AlphaImage.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/>.
 *
 */
 
/*
 * This code is based on the CRAB engine
 *
 * Copyright (c) Arvind Raja Yadav
 *
 * Licensed under MIT
 *
 */
 
#ifndef CRAB_ALPHAIMAGE_H
#define CRAB_ALPHAIMAGE_H
 
#include "crab/image/ImageManager.h"
#include "crab/ui/element.h"
 
namespace Crab {
 
namespace pyrodactyl {
namespace ui {
class AlphaImage {
    // The image used - we don't use the image manager
    // because we don't change the alpha for those images
    ImageKey _img;
 
    // The information for drawing the image
    Element _pos;
 
    // The information related to alpha modulation of the image
    struct AlphaVal {
        int _cur, _min, _max;
 
        // Are we increasing or decreasing the alpha
        bool _inc;
 
        // By how much do we change the alpha every update
        int _change;
 
        AlphaVal() {
            _cur = 255;
            _min = 255;
            _max = 255;
            _inc = true;
            _change = 0;
        }
    } alpha;
 
public:
    AlphaImage() {
        _img = 0;
    }
 
    AlphaImage(rapidxml::xml_node<char> *node) : AlphaImage() {
        load(node);
    }
 
    ~AlphaImage() {}
 
    void load(rapidxml::xml_node<char> *node, const bool &echo = true);
 
    void draw(const int &xOffset = 0, const int &yOffset = 0);
 
    // This is used to vary the alpha
    void internalEvents();
 
    void setUI() {
        _pos.setUI();
    }
};
} // End of namespace ui
} // End of namespace pyrodactyl
 
} // End of namespace Crab
 
#endif // CRAB_ALPHAIMAGE_H