Java Draw Image drawVolatileImage(Graphics2D g, VolatileImage volatileImage, int x, int y, Image orig)

Description

From The Java Developers Almanac 1.4
e674.

License

Minecraft Mod Public

Parameter

Parameter	Description
g	The destination for drawing.
volatileImage	The image that will be drawn. Might be null, in which case a new volatile image is created.
x	Horizontal position for drawing the image.
y	Vertical position for drawing the image.
orig	The original image that will be converted to a VolatileImage, if volatileImage is null, or if volatileImage is not valid anymore.

Return

Returns a VolatileImage if one has been created, null otherwise. Pass this VolatileImage to subsequent calls of drawVolatileImage.

Declaration

public static VolatileImage drawVolatileImage(Graphics2D g, VolatileImage volatileImage, int x, int y,
        Image orig) 

Method Source Code

//package com.java2s;
import java.awt.*;

import java.awt.image.*;

public class Main {
    /**//from   w  w  w  . ja va2s  .c o m
     * From The Java Developers Almanac 1.4 <br>
     * e674. Creating and Drawing an Accelerated Image
     * This method draws a volatile image and returns it, or possibly a
     * newly created volatile image object. Subsequent calls to this method
     * should always use the returned volatile image.
     * If the contents of the image is lost, it is recreated using orig.
     * img may be null, in which case a new volatile image is created.
     * @param g The destination for drawing.
     * @param volatileImage The image that will be drawn. Might be null, in
     * which case a new volatile image is created.
     * @param x Horizontal position for drawing the image.
     * @param y Vertical position for drawing the image.
     * @return Returns a VolatileImage if one has been created, null otherwise.
     * Pass this VolatileImage to subsequent calls of drawVolatileImage.
     * @param orig The original image that will be converted to a VolatileImage,
     * if volatileImage is null, or if volatileImage is not valid anymore.
     */
    public static VolatileImage drawVolatileImage(Graphics2D g, VolatileImage volatileImage, int x, int y,
            Image orig) {

        final boolean VERBOSE = false;

        final int MAX_TRIES = 5;
        for (int i = 0; i < MAX_TRIES; i++) {

            if (VERBOSE) {
                System.out.println("try " + (i + 1));
            }
            if (volatileImage == null) {
                // Create the volatile image
                final int imageWidth = orig.getWidth(null);
                final int imageHeight = orig.getHeight(null);
                volatileImage = g.getDeviceConfiguration().createCompatibleVolatileImage(imageWidth, imageHeight);
                // Copy the original image to accelerated image memory
                Graphics2D gc = (Graphics2D) volatileImage.createGraphics();
                gc.drawImage(orig, 0, 0, null);
                gc.dispose();
                if (VERBOSE) {
                    System.out.println("volatile image was not created before, created new volatile image of size: "
                            + imageWidth + " x " + imageHeight);
                }
            }

            if (volatileImage != null) {
                // Draw the volatile image
                g.drawImage(volatileImage, x, y, null);

                // Check if it is still valid
                if (!volatileImage.contentsLost()) {
                    if (VERBOSE) {
                        System.out.println(
                                "drawn volatile image, volatile image still valid, exiting drawVolatileImage");
                    }
                    return volatileImage;
                }

                if (VERBOSE) {
                    System.out.println("drawn volatile image, image not valid");
                }
            }

            // Determine how to fix the volatile image
            switch (volatileImage.validate(g.getDeviceConfiguration())) {
            case VolatileImage.IMAGE_OK:
                // This should not happen
                if (VERBOSE) {
                    System.out.println("VolatileImage.validate returned IMAGE_OK");
                }
                break;
            case VolatileImage.IMAGE_INCOMPATIBLE:
                // Create a new volatile image object;
                // this could happen if the component was moved to another device
                volatileImage.flush();
                volatileImage = g.getDeviceConfiguration().createCompatibleVolatileImage(orig.getWidth(null),
                        orig.getHeight(null));
                if (VERBOSE) {
                    System.out.println("VolatileImage.validate returned IMAGE_INCOMPATIBLE");
                }
            case VolatileImage.IMAGE_RESTORED:
                // Copy the original image to accelerated image memory
                Graphics2D gc = (Graphics2D) volatileImage.createGraphics();
                gc.drawImage(orig, 0, 0, null);
                gc.dispose();
                if (VERBOSE) {
                    System.out.println("VolatileImage.validate returned IMAGE_RESTORED");
                }
                break;
            }
        }

        // The image failed to be drawn after MAX_TRIES;
        // draw with the non-accelerated image
        if (VERBOSE) {
            System.out.println("Could not draw volatile image. Will draw normal image.");
        }
        g.drawImage(orig, x, y, null);
        return volatileImage;
    }
}

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3. drawTransparentImageInOval(Graphics2D gr, Image img, Rectangle r, boolean noShrink, double transparency)
4. drawVerticalBar(final BufferedImage image, final double max, final double min)
5. drawVerticalLineAt(int x, int dottedLine, Color color, BufferedImage displayMap)