|
public static UnpackColor ( PixelFormat pf, |
||
| pf | PixelFormat | Pixelformat in which to read the color |
| src | Source memory location | |
| return | ||
private void Unpack(ref ColorEx dst, int x, int y, int z, PixelFormat format, BufferBase src, PixelBox srcbox,
int elemsize)
{
var data = src + (elemsize * ((x) + (y) * srcbox.RowPitch + (z) * srcbox.SlicePitch));
dst = PixelConverter.UnpackColor(format, data);
}
private void _unpackDXTColor(PixelFormat pf, DXTColorBlock block, ColorEx[] pCol)
{
// Note - we assume all values have already been endian swapped
// Colour lookup table
var derivedColours = new ColorEx[4];
using (var src = BufferBase.Wrap(block.colour_0, 1))
{
derivedColours[0] = PixelConverter.UnpackColor(PixelFormat.R5G6B5, src);
}
using (var src = BufferBase.Wrap(block.colour_1, 1))
{
derivedColours[1] = PixelConverter.UnpackColor(PixelFormat.R5G6B5, src);
}
if (pf == PixelFormat.DXT1 && block.colour_0 <= block.colour_1)
{
// 1-bit alpha
// one intermediate colour, half way between the other two
derivedColours[2] = (derivedColours[0] + derivedColours[1]) / 2;
// transparent colour
derivedColours[3] = new ColorEx(0, 0, 0, 0);
}
else
{
// first interpolated colour, 1/3 of the way along
derivedColours[2] = (derivedColours[0] * 2 + derivedColours[1]) / 3;
// second interpolated colour, 2/3 of the way along
derivedColours[3] = (derivedColours[0] + derivedColours[1] * 2) / 3;
}
// Process 4x4 block of texels
for (var row = 0; row < 4; ++row)
{
for (var x = 0; x < 4; ++x)
{
// LSB come first
var colIdx = (byte)block.indexRow[row] >> (x * 2) & 0x3;
if (pf == PixelFormat.DXT1)
{
// Overwrite entire colour
pCol[(row * 4) + x] = derivedColours[colIdx];
}
else
{
// alpha has already been read (alpha precedes colour)
var col = pCol[(row * 4) + x];
col.r = derivedColours[colIdx].r;
col.g = derivedColours[colIdx].g;
col.b = derivedColours[colIdx].b;
}
}
}
}
