gr_screen_region.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 QDENGINE_SYSTEM_GRAPHICS_GR_SCREEN_REGION_H
#define QDENGINE_SYSTEM_GRAPHICS_GR_SCREEN_REGION_H

namespace QDEngine {

#define grScreenRegion_EMPTY grScreenRegion(0, 0, 0, 0)

class grScreenRegion {
public:
    grScreenRegion() : _x(0), _y(0), _size_x(0), _size_y(0) {}
    grScreenRegion(int x, int y, int sx, int sy) : _x(x), _y(y), _size_x(sx), _size_y(sy) {}

    bool operator == (const grScreenRegion &reg) const {
        if (_x == reg._x && _y == reg._y && _size_x == reg._size_x && _size_y == reg._size_y)
            return true;

        if (is_empty() && reg.is_empty())
            return true;

        return false;
    }

    bool operator != (const grScreenRegion &reg) const {
        if (is_empty() && reg.is_empty())
            return false;

        if (_x != reg._x || _y != reg._y || _size_x != reg._size_x || _size_y != reg._size_y)
            return true;

        return false;
    }

    grScreenRegion &operator += (const grScreenRegion &reg) {
        if (reg.is_empty()) return *this;

        if (is_empty()) {
            *this = reg;
            return *this;
        }

        int x0 = (min_x() < reg.min_x()) ? min_x() : reg.min_x();
        int x1 = (max_x() > reg.max_x()) ? max_x() : reg.max_x();

        int y0 = (min_y() < reg.min_y()) ? min_y() : reg.min_y();
        int y1 = (max_y() > reg.max_y()) ? max_y() : reg.max_y();

        _x = (x0 + x1) / 2;
        _y = (y0 + y1) / 2;

        _size_x = x1 - x0;
        _size_y = y1 - y0;

        return *this;
    }

    int x() const {
        return _x;
    }
    int y() const {
        return _y;
    }

    int size_x() const {
        return _size_x;
    }
    int size_y() const {
        return _size_y;
    }

    int min_x() const {
        return _x - _size_x / 2;
    }
    int max_x() const {
        return _x + _size_x / 2;
    }

    int min_y() const {
        return _y - _size_y / 2;
    }
    int max_y() const {
        return _y + _size_y / 2;
    }

    void move(int dx, int dy) {
        _x += dx;
        _y += dy;
    }

    bool is_empty() const {
        return (!_size_x || !_size_y);
    }

    bool is_inside(int x, int y) const {
        if (x >= min_x() && x < max_x() && y >= min_y() && y < max_y()) return true;
        return false;
    }

    void clear() {
        _size_x = 0;
    }

    static const grScreenRegion EMPTY;

private:

    int _x;
    int _y;

    int _size_x;
    int _size_y;
};

} // namespace QDEngine

#endif // QDENGINE_SYSTEM_GRAPHICS_GR_SCREEN_REGION_H