static void Process8BitIndexedRow(ImageLine imageLine, Chunks.PngChunkPLTE plte, Chunks.PngChunkTRNS trns, Color[] pixels)
{
#if DEBUG
UnityEngine.Assertions.Assert.IsNotNull(trns, "make sure this image contains no transparency data");
#endif
int row = imageLine.ImageRow;
ImageInfo imgInfo = imageLine.ImgInfo;
int numRows = imgInfo.Rows;
int numCols = imgInfo.Cols;
int bitDepth = imgInfo.BitDepth;
int channels = imgInfo.Channels;// int channels = 4;
float max = GetBitDepthMaxValue(bitDepth);
int[] paletteAlpha = trns.PaletteAlpha;
int numIndicesWithAlpha = paletteAlpha.Length;
if (imageLine.SampleType == ImageLine.ESampleType.BYTE)
{
byte[] scanline = imageLine.ScanlineB;
for (int col = 0; col < numCols; col++)
{
int index = scanline[col] & 0xFF;
RGB <int> rgb = plte.GetEntryRgb(index, col * channels);
RGBA <int> rgba = rgb.RGBA(index < numIndicesWithAlpha ? paletteAlpha[index] : 255);
pixels[IndexPngToTexture(row, col, numRows, numCols)] = RGBA.ToColor(rgba, max);
}
}
else
{
int[] scanline = imageLine.Scanline;
for (int col = 0; col < numCols; col++)
{
int index = scanline[col];
RGB <int> rgb = plte.GetEntryRgb(index, col * channels);
RGBA <int> rgba = rgb.RGBA(index < numIndicesWithAlpha ? paletteAlpha[index] : 255);
pixels[IndexPngToTexture(row, col, numRows, numCols)] = RGBA.ToColor(rgba, max);
}
}
}
/// <summary> Given an indexed line with a palette, unpacks as a RGB array </summary>
/// <param name="line"> ImageLine as returned from PngReader </param>
/// <param name="pal"> Palette chunk </param>
/// <param name="trns"> TRNS chunk (optional) </param>
/// <param name="buffer"> Preallocated array, optional </param>
/// <returns> R G B (one byte per sample) </returns>
public static int[] Palette2rgb(ImageLine line, Chunks.PngChunkPLTE pal, Chunks.PngChunkTRNS trns, int[] buffer)
{
int numCols = line.ImgInfo.Cols;
bool isalpha = trns != null;
int channels = isalpha ? 4 : 3;
int nsamples = numCols * channels;
if (buffer == null || buffer.Length < nsamples)
{
buffer = new int[nsamples];
}
if (line.SamplesUnpacked == false)
{
line = line.UnpackToNewImageLine();
}
int nindexesWithAlpha = trns != null ? trns.PaletteAlpha.Length : 0;
if (line.SampleType == Pngcs.ImageLine.ESampleType.BYTE)
{
var scanline = line.ScanlineB;
if (isalpha)
{
var paletteAlpha = trns.PaletteAlpha;
for (int col = 0; col < numCols; col++)
{
int index = scanline[col] & 0xFF;
pal.GetEntryRgb(index, buffer, col * channels);
int alpha = index < nindexesWithAlpha ? paletteAlpha[index] : 255;
buffer[col * channels + 3] = alpha;
}
}
else
{
for (int col = 0; col < numCols; col++)
{
int index = scanline[col] & 0xFF;
pal.GetEntryRgb(index, buffer, col * channels);
}
}
}
else
{
var scanline = line.Scanline;
if (isalpha)
{
var paletteAlpha = trns.PaletteAlpha;
for (int col = 0; col < numCols; col++)
{
int index = scanline[col];
pal.GetEntryRgb(index, buffer, col * channels);
int alpha = index < nindexesWithAlpha ? paletteAlpha[index] : 255;
buffer[col * channels + 3] = alpha;
}
}
else
{
for (int col = 0; col < numCols; col++)
{
int index = scanline[col];
pal.GetEntryRgb(index, buffer, col * channels);
}
}
}
return(buffer);
}
