private static byte GetByteForCompression(int qtReaded, int qtRepeated)
{
byte nib1 = 0;
switch (qtReaded)
{
case 1: nib1 = 0x8; break;
case int n when(n == 2 || n == 3): nib1 = 0xC; break;
case int n when(n == 4 || n == 5): nib1 = 0xD; break;
case int n when(n == 6 || n == 7): nib1 = 0xE; break;
case int n when(n == 8 || n == 9): nib1 = 0xF; break;
}
byte nib2 = (byte)(qtRepeated - 2);
if (qtReaded % 2 == 1 && nib1 != 0x8)
{
nib2 += 8;
}
return(CGeneric.NibbleToByte(nib1, nib2));
}
private static (byte[] palette, byte[] data) ConvertRGBAtoMax16Colors(byte[] texture)
{
//construct palette and use it.
List <Color> colors = ExtractPaletteFromByteArray(texture);
//first array for palette color
byte[] palette = new byte[colors.Count * 4];
//second array for palette data
byte[] finalArray = new byte[texture.Length / 8];
// write palette
for (int i = 0; i < colors.Count(); i++)
{
palette[i * 4] = colors[i].R;
palette[i * 4 + 1] = colors[i].G;
palette[i * 4 + 2] = colors[i].B;
palette[i * 4 + 3] = colors[i].A;
}
int index = 0;
byte nibble1;
byte nibble2;
// write data with palette information
for (int i = 0; i < texture.Length; i += 8)
{
nibble1 = GetIndexFromPalette(colors, Color.FromArgb(texture[i + 3], texture[i], texture[i + 1], texture[i + 2]));
nibble2 = GetIndexFromPalette(colors, Color.FromArgb(texture[i + 7], texture[i + 4], texture[i + 5], texture[i + 6]));
finalArray[index] = CGeneric.NibbleToByte(nibble1, nibble2);
index++;
}
return(palette, finalArray);
}
//specific format for BFF header
private static byte[] SetHeader(CGeneric.Compression textureType, byte greenAlphaIndex, byte compressedValue, byte[] displayedWidth, byte[] pixelWidth, byte[] displayHeight, byte[] bffName, byte[] colorCount)
{
//fixedsize = 36 + bffName + 1 if bffName size is not pair + 4 for palette color count
byte[] headerBFF2 = new Byte[36 + bffName.Length + bffName.Length % 2 + colorCount.Length];
headerBFF2[8] = 0x8;
//write "BFF2"
for (int i = 0; i < CGeneric.patternBFF2.Length; i++)
{
headerBFF2[12 + i] = CGeneric.patternBFF2[i];
}
//decompose the next two bytes in nibbles
//grab the nibbles of alpha color
List <byte> alphaColor = CGeneric.ByteToNibble(greenAlphaIndex);
//write two nibbles for the both bytes..
headerBFF2[17] = CGeneric.NibbleToByte(2, alphaColor[0]);
headerBFF2[18] = CGeneric.NibbleToByte(alphaColor[1], compressedValue);
//write texture type
headerBFF2[19] = (byte)textureType;
//write displayed width
for (int i = 0; i < displayedWidth.Length; i++)
{
headerBFF2[20 + i] = displayedWidth[i];
}
//write pixel width
for (int i = 0; i < pixelWidth.Length; i++)
{
headerBFF2[22 + i] = pixelWidth[i];
}
//write display height
for (int i = 0; i < displayHeight.Length; i++)
{
headerBFF2[26 + i] = displayHeight[i];
}
//prepare instruction length (depending of the pixelWidth value)
double instructionLengthValue = CGeneric.ConvertByteArrayToInt(pixelWidth);
switch (textureType)
{
case CGeneric.Compression.greyscale: instructionLengthValue *= 2; break;
case CGeneric.Compression.max16Colors: instructionLengthValue /= 2; break;
case CGeneric.Compression.trueColor16Bits: instructionLengthValue *= 2; break;
case CGeneric.Compression.trueColor32Bits: instructionLengthValue *= 4; break;
}
byte[] instructLength = CGeneric.ConvertIntToByteArray((int)Math.Floor(instructionLengthValue));
//write instruction length
for (int i = 0; i < instructLength.Length; i++)
{
headerBFF2[28 + i] = instructLength[i];
}
//length of file name
if (bffName.Length % 2 == 0)
{
headerBFF2[35] = (byte)bffName.Length;
}
else
{
headerBFF2[35] = (byte)(bffName.Length + 1);
}
//write bff name
for (int i = 0; i < bffName.Length; i++)
{
headerBFF2[36 + i] = bffName[i];
}
for (int i = 0; i < colorCount.Length; i++)
{
headerBFF2[36 + bffName.Length + bffName.Length % 2 + i] = colorCount[i];
}
return(headerBFF2);
}
