public static DX10_Helpers.LDRColour[] DecompressBC7(byte[] source, int sourceStart)
{
int start = 0;
while (start < 128 && DX10_Helpers.GetBit(source, sourceStart, ref start) == 0)
{
}
int modeVal = start - 1;
Mode mode = Modes[modeVal];
var outColours = new DX10_Helpers.LDRColour[DX10_Helpers.NUM_PIXELS_PER_BLOCK];
if (modeVal < 8)
{
int partitions = mode.Partitions;
int numEndPoints = (partitions + 1) << 1;
int indexPrecision = mode.IndexPrecision;
int APrecision = mode.APrecision;
int i;
int[] P = new int[mode.PBits];
int shape = DX10_Helpers.GetBits(source, sourceStart, ref start, mode.PartitionBits);
int rotation = DX10_Helpers.GetBits(source, sourceStart, ref start, mode.RotationBits);
int indexMode = DX10_Helpers.GetBits(source, sourceStart, ref start, mode.IndexModeBits);
DX10_Helpers.LDRColour[] c = new DX10_Helpers.LDRColour[6];
DX10_Helpers.LDRColour RGBPrecision = mode.RawRGBPrecision;
DX10_Helpers.LDRColour RGBPrecisionWithP = mode.RGBPrecisionWithP;
// Red
for (i = 0; i < numEndPoints; i++)
{
if (start + RGBPrecision.R > 128)
{
Debugger.Break(); // Error
}
c[i].R = DX10_Helpers.GetBits(source, sourceStart, ref start, RGBPrecision.R);
}
// Green
for (i = 0; i < numEndPoints; i++)
{
if (start + RGBPrecision.G > 128)
{
Debugger.Break(); // Error
}
c[i].G = DX10_Helpers.GetBits(source, sourceStart, ref start, RGBPrecision.G);
}
// Blue
for (i = 0; i < numEndPoints; i++)
{
if (start + RGBPrecision.B > 128)
{
Debugger.Break(); // Error
}
c[i].B = DX10_Helpers.GetBits(source, sourceStart, ref start, RGBPrecision.B);
}
// Alpha
for (i = 0; i < numEndPoints; i++)
{
if (start + RGBPrecision.A > 128)
{
Debugger.Break(); // Error
}
c[i].A = RGBPrecision.A == 0 ? 255 : DX10_Helpers.GetBits(source, sourceStart, ref start, RGBPrecision.A);
}
// P Bits
for (i = 0; i < mode.PBits; i++)
{
if (start > 127)
{
Debugger.Break();
// Error
}
P[i] = DX10_Helpers.GetBit(source, sourceStart, ref start);
}
// Adjust for P bits
bool rDiff = RGBPrecision.R != RGBPrecisionWithP.R;
bool gDiff = RGBPrecision.G != RGBPrecisionWithP.B;
bool bDiff = RGBPrecision.G != RGBPrecisionWithP.G;
bool aDiff = RGBPrecision.A != RGBPrecisionWithP.A;
if (mode.PBits != 0)
{
for (i = 0; i < numEndPoints; i++)
{
int pi = i * mode.PBits / numEndPoints;
if (rDiff)
{
c[i].R = (c[i].R << 1) | P[pi];
}
if (gDiff)
{
c[i].G = (c[i].G << 1) | P[pi];
}
if (bDiff)
{
c[i].B = (c[i].B << 1) | P[pi];
}
if (aDiff)
{
c[i].A = (c[i].A << 1) | P[pi];
}
}
}
for (i = 0; i < numEndPoints; i++)
{
c[i] = DX10_Helpers.Unquantise(c[i], RGBPrecisionWithP);
}
int[] w1 = new int[DX10_Helpers.NUM_PIXELS_PER_BLOCK];
int[] w2 = new int[DX10_Helpers.NUM_PIXELS_PER_BLOCK];
// Read colour indicies
for (i = 0; i < DX10_Helpers.NUM_PIXELS_PER_BLOCK; i++)
{
int numBits = DX10_Helpers.IsFixUpOffset(partitions, shape, i) ? indexPrecision - 1 : indexPrecision;
if (start + numBits > 128)
{
Debugger.Break();
// Error
}
w1[i] = DX10_Helpers.GetBits(source, sourceStart, ref start, numBits);
}
// Read Alpha
if (APrecision != 0)
{
for (i = 0; i < DX10_Helpers.NUM_PIXELS_PER_BLOCK; i++)
{
int numBits = i != 0 ? APrecision : APrecision - 1;
if (start + numBits > 128)
{
Debugger.Break();
// Error
}
w2[i] = DX10_Helpers.GetBits(source, sourceStart, ref start, numBits);
}
}
for (i = 0; i < DX10_Helpers.NUM_PIXELS_PER_BLOCK; i++)
{
int region = DX10_Helpers.PartitionTable[partitions][shape][i];
DX10_Helpers.LDRColour outPixel;
if (APrecision == 0)
{
outPixel = Interpolate(c[region << 1], c[(region << 1) + 1], w1[i], w1[i], indexPrecision, indexPrecision);
}
else
{
if (indexMode == 0)
{
outPixel = Interpolate(c[region << 1], c[(region << 1) + 1], w1[i], w2[i], indexPrecision, APrecision);
}
else
{
outPixel = Interpolate(c[region << 1], c[(region << 1) + 1], w2[i], w1[i], APrecision, indexPrecision);
}
}
switch (rotation)
{
case 1:
int temp = outPixel.R;
outPixel.R = outPixel.A;
outPixel.A = temp;
break;
case 2:
temp = outPixel.G;
outPixel.G = outPixel.A;
outPixel.A = temp;
break;
case 3:
temp = outPixel.B;
outPixel.B = outPixel.A;
outPixel.A = temp;
break;
}
outColours[i] = outPixel;
}
return(outColours);
}
return(outColours);
}
private static DX10_Helpers.LDRColour Interpolate(DX10_Helpers.LDRColour lDRColour1, DX10_Helpers.LDRColour lDRColour2, int wc, int wa, int wcPrec, int waPrec)
{
DX10_Helpers.LDRColour temp = DX10_Helpers.InterpolateRGB(lDRColour1, lDRColour2, wc, wcPrec);
temp.A = DX10_Helpers.InterpolateA(lDRColour1, lDRColour2, wa, waPrec);
return(temp);
}