hardwarecursor.java

来自「纯java操作系统jnode,安装简单和操作简单的个人使用的Java操作系统」· Java 代码 · 共 101 行

/*
 * $Id: HardwareCursor.java,v 1.1 2003/12/21 08:46:47 epr Exp $
 */
package org.jnode.driver.video;

import java.util.HashMap;
import java.util.Iterator;

/**
 * @author Ewout Prangsma ([e-mail])
 */
public class HardwareCursor {

	/** The images */
	private final HashMap imageMap;

	/**
	 * Initialize this instance.
	 * 
	 * @param images
	 */
	public HardwareCursor(HardwareCursorImage[] images) {
		this.imageMap = new HashMap();
		for (int i = 0; i < images.length; i++) {
			final HardwareCursorImage img = images[i];
			imageMap.put(getKey(img.getWidth(), img.getHeight()), img);
		}
	}

	/**
	 * Gets the best cursor image for the given size.
	 * 
	 * @param width
	 * @param height
	 * @return HardwareCursorImage
	 */
	public HardwareCursorImage getImage(int width, int height) {
		final String key = getKey(width, height);
		HardwareCursorImage img = (HardwareCursorImage) imageMap.get(key);
		if (img == null) {
			if (width > 16) {
				img = scaleImage(getImage(width / 2, height / 2));
				if (img != null) {
					imageMap.put(key, img);
				}
			}
		}
		return img;
	}

	/**
	 * Create an iterator over all images.
	 * 
	 * @return An iterator of {@link HardwareCursor}instances.
	 */
	public Iterator iterator() {
		return imageMap.values().iterator();
	}

	/**
	 * Create a key for use in imageMap.
	 * 
	 * @param width
	 * @param height
	 * @return
	 */
	private String getKey(int width, int height) {
		return "" + width + "-" + height;
	}

	/**
	 * Scale the given image by a factor of 2.
	 * 
	 * @param src
	 * @return HardwareCursorImage
	 */
	private HardwareCursorImage scaleImage(HardwareCursorImage src) {
		final int w = src.getWidth();
		final int h = src.getHeight();
		final int nw = w * 2;
		final int nh = h * 2;

		final int[] argb = src.getImage();
		final int[] nargb = new int[nw * nh];

		for (int y = 0; y < h; y++) {
			final int ny = y * 2;
			for (int x = 0; x < w; x++) {
				final int nx = x * 2;
				final int v = argb[y * w + x];
				nargb[ny * nw + nx] = v;
				nargb[(ny + 1) * nw + nx] = v;
				nargb[ny * nw + nx + 1] = v;
				nargb[(ny + 1) * nw + nx + 1] = v;
			}
		}

		return new HardwareCursorImage(nw, nh, nargb, src.getHotSpotX() * 2, src.getHotSpotY() * 2);
	}
}