protected virtual void RenderLoop (ISurface src, ISurface dst, Rectangle roi, CancellationToken token, IRenderProgress progress)
{
src.BeginUpdate ();
dst.BeginUpdate ();
OnBeginRender (src, dst, roi);
var completed_lines = new bool[roi.Height];
var last_completed_index = 0;
if (Settings.SingleThreaded || roi.Height <= 1) {
for (var y = roi.Y; y <= roi.Bottom; ++y) {
if (token.IsCancellationRequested)
return;
RenderLine (src, dst, new Rectangle (roi.X, y, roi.Width, 1));
completed_lines[y - roi.Top] = true;
if (progress != null) {
var last_y = FindLastCompletedLine (completed_lines, last_completed_index);
last_completed_index = last_y;
progress.CompletedRoi = new Rectangle (roi.X, roi.Y, roi.Width, last_y);
progress.PercentComplete = (float)last_y / (float)roi.Height;
}
}
} else {
ParallelExtensions.OrderedFor (roi.Y, roi.Bottom + 1, token, (y) => {
RenderLine (src, dst, new Rectangle (roi.X, y, roi.Width, 1));
completed_lines[y - roi.Top] = true;
if (progress != null) {
var last_y = FindLastCompletedLine (completed_lines, last_completed_index);
last_completed_index = last_y;
progress.CompletedRoi = new Rectangle (roi.X, roi.Y, roi.Width, last_y);
progress.PercentComplete = (float)last_y / (float)roi.Height;
}
});
}
src.EndUpdate ();
dst.EndUpdate ();
}