tweak(scrolling): Prevent far camera jumps when scrolling while the game stalls (#1661)

xezon · web-flow · commit 8a264723346d · 2025-11-07T18:57:56.000+01:00
diff --git a/Core/GameEngine/Include/Common/FramePacer.h b/Core/GameEngine/Include/Common/FramePacer.h
@@ -49,6 +49,7 @@ class FramePacer
 
 	Real getUpdateTime() const; ///< Get the last update delta time in seconds.
 	Real getUpdateFps() const; ///< Get the last update fps.
+	Real getBaseOverUpdateFpsRatio(Real minUpdateFps = 5.0f); ///< Get the last engine base over update fps ratio. Used to scale user inputs to a frame rate independent speed.
 
 	void setTimeFrozen(Bool frozen); ///< Set time frozen. Allows scripted camera movement.
 	void setGameHalted(Bool halted); ///< Set game halted. Does not allow scripted camera movement.
diff --git a/Core/GameEngine/Source/Common/FramePacer.cpp b/Core/GameEngine/Source/Common/FramePacer.cpp
@@ -118,6 +118,13 @@ Real FramePacer::getUpdateFps()  const
 	return 1.0f / m_updateTime;
 }
 
+Real FramePacer::getBaseOverUpdateFpsRatio(Real minUpdateFps)
+{
+	// Update fps is floored to default 5 fps, 200 ms.
+	// Useful to prevent insane ratios on frame spikes/stalls.
+	return (Real)BaseFps / std::max(getUpdateFps(), minUpdateFps);
+}
+
 void FramePacer::setTimeFrozen(Bool frozen)
 {
 	m_isTimeFrozen = frozen;
diff --git a/Generals/Code/GameEngine/Source/GameClient/InGameUI.cpp b/Generals/Code/GameEngine/Source/GameClient/InGameUI.cpp
@@ -23,7 +23,7 @@
 ////////////////////////////////////////////////////////////////////////////////
 
 // InGameUI.cpp ///////////////////////////////////////////////////////////////////////////////////
-// Implementation of in-game user interface singleton inteface
+// Implementation of in-game user interface singleton
 // Author: Michael S. Booth, March 2001
 ///////////////////////////////////////////////////////////////////////////////////////////////////
 
@@ -1939,7 +1939,7 @@ void InGameUI::update( void )
 	if (m_cameraRotatingLeft || m_cameraRotatingRight || m_cameraZoomingIn || m_cameraZoomingOut)
 	{
 		// TheSuperHackers @tweak The camera rotation and zoom are now decoupled from the render update.
-		const Real fpsRatio = (Real)BaseFps / TheFramePacer->getUpdateFps();
+		const Real fpsRatio = TheFramePacer->getBaseOverUpdateFpsRatio();
 		const Real rotateAngle = TheGlobalData->m_keyboardCameraRotateSpeed * fpsRatio;
 		const Real zoomHeight = (Real)View::ZoomHeightPerSecond * fpsRatio;
 
diff --git a/Generals/Code/GameEngine/Source/GameClient/MessageStream/LookAtXlat.cpp b/Generals/Code/GameEngine/Source/GameClient/MessageStream/LookAtXlat.cpp
@@ -30,6 +30,7 @@
 
 #include "Common/FramePacer.h"
 #include "Common/GameType.h"
+#include "Common/GameEngine.h"
 #include "Common/MessageStream.h"
 #include "Common/Player.h"
 #include "Common/PlayerList.h"
@@ -440,7 +441,7 @@ GameMessageDisposition LookAtTranslator::translateGameMessage(const GameMessage
 			{
 
 				// TheSuperHackers @bugfix Mauller 07/06/2025 The camera scrolling is now decoupled from the render update.
-				const Real fpsRatio = (Real)BaseFps / TheFramePacer->getUpdateFps();
+				const Real fpsRatio = TheFramePacer->getBaseOverUpdateFpsRatio();
 
 				switch (m_scrollType)
 				{
diff --git a/Generals/Code/GameEngineDevice/Source/W3DDevice/GameClient/W3DView.cpp b/Generals/Code/GameEngineDevice/Source/W3DDevice/GameClient/W3DView.cpp
@@ -1207,7 +1207,7 @@ void W3DView::update(void)
 			// if scrolling, only adjust if we're too close or too far
 			if (m_scrollAmount.length() < m_scrollAmountCutoff || (m_currentHeightAboveGround < m_minHeightAboveGround) || (TheGlobalData->m_enforceMaxCameraHeight && m_currentHeightAboveGround > m_maxHeightAboveGround))
 			{
-				const Real fpsRatio = (Real)BaseFps / TheFramePacer->getUpdateFps();
+				const Real fpsRatio = TheFramePacer->getBaseOverUpdateFpsRatio();
 				const Real zoomAdj = (desiredZoom - m_zoom) * TheGlobalData->m_cameraAdjustSpeed * fpsRatio;
 				if (fabs(zoomAdj) >= 0.0001f)	// only do positive
 				{
@@ -1219,7 +1219,7 @@ void W3DView::update(void)
 		else if (!didScriptedMovement)
 		{
 			// we're not scrolling; settle toward desired height above ground
-			const Real fpsRatio = (Real)BaseFps / TheFramePacer->getUpdateFps();
+			const Real fpsRatio = TheFramePacer->getBaseOverUpdateFpsRatio();
 			const Real zoomAdj = (m_zoom - desiredZoom) * TheGlobalData->m_cameraAdjustSpeed * fpsRatio;
 			if (fabs(zoomAdj) >= 0.0001f)
 			{
diff --git a/GeneralsMD/Code/GameEngine/Source/GameClient/InGameUI.cpp b/GeneralsMD/Code/GameEngine/Source/GameClient/InGameUI.cpp
@@ -23,7 +23,7 @@
 ////////////////////////////////////////////////////////////////////////////////
 
 // InGameUI.cpp ///////////////////////////////////////////////////////////////////////////////////
-// Implementation of in-game user interface singleton inteface
+// Implementation of in-game user interface singleton
 // Author: Michael S. Booth, March 2001
 ///////////////////////////////////////////////////////////////////////////////////////////////////
 
@@ -1995,7 +1995,7 @@ void InGameUI::update( void )
 	if (m_cameraRotatingLeft || m_cameraRotatingRight || m_cameraZoomingIn || m_cameraZoomingOut)
 	{
 		// TheSuperHackers @tweak The camera rotation and zoom are now decoupled from the render update.
-		const Real fpsRatio = (Real)BaseFps / TheFramePacer->getUpdateFps();
+		const Real fpsRatio = TheFramePacer->getBaseOverUpdateFpsRatio();
 		const Real rotateAngle = TheGlobalData->m_keyboardCameraRotateSpeed * fpsRatio;
 		const Real zoomHeight = (Real)View::ZoomHeightPerSecond * fpsRatio;
 
diff --git a/GeneralsMD/Code/GameEngine/Source/GameClient/MessageStream/LookAtXlat.cpp b/GeneralsMD/Code/GameEngine/Source/GameClient/MessageStream/LookAtXlat.cpp
@@ -30,6 +30,7 @@
 
 #include "Common/FramePacer.h"
 #include "Common/GameType.h"
+#include "Common/GameEngine.h"
 #include "Common/MessageStream.h"
 #include "Common/Player.h"
 #include "Common/PlayerList.h"
@@ -439,7 +440,7 @@ GameMessageDisposition LookAtTranslator::translateGameMessage(const GameMessage
 			{
 
 				// TheSuperHackers @bugfix Mauller 07/06/2025 The camera scrolling is now decoupled from the render update.
-				const Real fpsRatio = (Real)BaseFps / TheFramePacer->getUpdateFps();
+				const Real fpsRatio = TheFramePacer->getBaseOverUpdateFpsRatio();
 
 				switch (m_scrollType)
 				{
diff --git a/GeneralsMD/Code/GameEngineDevice/Source/W3DDevice/GameClient/W3DView.cpp b/GeneralsMD/Code/GameEngineDevice/Source/W3DDevice/GameClient/W3DView.cpp
@@ -1356,7 +1356,7 @@ void W3DView::update(void)
 			// if scrolling, only adjust if we're too close or too far
 			if (m_scrollAmount.length() < m_scrollAmountCutoff || (m_currentHeightAboveGround < m_minHeightAboveGround) || (TheGlobalData->m_enforceMaxCameraHeight && m_currentHeightAboveGround > m_maxHeightAboveGround))
 			{
-				const Real fpsRatio = (Real)BaseFps / TheFramePacer->getUpdateFps();
+				const Real fpsRatio = TheFramePacer->getBaseOverUpdateFpsRatio();
 				const Real zoomAdj = (desiredZoom - m_zoom) * TheGlobalData->m_cameraAdjustSpeed * fpsRatio;
 				if (fabs(zoomAdj) >= 0.0001f)	// only do positive
 				{
@@ -1368,7 +1368,7 @@ void W3DView::update(void)
 		else if (!didScriptedMovement)
 		{
 			// we're not scrolling; settle toward desired height above ground
-			const Real fpsRatio = (Real)BaseFps / TheFramePacer->getUpdateFps();
+			const Real fpsRatio = TheFramePacer->getBaseOverUpdateFpsRatio();
 			const Real zoomAdj = (m_zoom - desiredZoom) * TheGlobalData->m_cameraAdjustSpeed * fpsRatio;
 			if (fabs(zoomAdj) >= 0.0001f)
 			{

Original file line number	Diff line number	Diff line change
`@@ -118,6 +118,13 @@ Real FramePacer::getUpdateFps() const`
`118`	`118`	`return 1.0f / m_updateTime;`
`119`	`119`	`}`
`120`	`120`
	`121`	`+Real FramePacer::getBaseOverUpdateFpsRatio(Real minUpdateFps)`
	`122`	`+{`
	`123`	`+ // Update fps is floored to default 5 fps, 200 ms.`
	`124`	`+ // Useful to prevent insane ratios on frame spikes/stalls.`
	`125`	`+ return (Real)BaseFps / std::max(getUpdateFps(), minUpdateFps);`
	`126`	`+}`
	`127`	`+`
`121`	`128`	`void FramePacer::setTimeFrozen(Bool frozen)`
`122`	`129`	`{`
`123`	`130`	`m_isTimeFrozen = frozen;`
Original file line number	Diff line number	Diff line change
`@@ -30,6 +30,7 @@`
`30`	`30`
`31`	`31`	`#include "Common/FramePacer.h"`
`32`	`32`	`#include "Common/GameType.h"`
	`33`	`+#include "Common/GameEngine.h"`
`33`	`34`	`#include "Common/MessageStream.h"`
`34`	`35`	`#include "Common/Player.h"`
`35`	`36`	`#include "Common/PlayerList.h"`
`@@ -440,7 +441,7 @@ GameMessageDisposition LookAtTranslator::translateGameMessage(const GameMessage`
`440`	`441`	`{`
`441`	`442`
`442`	`443`	`// TheSuperHackers @bugfix Mauller 07/06/2025 The camera scrolling is now decoupled from the render update.`
`443`		`- const Real fpsRatio = (Real)BaseFps / TheFramePacer->getUpdateFps();`
	`444`	`+ const Real fpsRatio = TheFramePacer->getBaseOverUpdateFpsRatio();`
`444`	`445`
`445`	`446`	`switch (m_scrollType)`
`446`	`447`	`{`
Original file line number	Diff line number	Diff line change
`@@ -1207,7 +1207,7 @@ void W3DView::update(void)`
`1207`	`1207`	`// if scrolling, only adjust if we're too close or too far`
`1208`	`1208`	`if (m_scrollAmount.length() < m_scrollAmountCutoff \|\| (m_currentHeightAboveGround < m_minHeightAboveGround) \|\| (TheGlobalData->m_enforceMaxCameraHeight && m_currentHeightAboveGround > m_maxHeightAboveGround))`
`1209`	`1209`	`{`
`1210`		`- const Real fpsRatio = (Real)BaseFps / TheFramePacer->getUpdateFps();`
	`1210`	`+ const Real fpsRatio = TheFramePacer->getBaseOverUpdateFpsRatio();`
`1211`	`1211`	`const Real zoomAdj = (desiredZoom - m_zoom) * TheGlobalData->m_cameraAdjustSpeed * fpsRatio;`
`1212`	`1212`	`if (fabs(zoomAdj) >= 0.0001f) // only do positive`
`1213`	`1213`	`{`
`@@ -1219,7 +1219,7 @@ void W3DView::update(void)`
`1219`	`1219`	`else if (!didScriptedMovement)`
`1220`	`1220`	`{`
`1221`	`1221`	`// we're not scrolling; settle toward desired height above ground`
`1222`		`- const Real fpsRatio = (Real)BaseFps / TheFramePacer->getUpdateFps();`
	`1222`	`+ const Real fpsRatio = TheFramePacer->getBaseOverUpdateFpsRatio();`
`1223`	`1223`	`const Real zoomAdj = (m_zoom - desiredZoom) * TheGlobalData->m_cameraAdjustSpeed * fpsRatio;`
`1224`	`1224`	`if (fabs(zoomAdj) >= 0.0001f)`
`1225`	`1225`	`{`
Original file line number	Diff line number	Diff line change
`@@ -1356,7 +1356,7 @@ void W3DView::update(void)`
`1356`	`1356`	`// if scrolling, only adjust if we're too close or too far`
`1357`	`1357`	`if (m_scrollAmount.length() < m_scrollAmountCutoff \|\| (m_currentHeightAboveGround < m_minHeightAboveGround) \|\| (TheGlobalData->m_enforceMaxCameraHeight && m_currentHeightAboveGround > m_maxHeightAboveGround))`
`1358`	`1358`	`{`
`1359`		`- const Real fpsRatio = (Real)BaseFps / TheFramePacer->getUpdateFps();`
	`1359`	`+ const Real fpsRatio = TheFramePacer->getBaseOverUpdateFpsRatio();`
`1360`	`1360`	`const Real zoomAdj = (desiredZoom - m_zoom) * TheGlobalData->m_cameraAdjustSpeed * fpsRatio;`
`1361`	`1361`	`if (fabs(zoomAdj) >= 0.0001f) // only do positive`
`1362`	`1362`	`{`
`@@ -1368,7 +1368,7 @@ void W3DView::update(void)`
`1368`	`1368`	`else if (!didScriptedMovement)`
`1369`	`1369`	`{`
`1370`	`1370`	`// we're not scrolling; settle toward desired height above ground`
`1371`		`- const Real fpsRatio = (Real)BaseFps / TheFramePacer->getUpdateFps();`
	`1371`	`+ const Real fpsRatio = TheFramePacer->getBaseOverUpdateFpsRatio();`
`1372`	`1372`	`const Real zoomAdj = (m_zoom - desiredZoom) * TheGlobalData->m_cameraAdjustSpeed * fpsRatio;`
`1373`	`1373`	`if (fabs(zoomAdj) >= 0.0001f)`
`1374`	`1374`	`{`