private BufferedImage decodeDxt3Buffer() {
int numBlocksWide = width / BLOCK_SIZE;
int numBlocksHigh = height / BLOCK_SIZE;
// always at least 1x1 tile
numBlocksWide = numBlocksWide < 1 ? 1 : numBlocksWide;
numBlocksHigh = numBlocksHigh < 1 ? 1 : numBlocksHigh;
int blockWidth = Math.min(width, BLOCK_SIZE);
int blockHeight = Math.min(height, BLOCK_SIZE);
int[] pixels = new int[blockWidth * blockHeight];
BufferedImage delegate = new BufferedImage(width, height, BufferedImage.TYPE_INT_ARGB);
// One copy of table to minimises new calls
Color24[] table = new Color24[4];
table[0] = new Color24();
table[1] = new Color24();
table[2] = new Color24();
table[3] = new Color24();
for (int row = 0; row < numBlocksHigh; row++) {
for (int col = 0; col < numBlocksWide; col++) {
long alphaData = buffer.getLong();
short minColor = buffer.getShort();
short maxColor = buffer.getShort();
int colorIndexMask = buffer.getInt();
Color24[] lookupTable = Color24.expandLookupTable(table, minColor, maxColor);
for (int br = 0; br < blockHeight; br++) {
for (int bc = 0; bc < blockWidth; bc++) {
int k = (br * blockWidth) + bc;
int alpha = (int) (alphaData >>> (k * 4)) & 0xF; // Alphas are just 4 bits per pixel
alpha <<= 4;
int colorIndex = (colorIndexMask >>> k * 2) & 0x03;
Color24 color = lookupTable[colorIndex];
int pixel8888 = (alpha << 24) | color.pix888;
// for yUp must flip it , so NOT pixels[br * blockWidth + bc] = pixel8888;
pixels[((blockHeight - 1) - br) * blockWidth + bc] = pixel8888;
}
}
// notice vertical flipping there
delegate.setRGB(
col * blockWidth,
(height - blockHeight) - (row * blockHeight),
blockWidth,
blockHeight,
pixels,
0,
blockWidth);
}
}
return delegate;
}
private BufferedImage decompressRGBA_S3TC_DXT5_EXT() {
int numBlocksWide = width / BLOCK_SIZE;
int numBlocksHigh = height / BLOCK_SIZE;
// always at least 1x1 tile
numBlocksWide = numBlocksWide < 1 ? 1 : numBlocksWide;
numBlocksHigh = numBlocksHigh < 1 ? 1 : numBlocksHigh;
int blockWidth = Math.min(width, BLOCK_SIZE);
int blockHeight = Math.min(height, BLOCK_SIZE);
int[] pixels = new int[blockWidth * blockHeight];
BufferedImage delegate = new BufferedImage(width, height, BufferedImage.TYPE_INT_ARGB);
// One copy of table to minimises new calls
Color24[] table = new Color24[4];
table[0] = new Color24();
table[1] = new Color24();
table[2] = new Color24();
table[3] = new Color24();
for (int row = 0; row < numBlocksHigh; row++) {
for (int col = 0; col < numBlocksWide; col++) {
int alpha0 = buffer.get() & 0xff; // unsigned byte
int alpha1 = buffer.get() & 0xff; // unsigned byte
// next 6 bytes are a look up list (note long casts, important!)
long alphaBits =
(buffer.get() & 0xffL) << 0L //
| (buffer.get() & 0xffL) << 8L //
| (buffer.get() & 0xffL) << 16L //
| (buffer.get() & 0xffL) << 24L //
| (buffer.get() & 0xffL) << 32L //
| (buffer.get() & 0xffL) << 40L; //
short minColor = buffer.getShort();
short maxColor = buffer.getShort();
int colorIndexMask = buffer.getInt();
Color24[] lookupTable = Color24.expandLookupTable(table, minColor, maxColor);
for (int br = 0; br < blockHeight; br++) {
for (int bc = 0; bc < blockWidth; bc++) {
int k = (br * blockWidth) + bc;
int alphaCode = (int) (alphaBits >> (3 * k) & 0x07); // bottom 3 bits
int alpha = 0;
if (alphaCode == 0) {
alpha = alpha0;
} else if (alphaCode == 1) {
alpha = alpha1;
} else if (alpha0 > alpha1) {
alpha = ((8 - alphaCode) * alpha0 + (alphaCode - 1) * alpha1) / 7;
} else {
if (alphaCode == 6) alpha = 0;
else if (alphaCode == 7) alpha = 255;
else alpha = ((6 - alphaCode) * alpha0 + (alphaCode - 1) * alpha1) / 5;
}
int colorIndex = (colorIndexMask >>> k * 2) & 0x03;
Color24 color = lookupTable[colorIndex];
int pixel8888 = (alpha << 24) | color.pix888;
// for yUp must flip it , so NOT pixels[br * blockWidth + bc] = pixel8888;
pixels[((blockHeight - 1) - br) * blockWidth + bc] = pixel8888;
}
}
// notice vertical flipping there
delegate.setRGB(
col * blockWidth,
(height - blockHeight) - (row * blockHeight),
blockWidth,
blockHeight,
pixels,
0,
blockWidth);
}
}
return delegate;
}
private BufferedImage decodeDxt1Buffer() {
int numBlocksWide = width / BLOCK_SIZE;
int numBlocksHigh = height / BLOCK_SIZE;
// always at least 1x1 tile
numBlocksWide = numBlocksWide < 1 ? 1 : numBlocksWide;
numBlocksHigh = numBlocksHigh < 1 ? 1 : numBlocksHigh;
int blockWidth = Math.min(width, BLOCK_SIZE);
int blockHeight = Math.min(height, BLOCK_SIZE);
int[] pixels = new int[blockWidth * blockHeight];
BufferedImage delegate = new BufferedImage(width, height, BufferedImage.TYPE_INT_ARGB);
// One copy of table to minimises new calls
Color24[] table = new Color24[4];
table[0] = new Color24();
table[1] = new Color24();
table[2] = new Color24();
table[3] = new Color24();
for (int row = 0; row < numBlocksHigh; row++) {
for (int col = 0; col < numBlocksWide; col++) {
short c0 = buffer.getShort();
short c1 = buffer.getShort();
int colorIndexMask = buffer.getInt();
// http://en.wikipedia.org/wiki/S3_Texture_Compression
if (ignoreAlpha || !Color24.hasAlphaBit(c0, c1)) {
Color24[] lookupTable = Color24.expandLookupTable(table, c0, c1);
for (int br = 0; br < blockHeight; br++) {
for (int bc = 0; bc < blockWidth; bc++) {
int k = (br * blockWidth) + bc;
int colorIndex = (colorIndexMask >>> k * 2) & 0x03;
// for yUp must flip it so NOT pixels[br * blockWidth + bc] = (0xFF << 24) |
// lookupTable[colorIndex].pix888;
pixels[((blockHeight - 1) - br) * blockWidth + bc] =
(0xFF << 24) | lookupTable[colorIndex].pix888;
}
}
} else {
Color24[] lookupTable = Color24.expandLookupTableAlphable(table, c0, c1);
for (int br = 0; br < blockHeight; br++) {
for (int bc = 0; bc < blockWidth; bc++) {
int k = (br * blockWidth) + bc;
int colorIndex = (colorIndexMask >>> k * 2) & 0x03;
int alpha = (colorIndex == 3) ? 0x00 : 0xFF;
// for yUp must flip it , so NOT pixels[br * blockWidth + bc] = (alpha << 24) |
// lookupTable[colorIndex].pix888;
pixels[((blockHeight - 1) - br) * blockWidth + bc] =
(alpha << 24) | lookupTable[colorIndex].pix888;
}
}
}
delegate.setRGB(
col * blockWidth,
(height - blockHeight) - (row * blockHeight),
blockWidth,
blockHeight,
pixels,
0,
blockWidth);
}
}
return delegate;
}
