public static void DrawAlphaImage(Graphics g, Image img, Rectangle rect, byte alpha)
{
var hdcDst = g.GetHdc();
var gSrc = Graphics.FromImage(img);
var hdcSrc = gSrc.GetHdc();
var blendFunction = new BlendFunction
{
BlendOp = (byte) BlendOperation.AcSrcOver,
BlendFlags = (byte) BlendFlags.Zero,
SourceConstantAlpha = alpha,
AlphaFormat = 0
};
// Only supported blend operation
// Documentation says put 0 here
// Constant alpha factor
// AlphaFormat.AC_SRC_ALPHA;
//!!blendFunction.AlphaFormat = (byte)AlphaFormat.AC_SRC_ALPHA;
DrawingAPI.AlphaBlend(hdcDst, rect.Left, rect.Top, rect.Width, rect.Height, hdcSrc,
0, 0, img.Width, img.Height, blendFunction);
g.ReleaseHdc(hdcDst); // Required cleanup to GetHdc()
gSrc.ReleaseHdc(hdcSrc); // Required cleanup to GetHdc()
}
public void PaintBackgroundAlpha(Graphics g, Rectangle rect, byte alpha)
{
//!! see _factory.CreateBitmapFromImage
var buffer = new Bitmap(rect.Width, rect.Height, System.Drawing.Imaging.PixelFormat.Format32bppRgb);
var buffergx = Graphics.FromImage(buffer);
var bufferRect = new Rectangle(0, 0, rect.Width, rect.Height);
if (_img == null) return;
var hdcBuffer = buffergx.GetHdc();
try
{
OpenNETCF.Drawing.Imaging.RECT imgRect = OpenNETCF.Drawing.Imaging.RECT.FromXYWH(
bufferRect.Left, bufferRect.Top, bufferRect.Width, bufferRect.Height);
_img.Draw(hdcBuffer, imgRect, null);
buffergx.ReleaseHdc(hdcBuffer);
}
catch
{ }
var hdcDst = g.GetHdc();
hdcBuffer = buffergx.GetHdc();
var blendFunction = new BlendFunction
{
BlendOp = (byte) BlendOperation.AcSrcOver,
BlendFlags = (byte) BlendFlags.Zero,
SourceConstantAlpha = alpha,
AlphaFormat = (byte) AlphaFormat.AcSrcAlpha
};
// Only supported blend operation
// Documentation says put 0 here
// Constant alpha factor
DrawingAPI.AlphaBlend(hdcDst, rect.Left, rect.Top, rect.Width, rect.Height, hdcBuffer,
0, 0, rect.Width, rect.Height, blendFunction);
g.ReleaseHdc(hdcDst); // Required cleanup to GetHdc()
buffergx.ReleaseHdc(hdcBuffer); // Required cleanup to GetHdc()
}
public void PaintBackgroundAlpha(Graphics g, Rectangle Rect, byte Alpha)
{
//!! see _factory.CreateBitmapFromImage
Bitmap buffer = new Bitmap(Rect.Width, Rect.Height, System.Drawing.Imaging.PixelFormat.Format32bppRgb);
Graphics buffergx = Graphics.FromImage(buffer);
IntPtr hdcBuffer;
Rectangle BufferRect = new Rectangle(0, 0, Rect.Width, Rect.Height);
if (_img != null)
{
hdcBuffer = buffergx.GetHdc();
try
{
OpenNETCF.Drawing.Imaging.RECT ImgRect = OpenNETCF.Drawing.Imaging.RECT.FromXYWH(
BufferRect.Left, BufferRect.Top, BufferRect.Width, BufferRect.Height);
_img.Draw(hdcBuffer, ImgRect, null);
buffergx.ReleaseHdc(hdcBuffer);
}
catch (Exception e) { }
IntPtr hdcDst = g.GetHdc();
hdcBuffer = buffergx.GetHdc();
BlendFunction blendFunction = new BlendFunction();
blendFunction.BlendOp = (byte)BlendOperation.AC_SRC_OVER; // Only supported blend operation
blendFunction.BlendFlags = (byte)BlendFlags.Zero; // Documentation says put 0 here
blendFunction.SourceConstantAlpha = Alpha; // Constant alpha factor
blendFunction.AlphaFormat = (byte)AlphaFormat.AC_SRC_ALPHA;
DrawingAPI.AlphaBlend(hdcDst, Rect.Left, Rect.Top, Rect.Width, Rect.Height, hdcBuffer,
0, 0, Rect.Width, Rect.Height, blendFunction);
g.ReleaseHdc(hdcDst); // Required cleanup to GetHdc()
buffergx.ReleaseHdc(hdcBuffer); // Required cleanup to GetHdc()
}
}
public static extern bool AlphaBlend(IntPtr hdcDest, Int32 nXDest, Int32 nYDest, Int32 nWidthDst, Int32 nHeightDst, IntPtr hdcSrc, Int32 nXSrc, Int32 nYSrc, Int32 nWidthSrc, Int32 nHeightSrc, BlendFunction blendFunction);
public static void DrawAlphaImage(Graphics g, Image Img, Rectangle Rect, byte Alpha)
{
IntPtr hdcDst = g.GetHdc();
Graphics gSrc = Graphics.FromImage(Img);
IntPtr hdcSrc = gSrc.GetHdc();
BlendFunction blendFunction = new BlendFunction();
blendFunction.BlendOp = (byte)BlendOperation.AC_SRC_OVER; // Only supported blend operation
blendFunction.BlendFlags = (byte)BlendFlags.Zero; // Documentation says put 0 here
blendFunction.SourceConstantAlpha = Alpha; // Constant alpha factor
blendFunction.AlphaFormat = (byte)0; // AlphaFormat.AC_SRC_ALPHA;
//!!blendFunction.AlphaFormat = (byte)AlphaFormat.AC_SRC_ALPHA;
DrawingAPI.AlphaBlend(hdcDst, Rect.Left, Rect.Top, Rect.Width, Rect.Height, hdcSrc,
0, 0, Img.Width, Img.Height, blendFunction);
g.ReleaseHdc(hdcDst); // Required cleanup to GetHdc()
gSrc.ReleaseHdc(hdcSrc); // Required cleanup to GetHdc()
}
