Is alpha transparent supported in NewPagFromCanvDC

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Hi, I am tring to use gdiplus create a transparent brush. The NewPageFromCanvasDC can't fill if the Color alpha value <255.
Codes:
HDC dc = QP.GetCanvasDC(1000,800);
Graphics myGraphics(dc);
Color colors[] = {
      Color(255, 255, 0, 0),   // red
      Color(155, 0, 0, 255),   // blue
      Color(55, 0, 255, 0)};  // green
REAL positions[] = {  0.0f,     0.3f,   1.0f};
LinearGradientBrush linGrBrush3( Point(0, 0), Point(300, 0),Color(255, 0, 0, 0),  Color(255, 255, 255, 255));
linGrBrush3.SetInterpolationColors(colors, positions, 3); 
myGraphics.FillRectangle(&linGrBrush3, 220, 220, 500, 650);
QP.NewPageFromCanvasDC(300, -1);

Can anyone help me? Thanks.

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cathyling Members Profile Find Members Posts Beginner Joined: 17 Sep 13 Status: Offline Points: 2	Post Options Post Reply Quote cathyling Report Post Thanks(0) Quote Reply Topic: Is alpha transparent supported in NewPagFromCanvDC Posted: 17 Sep 13 at 4:37PM
	Hi, I am tring to use gdiplus create a transparent brush. The NewPageFromCanvasDC can't fill if the Color alpha value <255. Codes: HDC dc = QP.GetCanvasDC(1000,800); Graphics myGraphics(dc); Color colors[] = { Color(255, 255, 0, 0), // red Color(155, 0, 0, 255), // blue Color(55, 0, 255, 0)}; // green REAL positions[] = { 0.0f, 0.3f, 1.0f}; LinearGradientBrush linGrBrush3( Point(0, 0), Point(300, 0),Color(255, 0, 0, 0), Color(255, 255, 255, 255)); linGrBrush3.SetInterpolationColors(colors, positions, 3); myGraphics.FillRectangle(&linGrBrush3, 220, 220, 500, 650); QP.NewPageFromCanvasDC(300, -1); Can anyone help me? Thanks.

AndrewC Members Profile Find Members Posts Moderator Group Joined: 08 Dec 10 Location: Geelong, Aust Status: Offline Points: 841	Post Options Post Reply Quote AndrewC Report Post Thanks(0) Quote Reply Posted: 18 Sep 13 at 4:48AM
	cathylin, I have had a quick look at the source code. The Gradient fills are supported but brush transparency is not supported. This could get quite complex to implement as it is not always easy to map GDI+ calls to PDF. I will add it to the todo list for the GDI+ metafile code. Andrew.