X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/8b93348e82c0906364ef2e020fd1adaaa49f519f..1b7751aaa9a86d76a850b9267bc0c201e3cea30f:/interface/wx/dcmemory.h diff --git a/interface/wx/dcmemory.h b/interface/wx/dcmemory.h index 0d21e5bb0b..100fc9beea 100644 --- a/interface/wx/dcmemory.h +++ b/interface/wx/dcmemory.h @@ -3,7 +3,7 @@ // Purpose: interface of wxMemoryDC // Author: wxWidgets team // RCS-ID: $Id$ -// Licence: wxWindows license +// Licence: wxWindows licence ///////////////////////////////////////////////////////////////////////////// /** @@ -55,6 +55,18 @@ public: a bitmap into the DC before drawing on it. */ wxMemoryDC(); + + /** + Constructs a new memory device context having the same characteristics + as the given existing device context. + + This constructor creates a memory device context @e compatible with @a + dc in wxMSW, the argument is ignored in the other ports. If @a dc is + @NULL, a device context compatible with the screen is created, just as + with the default constructor. + */ + wxMemoryDC(wxDC *dc); + /** Constructs a new memory device context and calls SelectObject() with the given bitmap. @@ -69,13 +81,17 @@ public: should use when you select a bitmap because you want to modify it, e.g. drawing on this DC. - Using SelectObjectAsSource() when modifying the bitmap may incurr some + Using SelectObjectAsSource() when modifying the bitmap may incur some problems related to wxBitmap being a reference counted object (see @ref overview_refcount). - Also, before using the updated bitmap data, make sure to select it out - of context first (for example by selecting ::wxNullBitmap into the device - context). + Before using the updated bitmap data, make sure to select it out of + context first either by selecting ::wxNullBitmap into the device + context or destroying the device context entirely. + + If the bitmap is already selected in this device context, nothing is + done. If it is selected in another context, the function asserts and + drawing on the bitmap won't work correctly. @see wxDC::DrawBitmap() */