public void compressImage(java.awt.image.BufferedImage image, DXTCompressionAttributes attributes,
java.nio.ByteBuffer buffer)
{
if (image == null)
{
String message = Logging.getMessage("nullValue.ImageIsNull");
Logging.logger().severe(message);
throw new ArgumentException(message);
}
if (attributes == null)
{
String message = Logging.getMessage("nullValue.AttributesIsNull");
Logging.logger().severe(message);
throw new ArgumentException(message);
}
if (buffer == null)
{
String message = Logging.getMessage("nullValue.BufferNull");
Logging.logger().severe(message);
throw new ArgumentException(message);
}
ColorBlock4x4 colorBlock = new ColorBlock4x4();
ColorBlockExtractor colorBlockExtractor = this.getColorBlockExtractor(image);
BlockDXT3 dxt3Block = new BlockDXT3();
BlockDXT3Compressor dxt3Compressor = new BlockDXT3Compressor();
int width = image.getWidth();
int height = image.getHeight();
for (int j = 0; j < height; j += 4)
{
for (int i = 0; i < width; i += 4)
{
colorBlockExtractor.extractColorBlock4x4(attributes, i, j, colorBlock);
dxt3Compressor.compressBlockDXT3(colorBlock, attributes, dxt3Block);
AlphaBlockDXT3 dxtAlphaBlock = dxt3Block.getAlphaBlock();
buffer.putLong(dxtAlphaBlock.alphaValueMask);
BlockDXT1 dxtColorBlock = dxt3Block.getColorBlock();
buffer.putShort((short)dxtColorBlock.color0);
buffer.putShort((short)dxtColorBlock.color1);
buffer.putInt((int)dxtColorBlock.colorIndexMask);
}
}
}
/**
* Compress the 4x4 color block into a DXT2/DXT3 block using 16 4 bit alpha values, and four colors. This method
* compresses the color block exactly as a DXT1 compressor, except that it guarantees that the DXT1 block will use
* four colors.
* <p/>
* Access to this method must be synchronized by the caller. This method is frequently invoked by the DXT
* compressor, so in order to reduce garbage each instance of this class has unsynchronized properties that are
* reused during each call.
*
* @param colorBlock the 4x4 color block to compress.
* @param attributes attributes that will control the compression.
* @param dxtBlock the DXT2/DXT3 block that will receive the compressed data.
* @throws ArgumentException if either <code>colorBlock</code> or <code>dxtBlock</code> are null.
*/
public void compressBlockDXT3(ColorBlock4x4 colorBlock, DXTCompressionAttributes attributes, BlockDXT3 dxtBlock)
{
if (colorBlock == null)
{
String message = Logging.getMessage("nullValue.ColorBlockIsNull");
Logging.logger().severe(message);
throw new ArgumentException(message);
}
if (attributes == null)
{
String message = Logging.getMessage("nullValue.AttributesIsNull");
Logging.logger().severe(message);
throw new ArgumentException(message);
}
if (dxtBlock == null)
{
String message = Logging.getMessage("nullValue.DXTBlockIsNull");
Logging.logger().severe(message);
throw new ArgumentException(message);
}
// The DXT3 color block is compressed exactly like the DXT1 color block, except that the four color palette is
// always used, no matter the ordering of color0 and color1. At this stage we only consider color values,
// not alpha.
this.dxt1Compressor.compressBlockDXT1(colorBlock, attributes, dxtBlock.colorBlock);
// The DXT3 alpha block can be compressed separately.
this.compressBlockDXT3a(colorBlock, dxtBlock.alphaBlock);
}
