SCI: Add a new configuration option for SQ4 CD, "silver_cursors"

This allows the user to choose the alternate set of silver mouse cursors
that is available in the game resources of the game, instead of the
original golden ones

README

@@ -2083,6 +2083,11 @@ King's Quest VI Windows adds the following non-standard keyword:
                                 Windows version, upscaled to match the rest of
                                 the upscaled graphics
 
+Space Quest IV CD adds the following non-standard keyword:
+
+     silver_cursors    bool     If true, an alternate set of silver mouse cursors
+	                            is used instead of the original golden ones
+
 Simon the Sorcerer 1 and 2 add the following non-standard keywords:
 
     music_mute         bool     If true, music is muted

engines/sci/graphics/cursor.cpp

@@ -59,10 +59,16 @@ GfxCursor::GfxCursor(ResourceManager *resMan, GfxPalette *palette, GfxScreen *sc
 	_zoomColor = 0;
 	_zoomMultiplier = 0;
 	_cursorSurface = 0;
+
 	if (g_sci && g_sci->getGameId() == GID_KQ6 && g_sci->getPlatform() == Common::kPlatformWindows)
 		_useOriginalKQ6WinCursors = ConfMan.getBool("windows_cursors");
 	else
 		_useOriginalKQ6WinCursors = false;
+
+	if (g_sci && g_sci->getGameId() == GID_SQ4 && getSciVersion() == SCI_VERSION_1_1)
+		_useSilverSQ4CDCursors = ConfMan.getBool("silver_cursors");
+	else
+		_useSilverSQ4CDCursors = false;
 }
 
 GfxCursor::~GfxCursor() {
@@ -206,6 +212,26 @@ void GfxCursor::kernelSetView(GuiResourceId viewNum, int loopNum, int celNum, Co
 		return;
 	}
 
+	// Use the alternate silver cursors in SQ4 CD, if requested
+	if (_useSilverSQ4CDCursors) {
+		switch(viewNum) {
+		case 850:
+		case 852:
+		case 854:
+		case 856:
+			celNum = 3;
+			break;
+		case 851:
+		case 853:
+		case 855:
+		case 999:
+			celNum = 2;
+			break;
+		default:
+			break;
+		}
+	}
+
 	if (!_cachedCursors.contains(viewNum))
 		_cachedCursors[viewNum] = new GfxView(_resMan, _screen, _palette, viewNum);
 

engines/sci/graphics/cursor.h

@@ -113,13 +113,18 @@ private:
 
 	bool _isVisible;
 
-	// KQ6 Windows has different black and white cursors. If this is
-	// true (set from the sci_originalkq6wincursors ini setting), then
-	// we use these, and don't scale them by 2x like the rest of the
-	// graphics, like SSCI did. These look very ugly, which is why
-	// they aren't enabled by default.
+	// KQ6 Windows has different black and white cursors. If this is true (set
+	// from the windows_cursors ini setting), then we use these and don't scale
+	// them by 2x like the rest of the graphics, like SSCI did. These look very
+	// ugly, which is why they aren't enabled by default.
 	bool _useOriginalKQ6WinCursors;
 
+	// The CD version of SQ4 contains a complete set of silver mouse cursors.
+	// If this is true (set from the silver_cursors ini setting), then we use
+	// these instead and replace the game's gold cursors with their silver
+	// equivalents.
+	bool _useSilverSQ4CDCursors;
+
 	// Mac versions of games use a remap list to remap their cursors
 	Common::Array<uint16> _macCursorRemap;
 };

engines/sci/sci.cpp

@@ -194,6 +194,7 @@ Common::Error SciEngine::run() {
 	ConfMan.registerDefault("sci_originalsaveload", "false");
 	ConfMan.registerDefault("native_fb01", "false");
 	ConfMan.registerDefault("windows_cursors", "false");	// Windows cursors for KQ6 Windows
+	ConfMan.registerDefault("silver_cursors", "false");	// Silver cursors for SQ4 CD
 
 	_resMan = new ResourceManager();
 	assert(_resMan);