scummvm/engines/sci/graphics/palette32.h

/* ScummVM - Graphic Adventure Engine
 *
 * ScummVM is the legal property of its developers, whose names
 * are too numerous to list here. Please refer to the COPYRIGHT
 * file distributed with this source distribution.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 */

#ifndef SCI_GRAPHICS_PALETTE32_H
#define SCI_GRAPHICS_PALETTE32_H

#include "sci/graphics/palette.h"

namespace Sci {
enum PalCyclerDirection {
	PalCycleBackward = 0,
	PalCycleForward = 1
};

struct PalCycler {
	/**
	 * The color index of the palette cycler. This value is effectively used as the ID for the
	 * cycler.
	 */
	uint8 fromColor;

	/**
	 * The number of palette slots which are cycled by the palette cycler.
	 */
	uint16 numColorsToCycle;

	/**
	 * The position of the cursor in its cycle.
	 */
	uint8 currentCycle;

	/**
	 * The direction of the cycler.
	 */
	PalCyclerDirection direction;

	/**
	 * The cycle tick at the last time the cycler’s currentCycle was updated.
	 * 795 days of game time ought to be enough for everyone? :)
	 */
	uint32 lastUpdateTick;

	/**
	 * The amount of time in ticks each cycle should take to complete. In other words,
	 * the higher the delay, the slower the cycle animation. If delay is 0, the cycler
	 * does not automatically cycle and needs to be pumped manually with DoCycle.
	 */
	int16 delay;

	/**
	 * The number of times this cycler has been paused.
	 */
	uint16 numTimesPaused;
};

class GfxPalette32 : public GfxPalette {
public:
	GfxPalette32(ResourceManager *resMan, GfxScreen *screen);
	~GfxPalette32();

private:
	// NOTE: currentPalette in SCI engine is called _sysPalette
	// here.

	/**
	 * The palette revision version. Increments once per game
	 * loop that changes the source palette. TODO: Possibly
	 * other areas also change _version, double-check once it
	 * is all implemented.
	 */
	uint32 _version;

	/**
	 * Whether or not the palette manager version was updated
	 * during this loop.
	 */
	bool _versionUpdated;

	/**
	 * The unmodified source palette loaded by kPalette. Additional
	 * palette entries may be mixed into the source palette by
	 * CelObj objects, which contain their own palettes.
	 */
	Palette _sourcePalette;

	/**
	 * The palette to be used when the hardware is next updated.
	 * On update, _nextPalette is transferred to _sysPalette.
	 */
	Palette _nextPalette;

	bool createPaletteFromResourceInternal(const GuiResourceId paletteId, Palette *const out) const;
	Palette getPaletteFromResourceInternal(const GuiResourceId paletteId) const;

public:
	virtual void saveLoadWithSerializer(Common::Serializer &s) override;
	const Palette *getNextPalette() const;

	bool kernelSetFromResource(GuiResourceId resourceId, bool force) override;
	int16 kernelFindColor(uint16 r, uint16 g, uint16 b) override;
	void set(Palette *newPalette, bool force, bool forceRealMerge = false) override;
	int16 matchColor(const byte matchRed, const byte matchGreen, const byte matchBlue, const int defaultDifference, int &lastCalculatedDifference, const bool *const matchTable);

	/**
	 * Submits a palette to display. Entries marked as “used” in the
	 * submitted palette are merged into the existing entries of
	 * _sourcePalette.
	 */
	void submit(Palette &palette);

	bool updateForFrame();
	void updateFFrame();
	void updateHardware();
	void applyAll();

#pragma mark -
#pragma mark color look-up
private:
	/**
	 * An optional lookup table used to remap RGB565 colors to a palette
	 * index. Used by Phantasmagoria 2 in 8-bit color environments.
	 */
	byte *_clutTable;

public:
	bool loadClut(uint16 clutId);
	byte matchClutColor(uint16 color);
	void unloadClut();

#pragma mark -
#pragma mark Varying
private:
	/**
	 * An optional palette used to describe the source colors used
	 * in a palette vary operation. If this palette is not specified,
	 * sourcePalette is used instead.
	 */
	Palette *_varyStartPalette;

	/**
	 * An optional palette used to describe the target colors used
	 * in a palette vary operation.
	 */
	Palette *_varyTargetPalette;

	/**
	 * The minimum palette index that has been varied from the
	 * source palette. 0–255
	 */
	uint8 _varyFromColor;

	/**
	 * The maximum palette index that is has been varied from the
	 * source palette. 0-255
	 */
	uint8 _varyToColor;

	/**
	 * The tick at the last time the palette vary was updated.
	 */
	uint32 _varyLastTick;

	/**
	 * The amount of time to elapse, in ticks, between each cycle
	 * of a palette vary animation.
	 */
	int _varyTime;

	/**
	 * The direction of change: -1, 0, or 1.
	 */
	int16 _varyDirection;

	/**
	 * The amount, in percent, that the vary color is currently
	 * blended into the source color.
	 */
	int16 _varyPercent;

	/**
	 * The target amount that a vary color will be blended into
	 * the source color.
	 */
	int16 _varyTargetPercent;

	/**
	 * The number of time palette varying has been paused.
	 */
	uint16 _varyNumTimesPaused;

public:
	void kernelPalVarySet(const GuiResourceId paletteId, const int16 percent, const int time, const int16 fromColor, const int16 toColor);
	void kernelPalVaryMergeTarget(const GuiResourceId paletteId);
	void kernelPalVarySetTarget(const GuiResourceId paletteId);
	void kernelPalVarySetStart(const GuiResourceId paletteId);
	void kernelPalVaryMergeStart(const GuiResourceId paletteId);
	virtual void kernelPalVaryPause(bool pause) override;

	void setVary(const Palette *const targetPalette, const int16 percent, const int time, const int16 fromColor, const int16 toColor);
	void setVaryPercent(const int16 percent, const int time, const int16 fromColor, const int16 fromColorAlternate);
	int16 getVaryPercent() const;
	void varyOff();
	void mergeTarget(const Palette *const palette);
	void varyPause();
	void varyOn();
	void setVaryTime(const int time);
	void setTarget(const Palette *const palette);
	void setStart(const Palette *const palette);
	void mergeStart(const Palette *const palette);
	void setVaryTimeInternal(const int16 percent, const int time);
	void applyVary();

#pragma mark -
#pragma mark Cycling
private:
	// SQ6 defines 10 cyclers
	PalCycler *_cyclers[10];

	/**
	 * The cycle map is used to detect overlapping cyclers.
	 * According to SCI engine code, when two cyclers overlap,
	 * a fatal error has occurred and the engine will display
	 * an error and then exit.
	 */
	bool _cycleMap[256];
	inline void clearCycleMap(uint16 fromColor, uint16 numColorsToClear);
	inline void setCycleMap(uint16 fromColor, uint16 numColorsToClear);
	inline PalCycler *getCycler(uint16 fromColor);

public:
	void setCycle(const uint8 fromColor, const uint8 toColor, const int16 direction, const int16 delay);
	void doCycle(const uint8 fromColor, const int16 speed);
	void cycleOn(const uint8 fromColor);
	void cyclePause(const uint8 fromColor);
	void cycleAllOn();
	void cycleAllPause();
	void cycleOff(const uint8 fromColor);
	void cycleAllOff();
	void applyAllCycles();
	void applyCycles();

#pragma mark -
#pragma mark Fading
private:
	/**
	 * The fade table records the expected intensity level of each pixel
	 * in the palette that will be displayed on the next frame.
	 */
	byte _fadeTable[256];

public:
	void setFade(const uint8 percent, const uint8 fromColor, const uint16 toColor);
	void fadeOff();
	void applyFade();
};
}

#endif