/// <summary>
/// Function to persist image data to a stream.
/// </summary>
/// <param name="imageData"><see cref="GorgonLibrary.Graphics.GorgonImageData">Gorgon image data</see> to persist.</param>
/// <param name="stream">Stream that will contain the data.</param>
protected internal override void SaveToStream(GorgonImageData imageData, Stream stream)
{
// Use a binary writer.
using (var writer = new GorgonBinaryWriter(stream, true))
{
// Write the header for the file.
TGAConversionFlags conversionFlags;
WriteHeader(imageData.Settings, writer, out conversionFlags);
GorgonFormatPitch pitch;
if ((conversionFlags & TGAConversionFlags.RGB888) == TGAConversionFlags.RGB888)
{
pitch = new GorgonFormatPitch(imageData.Settings.Width * 3, imageData.Settings.Width * 3 * imageData.Settings.Height);
}
else
{
var formatInfo = GorgonBufferFormatInfo.GetInfo(imageData.Settings.Format);
pitch = formatInfo.GetPitch(imageData.Settings.Width, imageData.Settings.Height, PitchFlags.None);
}
// Get the pointer to the first mip/array/depth level.
var srcPointer = (byte *)imageData.Buffers[0].Data.UnsafePointer;
var srcPitch = imageData.Buffers[0].PitchInformation;
// If the two pitches are equal, then just write out the buffer.
if ((pitch == srcPitch) && (conversionFlags == TGAConversionFlags.None))
{
writer.Write(srcPointer, srcPitch.SlicePitch);
return;
}
// If we have to do a conversion, create a worker buffer.
using (var convertBuffer = new GorgonDataStream(pitch.SlicePitch))
{
var destPtr = (byte *)convertBuffer.UnsafePointer;
// Write out each scan line.
for (int y = 0; y < imageData.Settings.Height; y++)
{
if ((conversionFlags & TGAConversionFlags.RGB888) == TGAConversionFlags.RGB888)
{
Compress24BPPScanLine(srcPointer, srcPitch.RowPitch, destPtr, pitch.RowPitch);
}
else if ((conversionFlags & TGAConversionFlags.Swizzle) == TGAConversionFlags.Swizzle)
{
SwizzleScanline(srcPointer, srcPitch.RowPitch, destPtr, pitch.RowPitch, imageData.Settings.Format, ImageBitFlags.None);
}
else
{
CopyScanline(srcPointer, srcPitch.RowPitch, destPtr, pitch.RowPitch, imageData.Settings.Format, ImageBitFlags.None);
}
destPtr += pitch.RowPitch;
srcPointer += srcPitch.RowPitch;
}
// Persist to the stream.
writer.Write(convertBuffer.UnsafePointer, pitch.SlicePitch);
}
}
}
/// <summary>
/// Function to perform the copying of image data into the buffer.
/// </summary>
/// <param name="stream">Stream containing the image data.</param>
/// <param name="image">Image data.</param>
/// <param name="conversionFlags">Flags used to convert the image.</param>
private void CopyImageData(GorgonDataStream stream, GorgonImageData image, TGAConversionFlags conversionFlags)
{
var buffer = image.Buffers[0]; // Get the first buffer only.
var formatInfo = GorgonBufferFormatInfo.GetInfo(image.Settings.Format);
GorgonFormatPitch srcPitch = (conversionFlags & TGAConversionFlags.Expand) == TGAConversionFlags.Expand
? new GorgonFormatPitch(image.Settings.Width * 3, image.Settings.Width * 3 * image.Settings.Height)
: formatInfo.GetPitch(image.Settings.Width, image.Settings.Height, PitchFlags.None);
// Otherwise, allocate a buffer for conversion.
var srcPtr = (byte *)stream.PositionPointerUnsafe;
var destPtr = (byte *)buffer.Data.UnsafePointer;
// Adjust destination for inverted axes.
if ((conversionFlags & TGAConversionFlags.InvertX) == TGAConversionFlags.InvertX)
{
destPtr += buffer.PitchInformation.RowPitch - formatInfo.SizeInBytes;
}
if ((conversionFlags & TGAConversionFlags.InvertY) != TGAConversionFlags.InvertY)
{
destPtr += (image.Settings.Height - 1) * buffer.PitchInformation.RowPitch;
}
// Get bounds of image memory.
var scanSize = (int)(stream.Length - stream.Position);
byte *endScan = (byte *)stream.PositionPointerUnsafe + scanSize;
int opaqueLineCount = 0;
for (int y = 0; y < image.Settings.Height; y++)
{
bool setOpaque;
if ((conversionFlags & TGAConversionFlags.RLE) == TGAConversionFlags.RLE)
{
setOpaque = ReadCompressed(ref srcPtr, image.Settings.Width, destPtr, endScan, image.Settings.Format, conversionFlags);
}
else
{
setOpaque = ReadUncompressed(srcPtr, srcPitch.RowPitch, destPtr, image.Settings.Format, conversionFlags);
srcPtr += srcPitch.RowPitch;
}
if ((setOpaque) && (SetOpaqueIfZeroAlpha))
{
opaqueLineCount++;
}
if ((conversionFlags & TGAConversionFlags.InvertY) != TGAConversionFlags.InvertY)
{
destPtr -= buffer.PitchInformation.RowPitch;
}
else
{
destPtr += buffer.PitchInformation.RowPitch;
}
}
if (opaqueLineCount != image.Settings.Height)
{
return;
}
// Set the alpha to opaque if we don't have any alpha values (i.e. alpha = 0 for all pixels).
destPtr = (byte *)buffer.Data.UnsafePointer;
for (int y = 0; y < image.Settings.Height; y++)
{
CopyScanline(destPtr, buffer.PitchInformation.RowPitch, destPtr, buffer.PitchInformation.RowPitch, image.Settings.Format, ImageBitFlags.OpaqueAlpha);
destPtr += buffer.PitchInformation.RowPitch;
}
}