private void OnRenderProgress(RenderProgressStep progressStep)
{
if (_bitmap == null)
{
throw new InvalidOperationException("Shouldn't be reporting progress when nothing is rendering.");
}
UpdateBitmap(progressStep);
ReportProgress(progressStep.PercentComplete);
}
/// <summary>
/// Updates the bitmap with the cached updates.
/// </summary>
/// <param name="renderProgressStep">The update containing which pixels to set.</param>
private void UpdateBitmap(RenderProgressStep renderProgressStep)
{
if (_bitmap == null)
{
throw new InvalidOperationException("Should not be processing updates when the bitmap is null.");
}
// Lock the bitmap so that we can do all of the updates at once.
_bitmap.Lock();
try
{
int bytesPerPixel = _bitmap.Format.BitsPerPixel / 8;
// Get a pointer to the back buffer for the corresponding row.
IntPtr backBuffer = _bitmap.BackBuffer + (renderProgressStep.Row * _bitmap.BackBufferStride);
// Loop through each pixel in the render progress step and set the corresponding color in the bitmap.
foreach (Color color in renderProgressStep.Pixels)
{
// Convert the pixel's color to rgb format.
int rgb = color.ToRgb();
// Set the pixel in memory
unsafe
{
*(int *)backBuffer = rgb;
}
// Increment the buffer pointer
backBuffer += bytesPerPixel;
}
// Calculate the update rectangle for the bitmap.
var rect = new Int32Rect(0, renderProgressStep.Row, _bitmap.PixelWidth, 1);
// Tell the bitmap what changed.
_bitmap.AddDirtyRect(rect);
}
finally
{
// Unlock the bitmap so that it can be displayed in the UI.
_bitmap.Unlock();
}
}
