sneedmc/depends/launcher/org/multimc/IconLoader.java
2015-08-14 23:30:12 +02:00

132 lines
4.6 KiB
Java

package org.multimc;
import javax.imageio.ImageIO;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.nio.ByteBuffer;
/*****************************************************************************
* A convenience class for loading icons from images.
*
* Icons loaded from this class are formatted to fit within the required
* dimension (16x16, 32x32, or 128x128). If the source image is larger than the
* target dimension, it is shrunk down to the minimum size that will fit. If it
* is smaller, then it is only scaled up if the new scale can be a per-pixel
* linear scale (i.e., x2, x3, x4, etc). In both cases, the image's width/height
* ratio is kept the same as the source image.
*
* @author Chris Molini
*****************************************************************************/
public class IconLoader
{
/*************************************************************************
* Loads an icon in ByteBuffer form.
*
* @param filepath
* The location of the Image to use as an icon.
*
* @return An array of ByteBuffers containing the pixel data for the icon in
* various sizes (as recommended by the OS).
*************************************************************************/
public static ByteBuffer[] load(String filepath)
{
BufferedImage image;
try {
image = ImageIO.read ( new File( filepath ) );
} catch ( IOException e ) {
e.printStackTrace();
return new ByteBuffer[0];
}
ByteBuffer[] buffers;
buffers = new ByteBuffer[1];
buffers[0] = loadInstance(image, 128);
return buffers;
}
/*************************************************************************
* Copies the supplied image into a square icon at the indicated size.
*
* @param image
* The image to place onto the icon.
* @param dimension
* The desired size of the icon.
*
* @return A ByteBuffer of pixel data at the indicated size.
*************************************************************************/
private static ByteBuffer loadInstance(BufferedImage image, int dimension)
{
BufferedImage scaledIcon = new BufferedImage(dimension, dimension,
BufferedImage.TYPE_INT_ARGB_PRE);
Graphics2D g = scaledIcon.createGraphics();
double ratio = getIconRatio(image, scaledIcon);
double width = image.getWidth() * ratio;
double height = image.getHeight() * ratio;
g.drawImage(image, (int) ((scaledIcon.getWidth() - width) / 2),
(int) ((scaledIcon.getHeight() - height) / 2), (int) (width),
(int) (height), null);
g.dispose();
return convertToByteBuffer(scaledIcon);
}
/*************************************************************************
* Gets the width/height ratio of the icon. This is meant to simplify
* scaling the icon to a new dimension.
*
* @param src
* The base image that will be placed onto the icon.
* @param icon
* The icon that will have the image placed on it.
*
* @return The amount to scale the source image to fit it onto the icon
* appropriately.
*************************************************************************/
private static double getIconRatio(BufferedImage src, BufferedImage icon)
{
double ratio = 1;
if (src.getWidth() > icon.getWidth())
ratio = (double) (icon.getWidth()) / src.getWidth();
else
ratio = (int) (icon.getWidth() / src.getWidth());
if (src.getHeight() > icon.getHeight())
{
double r2 = (double) (icon.getHeight()) / src.getHeight();
if (r2 < ratio)
ratio = r2;
}
else
{
double r2 = (int) (icon.getHeight() / src.getHeight());
if (r2 < ratio)
ratio = r2;
}
return ratio;
}
/*************************************************************************
* Converts a BufferedImage into a ByteBuffer of pixel data.
*
* @param image
* The image to convert.
*
* @return A ByteBuffer that contains the pixel data of the supplied image.
*************************************************************************/
public static ByteBuffer convertToByteBuffer(BufferedImage image)
{
byte[] buffer = new byte[image.getWidth() * image.getHeight() * 4];
int counter = 0;
for (int i = 0; i < image.getHeight(); i++)
for (int j = 0; j < image.getWidth(); j++)
{
int colorSpace = image.getRGB(j, i);
buffer[counter + 0] = (byte) ((colorSpace << 8) >> 24);
buffer[counter + 1] = (byte) ((colorSpace << 16) >> 24);
buffer[counter + 2] = (byte) ((colorSpace << 24) >> 24);
buffer[counter + 3] = (byte) (colorSpace >> 24);
counter += 4;
}
return ByteBuffer.wrap(buffer);
}
}