SCUMM/FM-TOWNS: fix palette and other graphics issues

This commit should fix at least the following bugs/feature requests: #1032859, #1252088, #1055391, #1315968, #1315938, #1742106, #812891.
The FM-Towns version of Scumm games use a mixed graphics mode with 2 layers (one with 32767 colors and one with 16 colors). Among other things I have added a screen output class which emulates this  dual layer approach which allows specific hardware effects like enabling and disabling layers (e.g. in the voodoo priestess scene in MI1).

Old savegames (saved before this update) will load, but you’ll encounter palette glitches in the verb/inventory screen, since the 16 color palette for layer 2 is not contained in your savegame. This will be true at least for version 5 games. Certain scene change actions (which require the verb/inventory part to be redrawn) might correct this (e.g. try looking at the treasure map in MI1 and closing it). Version 3 games should be okay, since they use a static text palette which is never changed and which will be reset after loading a savegame.

This update requires a USE_RGB_COLORS setting for proper operation. 8 bit users will get a warning that they’ll have to expect palette glitches . Apart from that the engine in 8 bit mode should not only still work okay, but also benefit from some of the other (non palette related) improvements (e.g. bug #1032859 should be fixed even in 8 bit mode).

Japanese font drawing hasn’t been improved much yet. This will be a separate task.

svn-id: r52966

1 files changed, 34 insertions, 2 deletions

diff --git a/engines/scumm/scumm.h b/engines/scumm/scumm.h
index 1357bad8cf..d161c698c4 100644
--- a/engines/scumm/scumm.h
+++ b/engines/scumm/scumm.h
@@ -972,6 +972,7 @@ public:
 
 	Common::RenderMode _renderMode;
 	uint8 _bytesPerPixel;
+	uint8 _bytesPerPixelOutput;
 
 protected:
 	ColorCycle _colorCycle[16];	// Palette cycles
@@ -1044,6 +1045,7 @@ protected:
 	void setRoomPalette(int pal, int room);
 	void setPCEPaletteFromPtr(const byte *ptr);
 	virtual void setPaletteFromPtr(const byte *ptr, int numcolor = -1);
+
 	virtual void setPalColor(int index, int r, int g, int b);
 	void setDirtyColors(int min, int max);
 	const byte *findPalInPals(const byte *pal, int index);
@@ -1077,7 +1079,7 @@ protected:
 	// Screen rendering
 	byte *_compositeBuf;
 	byte *_herculesBuf;
-	byte *_fmtownsBuf;
+	
 	virtual void drawDirtyScreenParts();
 	void updateDirtyScreen(VirtScreenNumber slot);
 	void drawStripToScreen(VirtScreen *vs, int x, int w, int t, int b);
@@ -1221,7 +1223,7 @@ protected:
 	void restoreCharsetBg();
 	void clearCharsetMask();
 	void clearTextSurface();
-
+	
 	virtual void initCharset(int charset);
 
 	virtual void printString(int m, const byte *msg);
@@ -1397,6 +1399,36 @@ public:
 
 	// Exists both in V7 and in V72HE:
 	byte VAR_NUM_GLOBAL_OBJS;
+
+	// FM-Towns specific
+public:
+	bool towns_isRectInStringBox(int x1, int y1, int x2, int y2);
+	byte _townsPaletteFlags;
+	byte _townsCharsetColorMap[16];
+
+protected:
+	void towns_drawStripToScreen(VirtScreen *vs, int dstX, int dstY, int srcX, int srcY, int w, int h);
+#ifdef USE_RGB_COLOR
+	void towns_setPaletteFromPtr(const byte *ptr, int numcolor = -1);
+	void towns_setTextPaletteFromPtr(const byte *ptr);
+#endif
+	void towns_setupPalCycleField(int x1, int y1, int x2, int y2);
+	void towns_processPalCycleField();
+	void towns_resetPalCycleFields();
+	void towns_restoreCharsetBg();
+
+	Common::Rect _cyclRects[16];
+	int _numCyclRects;
+	
+	Common::Rect _curStringRect;
+
+	byte _townsOverrideShadowColor;	
+	byte _textPalette[48];
+	byte _townsClearLayerFlag;
+	byte _townsActiveLayerFlags;
+	static const uint8 _townsLayer2Mask[];
+
+	TownsScreen *_townsScreen;
 };
 
 } // End of namespace Scumm