public static void setPixel(this System.Windows.Media.Imaging.WriteableBitmap wbm, int x, int y, System.Windows.Media.Color c)
{
if (y > wbm.PixelHeight - 1 || x > wbm.PixelWidth - 1)
return;
if (y < 0 || x < 0)
return;
wbm.Pixels[y * wbm.PixelWidth + x] = c.A << 24 | c.R << 16 | c.G << 8 | c.B;
}