wxWidgets Discussion Forum

Posted: **Thu May 25, 2017 4:38 pm**

Hello,
I believe wxPDF is only using operation raster wxCOPY and not heeding the dc->SetLogicalFunction call. Would this be an easy fix? In the code below, dc is a wxPdfDC.

Code: Select all

 dc->SetLogicalFunction(wxOR);

Thanks,

Ed

Posted: **Fri May 26, 2017 9:05 am**

ees wrote:I believe wxPDF is only using operation raster wxCOPY and not heeding the dc->SetLogicalFunction call. Would this be an easy fix? In the code below, dc is a wxPdfDC.
Code: Select all
 dc->SetLogicalFunction(wxOR);

PDF is not a raster format, but a vector format. Therefore raster oriented operations are usually of limited use.

wxPdfDC supports 2 modes for the logical function: wxCOPY (the default) and wxAND (using alpha transparency).

The PDF specification contains special blending modes that could probably be used to map some or even all of a DC's logical functions. However, wxPdfDocument currently has no support for those special blending modes. And - to be frank - I currently don't intend to add such support myself.

Of course, you are welcome to contribute support for those special blending modes to wxPdfDocument, if you have a high demand for it.

Regards,

Ulrich

wxWidgets Discussion Forum

wxPDF only using raster operation wxCOPY

wxPDF only using raster operation wxCOPY

Re: wxPDF only using raster operation wxCOPY