Codechange: Allow video drivers to handle the cursor themselves.

src/gfx.cpp

@@ -1348,6 +1348,9 @@ void ScreenSizeChanged()
 
 void UndrawMouseCursor()
 {
+	/* Don't undraw mouse cursor if it is handled by the video driver. */
+	if (VideoDriver::GetInstance()->UseSystemCursor()) return;
+
 	/* Don't undraw the mouse cursor if the screen is not ready */
 	if (_screen.dst_ptr == nullptr) return;
 
@@ -1361,6 +1364,9 @@ void UndrawMouseCursor()
 
 void DrawMouseCursor()
 {
+	/* Don't draw mouse cursor if it is handled by the video driver. */
+	if (VideoDriver::GetInstance()->UseSystemCursor()) return;
+
 	/* Don't draw the mouse cursor if the screen is not ready */
 	if (_screen.dst_ptr == nullptr) return;
 

src/spritecache.cpp

@@ -17,6 +17,7 @@
 #include "blitter/factory.hpp"
 #include "core/math_func.hpp"
 #include "core/mem_func.hpp"
+#include "video/video_driver.hpp"
 
 #include "table/sprites.h"
 #include "table/strings.h"
@@ -977,6 +978,8 @@ void GfxClearSpriteCache()
 		SpriteCache *sc = GetSpriteCache(i);
 		if (sc->type != ST_RECOLOUR && sc->ptr != nullptr) DeleteEntryFromSpriteCache(i);
 	}
+
+	VideoDriver::GetInstance()->ClearSystemSprites();
 }
 
 /* static */ ReusableBuffer<SpriteLoader::CommonPixel> SpriteLoader::Sprite::buffer[ZOOM_LVL_COUNT];

src/video/video_driver.hpp

@@ -85,6 +85,20 @@ public:
 		return true;
 	}
 
+	/**
+	 * Get whether the mouse cursor is drawn by the video driver.
+	 * @return True if cursor drawing is done by the video driver.
+	 */
+	virtual bool UseSystemCursor()
+	{
+		return false;
+	}
+
+	/**
+	 * Clear all cached sprites.
+	 */
+	virtual void ClearSystemSprites() {}
+
 	/**
 	 * Whether the driver has a graphical user interface with the end user.
 	 * Or in other words, whether we should spawn a thread for world generation