetroAchievements.h"
#include "Core/CoreParameter.h"
#include "Core/Core.h"
#include "Core/System.h"
#include "Core/Config.h"
#include "Core/HW/Display.h"
#include "Core/HLE/sceNet.h"
#include "Core/FrameTiming.h"
FrameTiming g_frameTiming;
void FrameTiming::ComputePresentMode(Draw::DrawContext *draw, bool fastForward) {
if (!draw) {
// This happens in headless mode.
fastForwardSkipFlip_ = true;
presentMode_ = Draw::PresentMode::FIFO;
return;
}
_dbg_assert_(draw->GetDeviceCaps().presentModesSupported != (Draw::PresentMode)0);
if (draw->GetDeviceCaps().presentModesSupported == Draw::PresentMode::FIFO) {
// Only FIFO mode is supported (like on iOS and some GLES backends).
fastForwardSkipFlip_ = true;
presentMode_ = Draw::PresentMode::FIFO;
return;
}
// More than one present mode is supported. Use careful logic.
// The user has requested vsync off.
if (!g_Config.bVSync) {
if (draw->GetDeviceCaps().presentModesSupported & Draw::PresentMode::IMMEDIATE) {
// Use immediate mode, whether fast-forwarding or not.
presentMode_ = Draw::PresentMode::IMMEDIATE;
fastForwardSkipFlip_ = false;
return;
}
// Inconsistent state - vsync is off but immediate mode is not supported.
// We will simply force on VSync.
g_Config.bVSync = true;
}
// At this point, vsync is always on. What decides now is whether MAILBOX or IMMEDIATE is available,
// and also if we need an unsynced mode.
// OK, vsync is requested (or immediate is not available). If mailbox is supported, it works the same as IMMEDIATE above.
if (g_Config.bLowLatencyPresent) {
// Use mailbox if available. It works fine for both fast-forward and normal.
if (draw->GetDeviceCaps().presentModesSupported & Draw::PresentMode::MAILBOX) {
presentMode_ = Draw::PresentMode::MAILBOX;
fastForwardSkipFlip_ = false;
return;
}
// We could force off lowLatencyPresent here, but it's no good when changing between backends.
// So let's leave it on in the background, maybe the user just went from Vulkan to OpenGL.
}
// At this point, low-latency mode is not available, and vsync is on. We see if we can use INSTANT
// mode for fast-forwarding, or if we need to resort to frameskipping.
if (draw->GetDeviceCaps().presentInstantModeChange) {
if (fastForward) {
presentMode_ = Draw::PresentMode::IMMEDIATE;
fastForwardSkipFlip_ = false;
return;
}
}
// Finally, fallback to FIFO mode, with skip-flip in fast-forward.
presentMode_ = Draw::PresentMode::FIFO;
fastForwardSkipFlip_ = true;
}