gfx.h

/*****************************************************************************\
     Snes9x - Portable Super Nintendo Entertainment System (TM) emulator.
                This file is licensed under the Snes9x License.
   For further information, consult the LICENSE file in the root directory.
\*****************************************************************************/

#ifndef _GFX_H_
#define _GFX_H_

#include "port.h"

struct SGFX
{
	uint16	*Screen;
	uint16	*SubScreen;
	uint8	*ZBuffer;
	uint8	*SubZBuffer;
	uint32	Pitch;
	uint32	ScreenSize;
	uint16	*S;
	uint8	*DB;
	uint16	*ZERO;
	uint32	RealPPL;			// true PPL of Screen buffer
	uint32	PPL;				// number of pixels on each of Screen buffer
	uint32	LinesPerTile;		// number of lines in 1 tile (4 or 8 due to interlace)
	uint16	*ScreenColors;		// screen colors for rendering main
	uint16	*RealScreenColors;	// screen colors, ignoring color window clipping
	uint8	Z1;					// depth for comparison
	uint8	Z2;					// depth to save
	uint32	FixedColour;
	uint8	DoInterlace;
	uint8	InterlaceFrame;
	uint32	StartY;
	uint32	EndY;
	bool8	ClipColors;
	uint8	OBJWidths[128];
	uint8	OBJVisibleTiles[128];

	struct ClipData	*Clip;

	struct
	{
		uint8	RTOFlags;
		int16	Tiles;

		struct
		{
			int8	Sprite;
			uint8	Line;
		}	OBJ[32];
	}	OBJLines[SNES_HEIGHT_EXTENDED];

	void	(*DrawBackdropMath) (uint32, uint32, uint32);
	void	(*DrawBackdropNomath) (uint32, uint32, uint32);
	void	(*DrawTileMath) (uint32, uint32, uint32, uint32);
	void	(*DrawTileNomath) (uint32, uint32, uint32, uint32);
	void	(*DrawClippedTileMath) (uint32, uint32, uint32, uint32, uint32, uint32);
	void	(*DrawClippedTileNomath) (uint32, uint32, uint32, uint32, uint32, uint32);
	void	(*DrawMosaicPixelMath) (uint32, uint32, uint32, uint32, uint32, uint32);
	void	(*DrawMosaicPixelNomath) (uint32, uint32, uint32, uint32, uint32, uint32);
	void	(*DrawMode7BG1Math) (uint32, uint32, int);
	void	(*DrawMode7BG1Nomath) (uint32, uint32, int);
	void	(*DrawMode7BG2Math) (uint32, uint32, int);
	void	(*DrawMode7BG2Nomath) (uint32, uint32, int);

	const char	*InfoString;
	uint32	InfoStringTimeout;
	char	FrameDisplayString[256];
};

struct SBG
{
	uint8	(*ConvertTile) (uint8 *, uint32, uint32);
	uint8	(*ConvertTileFlip) (uint8 *, uint32, uint32);

	uint32	TileSizeH;
	uint32	TileSizeV;
	uint32	OffsetSizeH;
	uint32	OffsetSizeV;
	uint32	TileShift;
	uint32	TileAddress;
	uint32	NameSelect;
	uint32	SCBase;

	uint32	StartPalette;
	uint32	PaletteShift;
	uint32	PaletteMask;
	uint8	EnableMath;
	uint8	InterlaceLine;

	uint8	*Buffer;
	uint8	*BufferFlip;
	uint8	*Buffered;
	uint8	*BufferedFlip;
	bool8	DirectColourMode;
};

struct SLineData
{
	struct
	{
		uint16	VOffset;
		uint16	HOffset;
	}	BG[4];
};

struct SLineMatrixData
{
	short	MatrixA;
	short	MatrixB;
	short	MatrixC;
	short	MatrixD;
	short	CentreX;
	short	CentreY;
	short	M7HOFS;
	short	M7VOFS;
};

extern uint16		BlackColourMap[256];
extern uint16		DirectColourMaps[8][256];
extern uint8		mul_brightness[16][32];
extern uint8		brightness_cap[64];
extern struct SBG	BG;
extern struct SGFX	GFX;

#define H_FLIP		0x4000
#define V_FLIP		0x8000
#define BLANK_TILE	2

#define COLOR_ADD1_2(C1, C2) \
	((((((C1) & RGB_REMOVE_LOW_BITS_MASK) + \
	((C2) & RGB_REMOVE_LOW_BITS_MASK)) >> 1) + \
	((C1) & (C2) & RGB_LOW_BITS_MASK)) | ALPHA_BITS_MASK)
#define COLOR_ADD_BRIGHTNESS1_2 COLOR_ADD1_2

inline uint16 COLOR_ADD_BRIGHTNESS(uint16 C1, uint16 C2)
{
    return ((brightness_cap[ (C1 >> RED_SHIFT_BITS)           +  (C2 >> RED_SHIFT_BITS)          ] << RED_SHIFT_BITS)   |
            (brightness_cap[((C1 >> GREEN_SHIFT_BITS) & 0x1f) + ((C2 >> GREEN_SHIFT_BITS) & 0x1f)] << GREEN_SHIFT_BITS) |
// Proper 15->16bit color conversion moves the high bit of green into the low bit.
#if GREEN_SHIFT_BITS == 6
           ((brightness_cap[((C1 >> 6) & 0x1f) + ((C2 >> 6) & 0x1f)] & 0x10) << 1) |
#endif
            (brightness_cap[ (C1                      & 0x1f) +  (C2                      & 0x1f)]      ));
}

inline uint16 COLOR_ADD(uint16 C1, uint16 C2)
{
	const int RED_MASK = 0x1F << RED_SHIFT_BITS;
	const int GREEN_MASK = 0x1F << GREEN_SHIFT_BITS;
	const int BLUE_MASK = 0x1F;

	int rb = C1 & (RED_MASK | BLUE_MASK);
	rb += C2 & (RED_MASK | BLUE_MASK);
	int rbcarry = rb & ((0x20 << RED_SHIFT_BITS) | (0x20 << 0));
	int g = (C1 & (GREEN_MASK)) + (C2 & (GREEN_MASK));
	int rgbsaturate = (((g & (0x20 << GREEN_SHIFT_BITS)) | rbcarry) >> 5) * 0x1f;
	uint16 retval = (rb & (RED_MASK | BLUE_MASK)) | (g & GREEN_MASK) | rgbsaturate;
#if GREEN_SHIFT_BITS == 6
	retval |= (retval & 0x0400) >> 5;
#endif
	return retval;
}


#define COLOR_SUB1_2(C1, C2) \
	GFX.ZERO[(((C1) | RGB_HI_BITS_MASKx2) - \
	((C2) & RGB_REMOVE_LOW_BITS_MASK)) >> 1]

inline uint16 COLOR_SUB (uint16 C1, uint16 C2)
{
	int rb1 = (C1 & (THIRD_COLOR_MASK | FIRST_COLOR_MASK)) | ((0x20 << 0) | (0x20 << RED_SHIFT_BITS));
	int rb2 = C2 & (THIRD_COLOR_MASK | FIRST_COLOR_MASK);
	int rb = rb1 - rb2;
	int rbcarry = rb & ((0x20 << RED_SHIFT_BITS) | (0x20 << 0));
	int g = ((C1 & (SECOND_COLOR_MASK)) | (0x20 << GREEN_SHIFT_BITS)) - (C2 & (SECOND_COLOR_MASK));
	int rgbsaturate = (((g & (0x20 << GREEN_SHIFT_BITS)) | rbcarry) >> 5) * 0x1f;
	uint16 retval = ((rb & (THIRD_COLOR_MASK | FIRST_COLOR_MASK)) | (g & SECOND_COLOR_MASK)) & rgbsaturate;
#if GREEN_SHIFT_BITS == 6
	retval |= (retval & 0x0400) >> 5;
#endif
	return retval;
}

void S9xStartScreenRefresh (void);
void S9xEndScreenRefresh (void);
void S9xBuildDirectColourMaps (void);
void RenderLine (uint8);
void S9xComputeClipWindows (void);
void S9xDisplayChar (uint16 *, uint8);
void S9xGraphicsScreenResize (void);
// called automatically unless Settings.AutoDisplayMessages is false
void S9xDisplayMessages (uint16 *, int, int, int, int);

// external port interface which must be implemented or initialised for each port
bool8 S9xGraphicsInit (void);
void S9xGraphicsDeinit (void);
bool8 S9xInitUpdate (void);
bool8 S9xDeinitUpdate (int, int);
bool8 S9xContinueUpdate (int, int);
void S9xReRefresh (void);
void S9xSetPalette (void);
void S9xSyncSpeed (void);

// called instead of S9xDisplayString if set to non-NULL
extern void (*S9xCustomDisplayString) (const char *, int, int, bool, int type);

#endif