internal void DrawImageCore(Graphics g, Bitmap bmp, Rectangle srcRect, Rectangle destRect, float alpha)
{
if (alpha < 1)
{
var attr = new ImageAttributes ();
float[][] matrixItems = new[] {
new float[] { 1, 0, 0, 0, 0 },
new float[] { 0, 1, 0, 0, 0 },
new float[] { 0, 0, 1, 0, 0 },
new float[] { 0, 0, 0, alpha, 0 },
new float[] { 0, 0, 0, 0, 1 },
};
attr.SetColorMatrix (new ColorMatrix (matrixItems), ColorMatrixFlag.Default, ColorAdjustType.Bitmap);
PointF[] points = new PointF[3];
points[0] = new PointF ((float) destRect.X, (float) destRect.Y);
points[1] = new PointF ((float) (destRect.X + destRect.Width), (float) destRect.Y);
points[2] = new PointF ((float) destRect.X, (float) (destRect.Y + destRect.Height));
g.DrawImage (bmp, points, srcRect.ToSDRectF (), GraphicsUnit.Pixel, attr);
}
else
g.DrawImage (bmp, destRect.ToSDRectF (), srcRect.ToSDRectF (), GraphicsUnit.Pixel);
}
