X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/4c51a665c649f7579fb39e62070cef4f66b3210d..b22a1070b3f2de8ef85d34a841b5230aa08db967:/interface/wx/dc.h?ds=inline diff --git a/interface/wx/dc.h b/interface/wx/dc.h index d3e8875f60..32b986bd1e 100644 --- a/interface/wx/dc.h +++ b/interface/wx/dc.h @@ -113,7 +113,7 @@ struct wxFontMetrics wxWidgets offers an alternative drawing API based on the modern drawing backends GDI+, CoreGraphics and Cairo. See wxGraphicsContext, wxGraphicsRenderer and related classes. There is also a wxGCDC linking the APIs by offering - the wxDC API ontop of a wxGraphicsContext. + the wxDC API on top of a wxGraphicsContext. wxDC is an abstract base class and cannot be created directly. Use wxPaintDC, wxClientDC, wxWindowDC, wxScreenDC, wxMemoryDC or @@ -153,9 +153,14 @@ struct wxFontMetrics @section dc_alpha_support Support for Transparency / Alpha Channel - On Mac OS X colours with alpha channel are supported. Instances of wxPen - or wxBrush that are built from wxColour use the colour's alpha values - when stroking or filling. + In general wxDC methods don't support alpha transparency and the alpha + component of wxColour is simply ignored and you need to use wxGraphicsContext + for full transparency support. There are, however, a few exceptions: first, + under Mac OS X colours with alpha channel are supported in all the normal + wxDC-derived classes as they use wxGraphicsContext internally. Second, + under all platforms wxSVGFileDC also fully supports alpha channel. In both + of these cases the instances of wxPen or wxBrush that are built from + wxColour use the colour's alpha values when stroking or filling. @library{wxcore}