BACKENDS: Do not send mouse events to games occurring outside the game draw rect

5 files changed, 63 insertions, 27 deletions

diff --git a/backends/events/sdl/sdl-events.cpp b/backends/events/sdl/sdl-events.cpp
index db4aa21ef1..6f34420674 100644
--- a/backends/events/sdl/sdl-events.cpp
+++ b/backends/events/sdl/sdl-events.cpp
@@ -169,13 +169,15 @@ int SdlEventSource::mapKey(SDLKey sdlKey, SDLMod mod, Uint16 unicode) {
 	}
 }
 
-void SdlEventSource::processMouseEvent(Common::Event &event, int x, int y) {
+bool SdlEventSource::processMouseEvent(Common::Event &event, int x, int y) {
 	event.mouse.x = x;
 	event.mouse.y = y;
 
 	if (_graphicsManager) {
-		_graphicsManager->notifyMousePosition(event.mouse);
+		return _graphicsManager->notifyMousePosition(event.mouse);
 	}
+
+	return true;
 }
 
 bool SdlEventSource::handleKbdMouse(Common::Event &event) {
@@ -307,8 +309,7 @@ bool SdlEventSource::handleKbdMouse(Common::Event &event) {
 
 			if (_km.x != oldKmX || _km.y != oldKmY) {
 				event.type = Common::EVENT_MOUSEMOVE;
-				processMouseEvent(event, _km.x / MULTIPLIER, _km.y / MULTIPLIER);
-				return true;
+				return processMouseEvent(event, _km.x / MULTIPLIER, _km.y / MULTIPLIER);
 			}
 		}
 	}
@@ -548,7 +549,9 @@ bool SdlEventSource::dispatchSDLEvent(SDL_Event &ev, Common::Event &event) {
 		// with a mouse wheel event. However, SDL2 does not supply
 		// these, thus we use whatever we got last time. It seems
 		// these are always stored in _km.x, _km.y.
-		processMouseEvent(event, _km.x / MULTIPLIER, _km.y / MULTIPLIER);
+		if (!processMouseEvent(event, _km.x / MULTIPLIER, _km.y / MULTIPLIER)) {
+			return false;
+		}
 		if (yDir < 0) {
 			event.type = Common::EVENT_WHEELDOWN;
 			return true;
@@ -739,12 +742,12 @@ bool SdlEventSource::handleKeyUp(SDL_Event &ev, Common::Event &event) {
 
 bool SdlEventSource::handleMouseMotion(SDL_Event &ev, Common::Event &event) {
 	event.type = Common::EVENT_MOUSEMOVE;
-	processMouseEvent(event, ev.motion.x, ev.motion.y);
+
 	// update KbdMouse
 	_km.x = ev.motion.x * MULTIPLIER;
 	_km.y = ev.motion.y * MULTIPLIER;
 
-	return true;
+	return processMouseEvent(event, ev.motion.x, ev.motion.y);
 }
 
 bool SdlEventSource::handleMouseButtonDown(SDL_Event &ev, Common::Event &event) {
@@ -765,12 +768,11 @@ bool SdlEventSource::handleMouseButtonDown(SDL_Event &ev, Common::Event &event)
 	else
 		return false;
 
-	processMouseEvent(event, ev.button.x, ev.button.y);
 	// update KbdMouse
 	_km.x = ev.button.x * MULTIPLIER;
 	_km.y = ev.button.y * MULTIPLIER;
 
-	return true;
+	return processMouseEvent(event, ev.button.x, ev.button.y);
 }
 
 bool SdlEventSource::handleMouseButtonUp(SDL_Event &ev, Common::Event &event) {
@@ -784,21 +786,21 @@ bool SdlEventSource::handleMouseButtonUp(SDL_Event &ev, Common::Event &event) {
 #endif
 	else
 		return false;
-	processMouseEvent(event, ev.button.x, ev.button.y);
+
 	// update KbdMouse
 	_km.x = ev.button.x * MULTIPLIER;
 	_km.y = ev.button.y * MULTIPLIER;
 
-	return true;
+	return processMouseEvent(event, ev.button.x, ev.button.y);
 }
 
 bool SdlEventSource::handleJoyButtonDown(SDL_Event &ev, Common::Event &event) {
 	if (ev.jbutton.button == JOY_BUT_LMOUSE) {
 		event.type = Common::EVENT_LBUTTONDOWN;
-		processMouseEvent(event, _km.x / MULTIPLIER, _km.y / MULTIPLIER);
+		return processMouseEvent(event, _km.x / MULTIPLIER, _km.y / MULTIPLIER);
 	} else if (ev.jbutton.button == JOY_BUT_RMOUSE) {
 		event.type = Common::EVENT_RBUTTONDOWN;
-		processMouseEvent(event, _km.x / MULTIPLIER, _km.y / MULTIPLIER);
+		return processMouseEvent(event, _km.x / MULTIPLIER, _km.y / MULTIPLIER);
 	} else {
 		event.type = Common::EVENT_KEYDOWN;
 		switch (ev.jbutton.button) {
@@ -819,17 +821,17 @@ bool SdlEventSource::handleJoyButtonDown(SDL_Event &ev, Common::Event &event) {
 			event.kbd.ascii = mapKey(SDLK_F5, (SDLMod)ev.key.keysym.mod, 0);
 			break;
 		}
+		return true;
 	}
-	return true;
 }
 
 bool SdlEventSource::handleJoyButtonUp(SDL_Event &ev, Common::Event &event) {
 	if (ev.jbutton.button == JOY_BUT_LMOUSE) {
 		event.type = Common::EVENT_LBUTTONUP;
-		processMouseEvent(event, _km.x / MULTIPLIER, _km.y / MULTIPLIER);
+		return processMouseEvent(event, _km.x / MULTIPLIER, _km.y / MULTIPLIER);
 	} else if (ev.jbutton.button == JOY_BUT_RMOUSE) {
 		event.type = Common::EVENT_RBUTTONUP;
-		processMouseEvent(event, _km.x / MULTIPLIER, _km.y / MULTIPLIER);
+		return processMouseEvent(event, _km.x / MULTIPLIER, _km.y / MULTIPLIER);
 	} else {
 		event.type = Common::EVENT_KEYUP;
 		switch (ev.jbutton.button) {
@@ -850,8 +852,8 @@ bool SdlEventSource::handleJoyButtonUp(SDL_Event &ev, Common::Event &event) {
 			event.kbd.ascii = mapKey(SDLK_F5, (SDLMod)ev.key.keysym.mod, 0);
 			break;
 		}
+		return true;
 	}
-	return true;
 }
 
 bool SdlEventSource::handleJoyAxisMotion(SDL_Event &ev, Common::Event &event) {
diff --git a/backends/events/sdl/sdl-events.h b/backends/events/sdl/sdl-events.h
index cf445e9e2c..1d701f5ecf 100644
--- a/backends/events/sdl/sdl-events.h
+++ b/backends/events/sdl/sdl-events.h
@@ -117,7 +117,7 @@ protected:
 	 * Assigns the mouse coords to the mouse event. Furthermore notify the
 	 * graphics manager about the position change.
 	 */
-	virtual void processMouseEvent(Common::Event &event, int x, int y);
+	virtual bool processMouseEvent(Common::Event &event, int x, int y);
 
 	/**
 	 * Remaps key events. This allows platforms to configure
diff --git a/backends/graphics/sdl/sdl-graphics.cpp b/backends/graphics/sdl/sdl-graphics.cpp
index 6ce0bc7bac..e6699df1cd 100644
--- a/backends/graphics/sdl/sdl-graphics.cpp
+++ b/backends/graphics/sdl/sdl-graphics.cpp
@@ -169,22 +169,47 @@ bool SdlGraphicsManager::showMouse(const bool visible) {
 	return WindowedGraphicsManager::showMouse(visible);
 }
 
-void SdlGraphicsManager::notifyMousePosition(Common::Point &mouse) {
+bool SdlGraphicsManager::notifyMousePosition(Common::Point &mouse) {
 	int showCursor = SDL_DISABLE;
-	if (!_activeArea.drawRect.contains(mouse)) {
+	bool valid = true;
+	if (_activeArea.drawRect.contains(mouse)) {
+		_cursorLastInActiveArea = true;
+	} else {
 		mouse.x = CLIP<int>(mouse.x, _activeArea.drawRect.left, _activeArea.drawRect.right - 1);
 		mouse.y = CLIP<int>(mouse.y, _activeArea.drawRect.top, _activeArea.drawRect.bottom - 1);
 
-		if (_window->mouseIsGrabbed()) {
+		if (_window->mouseIsGrabbed() ||
+			// Keep the mouse inside the game area during dragging to prevent an
+			// event mismatch where the mouseup event gets lost because it is
+			// performed outside of the game area
+			(_cursorLastInActiveArea && SDL_GetMouseState(nullptr, nullptr) != 0)) {
 			setSystemMousePosition(mouse.x, mouse.y);
-		} else if (_cursorVisible) {
-			showCursor = SDL_ENABLE;
+		} else {
+			// Allow the in-game mouse to get a final movement event to the edge
+			// of the window if the mouse was moved out of the game area
+			if (_cursorLastInActiveArea) {
+				_cursorLastInActiveArea = false;
+			} else if (_cursorVisible) {
+				// Keep sending events to the game if the cursor is invisible,
+				// since otherwise if a game lets you skip a cutscene by
+				// clicking and the user moved the mouse outside the active
+				// area, the clicks wouldn't do anything, which would be
+				// confusing
+				valid = false;
+			}
+
+			if (_cursorVisible) {
+				showCursor = SDL_ENABLE;
+			}
 		}
 	}
 
 	SDL_ShowCursor(showCursor);
-	setMousePosition(mouse.x, mouse.y);
-	mouse = convertWindowToVirtual(mouse.x, mouse.y);
+	if (valid) {
+		setMousePosition(mouse.x, mouse.y);
+		mouse = convertWindowToVirtual(mouse.x, mouse.y);
+	}
+	return valid;
 }
 
 void SdlGraphicsManager::handleResizeImpl(const int width, const int height) {
diff --git a/backends/graphics/sdl/sdl-graphics.h b/backends/graphics/sdl/sdl-graphics.h
index 772bc88637..993a1c3db6 100644
--- a/backends/graphics/sdl/sdl-graphics.h
+++ b/backends/graphics/sdl/sdl-graphics.h
@@ -84,8 +84,10 @@ public:
 	 *
 	 * @param mouse The mouse position in window coordinates, which must be
 	 * converted synchronously to virtual coordinates.
+	 * @returns true if the mouse was in a valid position for the game and
+	 * should cause the event to be sent to the game.
 	 */
-	virtual void notifyMousePosition(Common::Point &mouse);
+	virtual bool notifyMousePosition(Common::Point &mouse);
 
 	virtual bool showMouse(const bool visible) override;
 
diff --git a/backends/graphics/windowed.h b/backends/graphics/windowed.h
index 52bb96c2cf..1d4958c9d6 100644
--- a/backends/graphics/windowed.h
+++ b/backends/graphics/windowed.h
@@ -39,7 +39,8 @@ public:
 		_cursorVisible(false),
 		_cursorX(0),
 		_cursorY(0),
-		_cursorNeedsRedraw(false) {}
+		_cursorNeedsRedraw(false),
+		_cursorLastInActiveArea(true) {}
 
 	virtual void showOverlay() override {
 		if (_overlayVisible)
@@ -304,6 +305,12 @@ protected:
 	bool _cursorNeedsRedraw;
 
 	/**
+	 * Whether the last position of the system cursor was within the active area
+	 * of the window.
+	 */
+	bool _cursorLastInActiveArea;
+
+	/**
 	 * The position of the mouse cursor, in window coordinates.
 	 */
 	int _cursorX, _cursorY;