Canvas.java

/*
 * $Id: Canvas.java 535 2008-02-19 06:02:50Z weiju $
 * 
 * Created on 2006/01/23
 * Copyright 2005-2008 by Wei-ju Wu
 * This file is part of The Z-machine Preservation Project (ZMPP).
 *
 * ZMPP 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.
 *
 * ZMPP 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 ZMPP.  If not, see <http://www.gnu.org/licenses/>.
 */
package org.zmpp.swingui;

import java.awt.Color;
import java.awt.Font;
import java.awt.image.BufferedImage;

/**
 * This interface defines an abstract access to the Java graphics system so it
 * will be easier to test.
 *
 * @author Wei-ju Wu
 * @version 1.0
 */
public interface Canvas {

    int getWidth();

    int getHeight();

    int getFontHeight(Font font);

    int getFontAscent(Font font);

    int getFontDescent(Font font);

    int getCharWidth(Font font, char c);

    int getStringWidth(Font font, String str);

    /**
     * Scroll up one line. For regular games.
     *
     * @param backColor the background color
     * @param font the font
     * @param top the top coordinate
     * @param height the area height
     */
    void scrollUp(Color backColor, Font font, int top, int height);

    /**
     * Scrolling for V6 games.
     *
     * @param backColor the background color
     * @param left the left coordinate of the area
     * @param top the top coordinate of the area
     * @param width the area width
     * @param height the height
     * @param numPixels the number of pixels
     */
    void scroll(Color backColor, int left, int top, int width,
            int height, int numPixels);

    void fillRect(Color color, int left, int top, int width, int height);

    void drawString(Color color, Font font, int x, int y, String str);

    void setClip(int left, int top, int width, int height);

    void drawImage(BufferedImage image, int x, int y, int width, int height);

    Color getColorAtPixel(int x, int y);
}