larryScale.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 3 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, see <http://www.gnu.org/licenses/>.
 *
 */

#ifndef GRAPHICS_LARRYSCALE_H
#define GRAPHICS_LARRYSCALE_H

#include "common/scummsys.h"

namespace Graphics {

/*

LarryScale is a bitmap scaler for cartoon images.

Features:

* Supports arbitrary scaling factors along both axes (but looks best between 50% and 200%).
* When downscaling: preserves fine details.
* When upscaling: keeps lines smooth, introducing very few block artifacts.
* Does not introduce additional colors.

Limitations:

* Lines must not be anti-aliased and should be only one pixel wide.
* Fills should be flat without gradients.

*/

typedef byte LarryScaleColor;

class RowReader {
public:
    virtual const LarryScaleColor *readRow(int y) = 0;
    virtual ~RowReader() {}
};

class RowWriter {
public:
    virtual void writeRow(int y, const LarryScaleColor *row) = 0;
    virtual ~RowWriter() {}
};

void larryScale(
    int srcWidth, int srcHeight,
    LarryScaleColor transparentColor,
    RowReader &rowReader,
    int dstWidth, int dstHeight,
    RowWriter &rowWriter
);

}

#endif