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xezonxezon
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refactor(gameengine): Move game time related code into new FramePacer class (#1688)
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-465
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35 files changed

+390
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‎Core/GameEngine/CMakeLists.txt‎

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@@ -39,6 +39,7 @@ set(GAMEENGINE_SRC
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# Include/Common/Errors.h
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Include/Common/file.h
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Include/Common/FileSystem.h
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Include/Common/FramePacer.h
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Include/Common/FrameRateLimit.h
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# Include/Common/FunctionLexicon.h
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Include/Common/GameAudio.h
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# Source/Common/DamageFX.cpp
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# Source/Common/Dict.cpp
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# Source/Common/DiscreteCircle.cpp
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Source/Common/FramePacer.cpp
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Source/Common/FrameRateLimit.cpp
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# Source/Common/GameEngine.cpp
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# Source/Common/GameLOD.cpp

‎Core/GameEngine/Include/Common/FramePacer.h‎

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/*
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** Command & Conquer Generals Zero Hour(tm)
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** Copyright 2025 Electronic Arts Inc.
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**
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** This program is free software: you can redistribute it and/or modify
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** it under the terms of the GNU General Public License as published by
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** the Free Software Foundation, either version 3 of the License, or
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** (at your option) any later version.
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**
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** This program is distributed in the hope that it will be useful,
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** but WITHOUT ANY WARRANTY; without even the implied warranty of
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** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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** GNU General Public License for more details.
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**
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** You should have received a copy of the GNU General Public License
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** along with this program. If not, see <http://www.gnu.org/licenses/>.
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*/
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#pragma once
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#include "Common/FrameRateLimit.h"
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class FramePacer
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{
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public:
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typedef UnsignedInt LogicTimeQueryFlags;
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enum LogicTimeQueryFlags_ CPP_11(: LogicTimeQueryFlags)
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{
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IgnoreFrozenTime = 1<<0, ///< Ignore frozen time for the query
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IgnoreHaltedGame = 1<<1, ///< Ignore halted game for the query
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};
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FramePacer();
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~FramePacer();
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void update(); ///< Signal that the app/render update is done and wait for the fps limit if applicable.
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void setFramesPerSecondLimit( Int fps ); ///< Set the max update fps.
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Int getFramesPerSecondLimit() const; ///< Get the max update fps.
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Real getUpdateTime() const; ///< Get the last update delta time in seconds.
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Real getUpdateFps() const; ///< Get the last update fps.
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void setTimeFrozen(Bool frozen); ///< Set time frozen. Allows scripted camera movement.
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void setGameHalted(Bool halted); ///< Set game halted. Does not allow scripted camera movement.
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Bool isTimeFrozen() const;
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Bool isGameHalted() const;
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void setLogicTimeScaleFps( Int fps ); ///< Set the logic time scale fps and therefore scale the simulation time. Is capped by the max render fps and does not apply to network matches.
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Int getLogicTimeScaleFps() const; ///< Get the raw logic time scale fps value.
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void enableLogicTimeScale( Bool enable ); ///< Enable the logic time scale setup. If disabled, the simulation time scale is bound to the render frame time or network update time.
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Bool isLogicTimeScaleEnabled() const; ///< Check whether the logic time scale setup is enabled.
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Int getActualLogicTimeScaleFps(LogicTimeQueryFlags flags = 0) const; ///< Get the real logic time scale fps, depending on the max render fps, network state and enabled state.
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Real getActualLogicTimeScaleRatio(LogicTimeQueryFlags flags = 0) const; ///< Get the real logic time scale ratio, depending on the max render fps, network state and enabled state.
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Real getActualLogicTimeScaleOverFpsRatio(LogicTimeQueryFlags flags = 0) const; ///< Get the real logic time scale over render fps ratio, used to scale down steps in render updates to match logic updates.
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Real getLogicTimeStepSeconds(LogicTimeQueryFlags flags = 0) const; ///< Get the logic time step in seconds
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Real getLogicTimeStepMilliseconds(LogicTimeQueryFlags flags = 0) const; ///< Get the logic time step in milliseconds
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protected:
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FrameRateLimit m_frameRateLimit;
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Int m_maxFPS; ///< Maximum frames per second for rendering
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Int m_logicTimeScaleFPS; ///< Maximum frames per second for logic time scale
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Real m_updateTime; ///< Last update delta time in seconds
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Bool m_enableLogicTimeScale;
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Bool m_isTimeFrozen;
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Bool m_isGameHalted;
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};
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extern FramePacer* TheFramePacer;

‎Core/GameEngine/Source/Common/FramePacer.cpp‎

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/*
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** Command & Conquer Generals Zero Hour(tm)
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** Copyright 2025 Electronic Arts Inc.
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**
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** This program is free software: you can redistribute it and/or modify
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** it under the terms of the GNU General Public License as published by
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** the Free Software Foundation, either version 3 of the License, or
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** (at your option) any later version.
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**
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** This program is distributed in the hope that it will be useful,
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** but WITHOUT ANY WARRANTY; without even the implied warranty of
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** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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** GNU General Public License for more details.
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**
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** You should have received a copy of the GNU General Public License
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** along with this program. If not, see <http://www.gnu.org/licenses/>.
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*/
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#include "PreRTS.h"
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#include "Common/FramePacer.h"
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#include "GameClient/View.h"
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#include "GameLogic/GameLogic.h"
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#include "GameLogic/ScriptEngine.h"
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#include "GameNetwork/NetworkDefs.h"
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#include "GameNetwork/NetworkInterface.h"
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FramePacer* TheFramePacer = NULL;
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FramePacer::FramePacer()
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{
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// Set the time slice size to 1 ms.
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timeBeginPeriod(1);
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m_maxFPS = BaseFps;
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m_logicTimeScaleFPS = LOGICFRAMES_PER_SECOND;
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m_updateTime = 1.0f / BaseFps; // initialized to something to avoid division by zero on first use
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m_enableLogicTimeScale = FALSE;
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m_isTimeFrozen = FALSE;
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m_isGameHalted = FALSE;
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}
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FramePacer::~FramePacer()
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{
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// Restore the previous time slice for Windows.
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timeEndPeriod(1);
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}
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void FramePacer::update()
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{
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Bool allowFpsLimit = TheTacticalView->getTimeMultiplier()<=1 && !TheScriptEngine->isTimeFast();
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// I'm disabling this in debug because many people need alt-tab capability. If you happen to be
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// doing performance tuning, please just change this on your local system. -MDC
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#if defined(RTS_DEBUG)
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if (allowFpsLimit)
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::Sleep(1); // give everyone else a tiny time slice.
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#endif
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#if defined(_ALLOW_DEBUG_CHEATS_IN_RELEASE)
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allowFpsLimit &= !(!TheGameLogic->isGamePaused() && TheGlobalData->m_TiVOFastMode);
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#else //always allow this cheat key if we're in a replay game.
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allowFpsLimit &= !(!TheGameLogic->isGamePaused() && TheGlobalData->m_TiVOFastMode && TheGameLogic->isInReplayGame());
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#endif
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// TheSuperHackers @bugfix xezon 05/08/2025 Re-implements the frame rate limiter
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// with higher resolution counters to cap the frame rate more accurately to the desired limit.
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allowFpsLimit &= TheGlobalData->m_useFpsLimit;
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const UnsignedInt maxFps = allowFpsLimit ? getFramesPerSecondLimit() : RenderFpsPreset::UncappedFpsValue;
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m_updateTime = m_frameRateLimit.wait(maxFps);
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}
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void FramePacer::setFramesPerSecondLimit( Int fps )
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{
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DEBUG_LOG(("FramePacer::setFramesPerSecondLimit() - setting max fps to %d (TheGlobalData->m_useFpsLimit == %d)", fps, TheGlobalData->m_useFpsLimit));
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m_maxFPS = fps;
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}
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Int FramePacer::getFramesPerSecondLimit() const
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{
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return m_maxFPS;
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}
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Real FramePacer::getUpdateTime() const
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{
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return m_updateTime;
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}
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Real FramePacer::getUpdateFps() const
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{
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return 1.0f / m_updateTime;
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}
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void FramePacer::setTimeFrozen(Bool frozen)
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{
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m_isTimeFrozen = frozen;
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}
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void FramePacer::setGameHalted(Bool halted)
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{
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m_isGameHalted = halted;
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}
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Bool FramePacer::isTimeFrozen() const
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{
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return m_isTimeFrozen;
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}
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Bool FramePacer::isGameHalted() const
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{
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return m_isGameHalted;
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}
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void FramePacer::setLogicTimeScaleFps( Int fps )
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{
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m_logicTimeScaleFPS = fps;
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}
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Int FramePacer::getLogicTimeScaleFps() const
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{
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return m_logicTimeScaleFPS;
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}
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void FramePacer::enableLogicTimeScale( Bool enable )
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{
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m_enableLogicTimeScale = enable;
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}
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Bool FramePacer::isLogicTimeScaleEnabled() const
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{
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return m_enableLogicTimeScale;
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}
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Int FramePacer::getActualLogicTimeScaleFps(LogicTimeQueryFlags flags) const
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{
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if (m_isTimeFrozen && (flags & IgnoreFrozenTime) == 0)
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{
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return 0;
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}
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if (m_isGameHalted && (flags & IgnoreHaltedGame) == 0)
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{
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return 0;
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}
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if (TheNetwork != NULL)
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{
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return TheNetwork->getFrameRate();
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}
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if (isLogicTimeScaleEnabled())
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{
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return min(getLogicTimeScaleFps(), getFramesPerSecondLimit());
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}
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return getFramesPerSecondLimit();
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}
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Real FramePacer::getActualLogicTimeScaleRatio(LogicTimeQueryFlags flags) const
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{
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return (Real)getActualLogicTimeScaleFps(flags) / LOGICFRAMES_PER_SECONDS_REAL;
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}
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Real FramePacer::getActualLogicTimeScaleOverFpsRatio(LogicTimeQueryFlags flags) const
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{
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// TheSuperHackers @info Clamps ratio to min 1, because the logic
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// frame rate is currently capped by the render frame rate.
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return min(1.0f, (Real)getActualLogicTimeScaleFps(flags) / getUpdateFps());
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}
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Real FramePacer::getLogicTimeStepSeconds(LogicTimeQueryFlags flags) const
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{
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return SECONDS_PER_LOGICFRAME_REAL * getActualLogicTimeScaleOverFpsRatio(flags);
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}
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Real FramePacer::getLogicTimeStepMilliseconds(LogicTimeQueryFlags flags) const
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{
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return MSEC_PER_LOGICFRAME_REAL * getActualLogicTimeScaleOverFpsRatio(flags);
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}

‎Generals/Code/GameEngine/Include/Common/GameEngine.h‎

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@@ -55,15 +55,6 @@ class ParticleSystemManager;
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class GameEngine : public SubsystemInterface
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{
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public:
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typedef UnsignedInt LogicTimeQueryFlags;
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enum LogicTimeQueryFlags_ CPP_11(: LogicTimeQueryFlags)
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{
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IgnoreFrozenTime = 1<<0, // Ignore frozen time for the query
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IgnoreHaltedGame = 1<<1, // Ignore halted game for the query
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};
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public:
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GameEngine( void );
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virtual void execute( void ); /**< The "main loop" of the game engine.
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It will not return until the game exits. */
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virtual void setFramesPerSecondLimit( Int fps ); ///< Set the max render and engine update fps.
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virtual Int getFramesPerSecondLimit( void ); ///< Get the max render and engine update fps.
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Real getUpdateTime(); ///< Get the last engine update delta time in seconds.
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Real getUpdateFps(); ///< Get the last engine update fps.
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static Bool isTimeFrozen(); ///< Returns true if a script has frozen time.
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static Bool isGameHalted(); ///< Returns true if the game is paused or the network is stalling.
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virtual void setLogicTimeScaleFps( Int fps ); ///< Set the logic time scale fps and therefore scale the simulation time. Is capped by the max render fps and does not apply to network matches.
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virtual Int getLogicTimeScaleFps(); ///< Get the raw logic time scale fps value.
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virtual void enableLogicTimeScale( Bool enable ); ///< Enable the logic time scale setup. If disabled, the simulation time scale is bound to the render frame time or network update time.
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virtual Bool isLogicTimeScaleEnabled(); ///< Check whether the logic time scale setup is enabled.
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Int getActualLogicTimeScaleFps(LogicTimeQueryFlags flags = 0); ///< Get the real logic time scale fps, depending on the max render fps, network state and enabled state.
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Real getActualLogicTimeScaleRatio(LogicTimeQueryFlags flags = 0); ///< Get the real logic time scale ratio, depending on the max render fps, network state and enabled state.
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Real getActualLogicTimeScaleOverFpsRatio(LogicTimeQueryFlags flags = 0); ///< Get the real logic time scale over render fps ratio, used to scale down steps in render updates to match logic updates.
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Real getLogicTimeStepSeconds(LogicTimeQueryFlags flags = 0); ///< Get the logic time step in seconds
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Real getLogicTimeStepMilliseconds(LogicTimeQueryFlags flags = 0); ///< Get the logic time step in milliseconds
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virtual void setQuitting( Bool quitting ); ///< set quitting status
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virtual Bool getQuitting(void); ///< is app getting ready to quit.
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virtual ParticleSystemManager* createParticleSystemManager( void ) = 0;
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virtual AudioManager *createAudioManager( void ) = 0; ///< Factory for Audio Manager
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Int m_maxFPS; ///< Maximum frames per second for rendering
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Int m_logicTimeScaleFPS; ///< Maximum frames per second for logic time scale
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Real m_updateTime; ///< Last engine update delta time in seconds
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Real m_logicTimeAccumulator; ///< Frame time accumulated towards submitting a new logic frame
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Bool m_quitting; ///< true when we need to quit the game
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Bool m_isActive; ///< app has OS focus.
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Bool m_enableLogicTimeScale;
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Bool m_isTimeFrozen;
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Bool m_isGameHalted;
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};
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inline void GameEngine::setQuitting( Bool quitting ) { m_quitting = quitting; }

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