CanvasImpl.java

/*
 * $Id: CanvasImpl.java 557 2008-04-17 07:13:54Z 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.Graphics;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.image.BufferedImage;
import java.awt.image.ImageObserver;

/**
 * The implementation of the Canvas interface.
 *
 * @author Wei-ju Wu
 * @version 1.0
 */
public class CanvasImpl implements Canvas {

    private BufferedImage image;
    private Graphics graphics;
    private ImageObserver observer;

    public CanvasImpl(BufferedImage image, ImageObserver observer,
            boolean antialias) {

        this.image = image;
        this.graphics = image.getGraphics();

        // activate antialiasing if set
        if (antialias) {
            ((Graphics2D) graphics).setRenderingHint(RenderingHints.KEY_ANTIALIASING,
                    RenderingHints.VALUE_ANTIALIAS_ON);
            ((Graphics2D) graphics).setRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING,
                    RenderingHints.VALUE_TEXT_ANTIALIAS_LCD_HRGB);
        } else {
            ((Graphics2D) graphics).setRenderingHint(RenderingHints.KEY_ANTIALIASING,
                    RenderingHints.VALUE_ANTIALIAS_OFF);
        }
        this.observer = observer;
    }

    public int getWidth() {

        return image.getWidth();
    }

    public int getHeight() {

        return image.getHeight();
    }

    public void setFont(Font font) {

        image.getGraphics().setFont(font);
    }

    public int getFontHeight(Font font) {

        return graphics.getFontMetrics(font).getHeight();
    }

    public int getFontAscent(Font font) {

        return graphics.getFontMetrics().getMaxAscent();
    }

    public int getCharWidth(Font font, char c) {

        return graphics.getFontMetrics(font).charWidth(c);
    }

    public int getFontDescent(Font font) {

        return graphics.getFontMetrics(font).getMaxDescent();
    }

    public int getStringWidth(Font font, String str) {

        return graphics.getFontMetrics(font).stringWidth(str);
    }

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

        graphics.setColor(color);
        graphics.fillRect(left, top, width, height);
    }

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

        graphics.setFont(font);
        graphics.setColor(color);
        graphics.drawString(str, x, y);
    }

    /**
     * {@inheritDoc}
     */
    public void scrollUp(Color backColor, Font font, int top, int height) {

        int fontHeight = getFontHeight(font);
        graphics.copyArea(0, top + fontHeight, getWidth(),
                height - fontHeight, 0, -fontHeight);
        graphics.setColor(backColor);
        graphics.fillRect(0, top + height - fontHeight,
                getWidth(), fontHeight + 1);
    }

    /**
     * {@inheritDoc}
     */
    public void scroll(Color backColor, int left, int top,
            int width, int height, int numPixels) {

        if (numPixels >= 0) {
            graphics.copyArea(left, top + numPixels, width,
                    height - numPixels, 0, -numPixels);
            graphics.setColor(backColor);
            graphics.fillRect(left, top + height - numPixels,
                    width, numPixels + 1);
        } else {

            graphics.copyArea(left, top, width, height - numPixels, 0, numPixels);
            graphics.setColor(backColor);
            graphics.fillRect(left, top, width, numPixels + 1);
        }
    }

    public void setClip(int left, int top, int width, int height) {

        graphics.setClip(left, top, width, height);
    }

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

        graphics.drawImage(image, x, y, width, height, observer);
    }

    public Color getColorAtPixel(int x, int y) {

        return new Color(image.getRGB(x, y));
    }
}