From e3b81044ee30ead362ba6e1bf95af13248afe41c Mon Sep 17 00:00:00 2001
From: Vadim Zeitlin <vadim@wxwidgets.org>
Date: Sun, 18 Mar 2007 15:32:27 +0000
Subject: [PATCH] wxDC::StretchBlit() for wxMac and wxMSW (patch 1611973)

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@44892 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
---
 docs/changes.txt            |   1 +
 docs/latex/wx/dc.tex        |  83 +++++++++++++++++++++-
 include/wx/dc.h             |  44 ++++++++++--
 include/wx/dcgraph.h        |   8 +++
 include/wx/mac/carbon/dc.h  |   8 +++
 include/wx/msw/dc.h         |   8 +++
 samples/drawing/drawing.cpp |  58 +++++++++++-----
 src/common/dcbase.cpp       |  27 +++++++-
 src/common/dcgraph.cpp      |  24 +++++--
 src/mac/carbon/dc.cpp       |  28 ++++++--
 src/mac/carbon/dccg.cpp     |  26 +++++--
 src/msw/dc.cpp              | 134 +++++++++++++++++++++---------------
 12 files changed, 348 insertions(+), 101 deletions(-)

diff --git a/docs/changes.txt b/docs/changes.txt
index 212e6e800c..4fe7ed481b 100644
--- a/docs/changes.txt
+++ b/docs/changes.txt
@@ -65,6 +65,7 @@ All:
 
 All (GUI):
 
+- Added wxDC::StretchBlit() for wxMac and wxMSW (Vince Harron)
 - Added wxEventBlocker class (Francesco Montorsi).
 - Added wxFile/DirPickerCtrl::Get/SetFile/DirName() (Francesco Montorsi).
 - Added wxSizerFlags::Top() and Bottom().
diff --git a/docs/latex/wx/dc.tex b/docs/latex/wx/dc.tex
index 5f57bfbac9..cffeac284a 100644
--- a/docs/latex/wx/dc.tex
+++ b/docs/latex/wx/dc.tex
@@ -108,7 +108,7 @@ See \helpref{wxMemoryDC}{wxmemorydc} for typical usage.
 
 \wxheading{See also}
 
-\helpref{wxMemoryDC}{wxmemorydc}, \helpref{wxBitmap}{wxbitmap}, \helpref{wxMask}{wxmask}
+\helpref{wxDC::StretchBlit}{wxdcstretchblit}, \helpref{wxMemoryDC}{wxmemorydc}, \helpref{wxBitmap}{wxbitmap}, \helpref{wxMask}{wxmask}
 
 \begin{comment}
 
@@ -1198,3 +1198,84 @@ Message is a message to show while printing.
 
 Starts a document page (only relevant when outputting to a printer).
 
+
+\membersection{wxDC::StretchBlit}\label{wxdcstretchblit}
+
+\func{bool}{StretchBlit}{\param{wxCoord}{ xdest}, \param{wxCoord}{ ydest}, \param{wxCoord}{ dstWidth}, \param{wxCoord}{ dstHeight},
+  \param{wxDC* }{source}, \param{wxCoord}{ xsrc}, \param{wxCoord}{ ysrc}, \param{wxCoord}{ srcWidth}, \param{wxCoord}{ srcHeight}, 
+  \param{int}{ logicalFunc = wxCOPY}, \param{bool }{useMask = false}, \param{wxCoord}{ xsrcMask = -1}, \param{wxCoord}{ ysrcMask = -1}}
+
+Copy from a source DC to this DC, specifying the destination
+coordinates, destination size, source DC, source coordinates,
+size of source area to copy, logical function, whether to use a bitmap mask, 
+and mask source position.
+
+\wxheading{Parameters}
+
+\docparam{xdest}{Destination device context x position.}
+
+\docparam{ydest}{Destination device context y position.}
+
+\docparam{dstWidth}{Width of destination area.}
+
+\docparam{dstHeight}{Height of destination area.}
+
+\docparam{source}{Source device context.}
+
+\docparam{xsrc}{Source device context x position.}
+
+\docparam{ysrc}{Source device context y position.}
+
+\docparam{srcWidth}{Width of source area to be copied.}
+
+\docparam{srcHeight}{Height of source area to be copied.}
+
+\docparam{logicalFunc}{Logical function to use: see \helpref{wxDC::SetLogicalFunction}{wxdcsetlogicalfunction}.}
+
+\docparam{useMask}{If true, Blit does a transparent blit using the mask that is associated with the bitmap
+selected into the source device context. The Windows implementation does the following if \texttt{MaskBlt} cannot be used:
+
+\begin{enumerate}
+\item Creates a temporary bitmap and copies the destination area into it.
+\item Copies the source area into the temporary bitmap using the specified logical function.
+\item Sets the masked area in the temporary bitmap to BLACK by ANDing the
+mask bitmap with the temp bitmap with the foreground colour set to WHITE
+and the background colour set to BLACK.
+\item Sets the unmasked area in the destination area to BLACK by ANDing the
+mask bitmap with the destination area with the foreground colour set to BLACK
+and the background colour set to WHITE.
+\item ORs the temporary bitmap with the destination area.
+\item Deletes the temporary bitmap.
+\end{enumerate}
+
+This sequence of operations ensures that the source's transparent area need not be black,
+and logical functions are supported.
+
+{\bf Note:} on Windows, blitting with masks can be speeded up considerably by compiling
+wxWidgets with the \texttt{wxUSE\_DC\_CACHE} option enabled. You can also influence whether \texttt{MaskBlt}
+or the explicit mask blitting code above is used, by using \helpref{wxSystemOptions}{wxsystemoptions} and
+setting the {\bf no-maskblt} option to 1.
+
+}
+
+\docparam{xsrcMask}{Source x position on the mask. If both xsrcMask and ysrcMask are -1, xsrc and ysrc
+will be assumed for the mask source position. Currently only implemented on Windows.}
+
+\docparam{ysrcMask}{Source y position on the mask. If both xsrcMask and ysrcMask are -1, xsrc and ysrc
+will be assumed for the mask source position. Currently only implemented on Windows.}
+
+
+\wxheading{Remarks}
+
+There is partial support for Blit in wxPostScriptDC, under X.
+
+wxDC::StretchBlit is only implemented under wxMAC and wxMSW.
+
+See \helpref{wxMemoryDC}{wxmemorydc} for typical usage.
+
+\newsince{2.9.0}
+
+\wxheading{See also}
+
+\helpref{wxDC::Blit}{wxdcblit}, \helpref{wxMemoryDC}{wxmemorydc}, \helpref{wxBitmap}{wxbitmap}, \helpref{wxMask}{wxmask}
+
diff --git a/include/wx/dc.h b/include/wx/dc.h
index 67fd8f48c8..a846442f68 100644
--- a/include/wx/dc.h
+++ b/include/wx/dc.h
@@ -313,7 +313,26 @@ public:
         return DoBlit(destPt.x, destPt.y, sz.x, sz.y,
                       source, srcPt.x, srcPt.y, rop, useMask, srcPtMask.x, srcPtMask.y);
     }
-    
+
+    bool StretchBlit(wxCoord dstX, wxCoord dstY, 
+                     wxCoord dstWidth, wxCoord dstHeight,
+                     wxDC *source, 
+                     wxCoord srcX, wxCoord srcY,
+                     wxCoord srcWidth, wxCoord srcHeight,
+                     int rop = wxCOPY, bool useMask = false, 
+                     wxCoord srcMaskX = wxDefaultCoord, wxCoord srcMaskY = wxDefaultCoord)
+    {
+        return DoStretchBlit(dstX, dstY, dstWidth, dstHeight,
+                      source, srcX, srcY, srcWidth, srcHeight, rop, useMask, srcMaskX, srcMaskY);
+    }
+    bool StretchBlit(const wxPoint& dstPt, const wxSize& dstSize,
+                     wxDC *source, const wxPoint& srcPt, const wxSize& srcSize,
+                     int rop = wxCOPY, bool useMask = false, const wxPoint& srcMaskPt = wxDefaultPosition)
+    {
+        return DoStretchBlit(dstPt.x, dstPt.y, dstSize.x, dstSize.y,
+                      source, srcPt.x, srcPt.y, srcSize.x, srcSize.y, rop, useMask, srcMaskPt.x, srcMaskPt.y);
+    }
+
     wxBitmap GetAsBitmap(const wxRect *subrect = (const wxRect *) NULL) const
     {
         return DoGetAsBitmap(subrect);
@@ -723,10 +742,25 @@ protected:
 
     virtual bool DoBlit(wxCoord xdest, wxCoord ydest,
                         wxCoord width, wxCoord height,
-                        wxDC *source, wxCoord xsrc, wxCoord ysrc,
-                        int rop = wxCOPY, bool useMask = false, wxCoord xsrcMask = wxDefaultCoord, wxCoord ysrcMask = wxDefaultCoord) = 0;
-
-    virtual wxBitmap DoGetAsBitmap(const wxRect *WXUNUSED(subrect)) const { return wxNullBitmap; }
+                        wxDC *source,
+                        wxCoord xsrc, wxCoord ysrc,
+                        int rop = wxCOPY,
+                        bool useMask = false,
+                        wxCoord xsrcMask = wxDefaultCoord,
+                        wxCoord ysrcMask = wxDefaultCoord) = 0;
+
+    virtual bool DoStretchBlit(wxCoord xdest, wxCoord ydest,
+                               wxCoord dstWidth, wxCoord dstHeight,
+                               wxDC *source,
+                               wxCoord xsrc, wxCoord ysrc,
+                               wxCoord srcWidth, wxCoord srcHeight,
+                               int rop = wxCOPY,
+                               bool useMask = false,
+                               wxCoord xsrcMask = wxDefaultCoord,
+                               wxCoord ysrcMask = wxDefaultCoord);
+
+    virtual wxBitmap DoGetAsBitmap(const wxRect *WXUNUSED(subrect)) const
+        { return wxNullBitmap; }
 
     virtual void DoGetSize(int *width, int *height) const = 0;
     virtual void DoGetSizeMM(int* width, int* height) const = 0;
diff --git a/include/wx/dcgraph.h b/include/wx/dcgraph.h
index 9115ec0af4..35fd3f9b14 100755
--- a/include/wx/dcgraph.h
+++ b/include/wx/dcgraph.h
@@ -145,6 +145,14 @@ protected:
         wxDC *source, wxCoord xsrc, wxCoord ysrc,
         int rop = wxCOPY, bool useMask = false, wxCoord xsrcMask = -1, wxCoord ysrcMask = -1);
 
+    virtual bool DoStretchBlit(wxCoord xdest, wxCoord ydest,
+                               wxCoord dstWidth, wxCoord dstHeight,
+                               wxDC *source,
+                               wxCoord xsrc, wxCoord ysrc,
+                               wxCoord srcWidth, wxCoord srcHeight,
+                               int rop = wxCOPY, bool useMask = false,
+                               wxCoord xsrcMask = wxDefaultCoord, wxCoord ysrcMask = wxDefaultCoord);
+
     virtual void DoGetSize(int *,int *) const;
     virtual void DoGetSizeMM(int* width, int* height) const;
 
diff --git a/include/wx/mac/carbon/dc.h b/include/wx/mac/carbon/dc.h
index 161997dd71..b0e83d67d2 100644
--- a/include/wx/mac/carbon/dc.h
+++ b/include/wx/mac/carbon/dc.h
@@ -255,6 +255,14 @@ protected:
                         wxDC *source, wxCoord xsrc, wxCoord ysrc,
                         int rop = wxCOPY, bool useMask = false, wxCoord xsrcMask = -1, wxCoord ysrcMask = -1);
 
+    virtual bool DoStretchBlit(wxCoord xdest, wxCoord ydest,
+                               wxCoord dstWidth, wxCoord dstHeight,
+                               wxDC *source,
+                               wxCoord xsrc, wxCoord ysrc,
+                               wxCoord srcWidth, wxCoord srcHeight,
+                               int rop = wxCOPY, bool useMask = false,
+                               wxCoord xsrcMask = wxDefaultCoord, wxCoord ysrcMask = wxDefaultCoord);
+
     // this is gnarly - we can't even call this function DoSetClippingRegion()
     // because of virtual function hiding
 
diff --git a/include/wx/msw/dc.h b/include/wx/msw/dc.h
index 0ab2cc622e..9e6f7fcab8 100644
--- a/include/wx/msw/dc.h
+++ b/include/wx/msw/dc.h
@@ -214,6 +214,14 @@ protected:
                         wxDC *source, wxCoord xsrc, wxCoord ysrc,
                         int rop = wxCOPY, bool useMask = false, wxCoord xsrcMask = wxDefaultCoord, wxCoord ysrcMask = wxDefaultCoord);
 
+    virtual bool DoStretchBlit(wxCoord xdest, wxCoord ydest,
+                               wxCoord dstWidth, wxCoord dstHeight,
+                               wxDC *source,
+                               wxCoord xsrc, wxCoord ysrc,
+                               wxCoord srcWidth, wxCoord srcHeight,
+                               int rop = wxCOPY, bool useMask = false,
+                               wxCoord xsrcMask = wxDefaultCoord, wxCoord ysrcMask = wxDefaultCoord);
+
     // this is gnarly - we can't even call this function DoSetClippingRegion()
     // because of virtual function hiding
     virtual void DoSetClippingRegionAsRegion(const wxRegion& region);
diff --git a/samples/drawing/drawing.cpp b/samples/drawing/drawing.cpp
index 95fadd09ba..2c217f8826 100644
--- a/samples/drawing/drawing.cpp
+++ b/samples/drawing/drawing.cpp
@@ -70,6 +70,7 @@ enum ScreenToShow
     Show_Brushes,
     Show_Polygons,
     Show_Mask,
+    Show_Mask_Stretch,
     Show_Ops,
     Show_Regions,
     Show_Circles,
@@ -178,11 +179,17 @@ public:
 #endif
 
 protected:
+    enum DrawMode
+    {
+        Draw_Normal,
+        Draw_Stretch
+    };
+
     void DrawTestLines( int x, int y, int width, wxDC &dc );
     void DrawTestPoly(wxDC& dc);
     void DrawTestBrushes(wxDC& dc);
     void DrawText(wxDC& dc);
-    void DrawImages(wxDC& dc);
+    void DrawImages(wxDC& dc, DrawMode mode);
     void DrawWithLogicalOps(wxDC& dc);
 #if wxUSE_GRAPHICS_CONTEXT
     void DrawAlpha(wxDC& dc);
@@ -227,6 +234,7 @@ enum
     File_ShowBrushes,
     File_ShowPolygons,
     File_ShowMask,
+    File_ShowMaskStretch,
     File_ShowOps,
     File_ShowRegions,
     File_ShowCircles,
@@ -310,6 +318,7 @@ bool MyApp::LoadImages()
     wxPathList pathList;
     pathList.Add(_T("."));
     pathList.Add(_T(".."));
+    pathList.Add(_T("../.."));
 
     wxString path = pathList.FindValidPath(_T("pat4.bmp"));
     if ( !path )
@@ -835,7 +844,7 @@ static const struct
     { wxT("wxXOR"),          wxXOR           },
 };
 
-void MyCanvas::DrawImages(wxDC& dc)
+void MyCanvas::DrawImages(wxDC& dc, DrawMode mode)
 {
     dc.DrawText(_T("original image"), 0, 0);
     dc.DrawBitmap(*gs_bmpNoMask, 0, 20, 0);
@@ -857,7 +866,15 @@ void MyCanvas::DrawImages(wxDC& dc)
 
         dc.DrawText(rasterOperations[n].name, x, y - 20);
         memDC.SelectObject(*gs_bmpWithColMask);
-        dc.Blit(x, y, cx, cy, &memDC, 0, 0, rasterOperations[n].rop, true);
+        if ( mode == Draw_Stretch )
+        {
+            dc.StretchBlit(x, y, cx, cy, &memDC, 0, 0, cx/2, cy/2,
+                           rasterOperations[n].rop, true);
+        }
+        else
+        {
+            dc.Blit(x, y, cx, cy, &memDC, 0, 0, rasterOperations[n].rop, true);
+        }
     }
 }
 
@@ -912,32 +929,32 @@ void MyCanvas::DrawAlpha(wxDC& dc)
     wxDouble margin = 20 ;
     wxDouble width = 180 ;
     wxDouble radius = 30 ;
-    
+
     dc.SetPen( wxPen( wxColour( 128, 0, 0, 255 ),12, wxSOLID));
     dc.SetBrush( wxBrush( wxColour( 255, 0, 0, 255),wxSOLID));
-    
+
     wxRect r(margin,margin+width*0.66,width,width) ;
-    
+
     dc.DrawRoundedRectangle( r.x, r.y, r.width, r.width, radius ) ;
-    
+
     dc.SetPen( wxPen( wxColour( 0, 0, 128, 255 ),12, wxSOLID));
     dc.SetBrush( wxBrush( wxColour( 0, 0, 255, 255),wxSOLID));
-    
+
     r.Offset( width * 0.8 , - width * 0.66 ) ;
-    
+
     dc.DrawRoundedRectangle( r.x, r.y, r.width, r.width, radius ) ;
-    
+
     dc.SetPen( wxPen( wxColour( 128, 128, 0, 255 ),12, wxSOLID));
     dc.SetBrush( wxBrush( wxColour( 192, 192, 0, 255),wxSOLID));
 
     r.Offset( width * 0.8 , width *0.5 ) ;
-    
+
     dc.DrawRoundedRectangle( r.x, r.y, r.width, r.width, radius ) ;
-    
+
     dc.SetPen( *wxTRANSPARENT_PEN ) ;
     dc.SetBrush( wxBrush( wxColour(255,255,128,128) ) );
     dc.DrawRoundedRectangle( 0 , margin + width / 2 , width * 3 , 100 , radius) ;
-    
+
     dc.SetTextForeground( wxColour(255,255,0,128) );
     dc.SetFont( wxFont( 40, wxFONTFAMILY_SWISS, wxFONTSTYLE_ITALIC, wxFONTWEIGHT_NORMAL ) );
     dc.DrawText( wxT("Hello!"), 120, 80 );
@@ -976,9 +993,9 @@ void MyCanvas::DrawCircles(wxDC& dc)
     dc.DrawEllipticArc(x + r, y, 2*r, r, 90, 180);
     dc.DrawEllipticArc(x + 3*r, y, 2*r, r, 180, 270);
     dc.DrawEllipticArc(x + 5*r, y, 2*r, r, 270, 360);
-    
+
     // same as above, just transparent brush
-    
+
     dc.SetPen( *wxRED_PEN );
     dc.SetBrush( *wxTRANSPARENT_BRUSH );
 
@@ -1005,7 +1022,7 @@ void MyCanvas::DrawCircles(wxDC& dc)
     dc.DrawEllipticArc(x + r, y, 2*r, r, 90, 180);
     dc.DrawEllipticArc(x + 3*r, y, 2*r, r, 180, 270);
     dc.DrawEllipticArc(x + 5*r, y, 2*r, r, 270, 360);
-    
+
 }
 
 void MyCanvas::DrawSplines(wxDC& dc)
@@ -1280,13 +1297,17 @@ void MyCanvas::OnPaint(wxPaintEvent &WXUNUSED(event))
             break;
 
         case Show_Mask:
-            DrawImages(dc);
+            DrawImages(dc, Draw_Normal);
+            break;
+
+        case Show_Mask_Stretch:
+            DrawImages(dc, Draw_Stretch);
             break;
 
         case Show_Ops:
             DrawWithLogicalOps(dc);
             break;
-        
+
 #if wxUSE_GRAPHICS_CONTEXT
         case Show_Alpha:
             DrawAlpha(dc);
@@ -1355,6 +1376,7 @@ MyFrame::MyFrame(const wxString& title, const wxPoint& pos, const wxSize& size)
     menuFile->Append(File_ShowBrushes, _T("&Brushes screen\tF4"));
     menuFile->Append(File_ShowPolygons, _T("&Polygons screen\tF5"));
     menuFile->Append(File_ShowMask, _T("&Mask screen\tF6"));
+    menuFile->Append(File_ShowMaskStretch, _T("1/&2 scaled mask\tShift-F6"));
     menuFile->Append(File_ShowOps, _T("&ROP screen\tF7"));
     menuFile->Append(File_ShowRegions, _T("Re&gions screen\tF8"));
     menuFile->Append(File_ShowCircles, _T("&Circles screen\tF9"));
diff --git a/src/common/dcbase.cpp b/src/common/dcbase.cpp
index 9cffc3896a..0bdd8d06ef 100644
--- a/src/common/dcbase.cpp
+++ b/src/common/dcbase.cpp
@@ -78,6 +78,27 @@ void wxDCBase::DoDrawCheckMark(wxCoord x1, wxCoord y1,
     CalcBoundingBox(x2, y2);
 }
 
+// ----------------------------------------------------------------------------
+// stubs for functions not implemented in all ports
+// ----------------------------------------------------------------------------
+
+bool
+wxDCBase::DoStretchBlit(wxCoord xdest, wxCoord ydest,
+                        wxCoord dstWidth, wxCoord dstHeight,
+                        wxDC *source,
+                        wxCoord xsrc, wxCoord ysrc,
+                        wxCoord WXUNUSED(srcWidth), wxCoord WXUNUSED(srcHeight),
+                        int rop,
+                        bool useMask,
+                        wxCoord xsrcMask,
+                        wxCoord ysrcMask)
+{
+    // temporary default implementation to avoid breaking platforms that don't
+    // have DoStretchBlit
+    return DoBlit(xdest, ydest, dstWidth, dstHeight, source,
+                  xsrc, ysrc, rop, useMask, xsrcMask, ysrcMask);
+}
+
 // ----------------------------------------------------------------------------
 // line/polygons
 // ----------------------------------------------------------------------------
@@ -734,7 +755,7 @@ void wxDCBase::DoGradientFillLinear(const wxRect& rect,
             else
                 nB = nB1 + (nB2-nB1)*(w-x)/w;
 
-	    wxColour colour(nR,nG,nB);
+            wxColour colour(nR,nG,nB);
             SetPen(wxPen(colour, 1, wxSOLID));
             SetBrush(wxBrush(colour));
             if(nDirection == wxEAST)
@@ -771,7 +792,7 @@ void wxDCBase::DoGradientFillLinear(const wxRect& rect,
             else
                 nB = nB1 + (nB2-nB1)*(w-y)/w;
 
-	    wxColour colour(nR,nG,nB);
+            wxColour colour(nR,nG,nB);
             SetPen(wxPen(colour, 1, wxSOLID));
             SetBrush(wxBrush(colour));
             if(nDirection == wxNORTH)
@@ -1156,4 +1177,4 @@ void wxDCBase::CalculateEllipticPoints( wxList* points,
     } // not iUseAngles
 } // CalculateEllipticPoints
 
-#endif
+#endif // __WXWINCE__
diff --git a/src/common/dcgraph.cpp b/src/common/dcgraph.cpp
index 993cccf3db..40ff9d38d9 100644
--- a/src/common/dcgraph.cpp
+++ b/src/common/dcgraph.cpp
@@ -718,11 +718,22 @@ bool wxGCDC::CanDrawBitmap() const
 
 bool wxGCDC::DoBlit(
     wxCoord xdest, wxCoord ydest, wxCoord width, wxCoord height,
-    wxDC *source, wxCoord xsrc, wxCoord ysrc, int logical_func , bool WXUNUSED(useMask),
+    wxDC *source, wxCoord xsrc, wxCoord ysrc, int logical_func , bool useMask,
     wxCoord xsrcMask, wxCoord ysrcMask )
 {
-    wxCHECK_MSG( Ok(), false, wxT("wxGCDC(cg)::DoBlit - invalid DC") );
-    wxCHECK_MSG( source->Ok(), false, wxT("wxGCDC(cg)::DoBlit - invalid source DC") );
+    return DoStretchBlit( xdest, ydest, width, height,
+        source, xsrc, ysrc, width, height, logical_func, useMask,
+        xsrcMask,ysrcMask );
+}
+
+bool wxGCDC::DoStretchBlit(
+    wxCoord xdest, wxCoord ydest, wxCoord dstWidth, wxCoord dstHeight,
+    wxDC *source, wxCoord xsrc, wxCoord ysrc, wxCoord srcWidth, wxCoord srcHeight,
+    int logical_func , bool WXUNUSED(useMask),
+    wxCoord xsrcMask, wxCoord ysrcMask )
+{
+    wxCHECK_MSG( Ok(), false, wxT("wxGCDC(cg)::DoStretchBlit - invalid DC") );
+    wxCHECK_MSG( source->Ok(), false, wxT("wxGCDC(cg)::DoStretchBlit - invalid source DC") );
 
     if ( logical_func == wxNO_OP )
         return true;
@@ -740,8 +751,8 @@ bool wxGCDC::DoBlit(
 
     wxRect subrect(source->LogicalToDeviceX(xsrc),
                    source->LogicalToDeviceY(ysrc),
-                   source->LogicalToDeviceXRel(width),
-                   source->LogicalToDeviceYRel(height));
+                   source->LogicalToDeviceXRel(srcWidth),
+                   source->LogicalToDeviceYRel(srcHeight));
 
     // if needed clip the subrect down to the size of the source DC
     wxCoord sw, sh;
@@ -758,8 +769,7 @@ bool wxGCDC::DoBlit(
     if ( blit.Ok() )
     {
         m_graphicContext->DrawBitmap( blit, xdest, ydest,
-                                      wxMin(width, blit.GetWidth()),
-                                      wxMin(height, blit.GetHeight()));
+                                      dstWidth, dstHeight);
     }
     else
     {
diff --git a/src/mac/carbon/dc.cpp b/src/mac/carbon/dc.cpp
index 6ead8a9bbc..9a789f821f 100644
--- a/src/mac/carbon/dc.cpp
+++ b/src/mac/carbon/dc.cpp
@@ -1175,12 +1175,26 @@ bool wxDC::CanDrawBitmap(void) const
     return true ;
 }
 
-bool wxDC::DoBlit(wxCoord xdest, wxCoord ydest, wxCoord width, wxCoord height,
+bool wxDC::DoBlit(wxCoord xdest, wxCoord ydest, wxCoord dstWidth, wxCoord dstHeight,
                    wxDC *source, wxCoord xsrc, wxCoord ysrc, int logical_func , bool useMask,
                    wxCoord xsrcMask, wxCoord ysrcMask )
 {
-    wxCHECK_MSG(Ok(), false, wxT("wxDC::DoBlit - invalid DC"));
-    wxCHECK_MSG(source->Ok(), false, wxT("wxDC::DoBlit - invalid source DC"));
+    return DoStretchBlit( xdest, ydest, dstWidth, dstHeight,
+                           source, xsrc, ysrc, dstWidth, dstHeight, 
+                           logical_func, useMask,
+                           xsrcMask, ysrcMask );
+}
+
+bool wxDC::DoStretchBlit(wxCoord xdest, wxCoord ydest,
+                         wxCoord dstWidth, wxCoord dstHeight,
+                         wxDC *source,
+                         wxCoord xsrc, wxCoord ysrc,
+                         wxCoord srcWidth, wxCoord srcHeight,
+                         int logical_func = wxCOPY, bool useMask = false,
+                         wxCoord xsrcMask = wxDefaultCoord, wxCoord ysrcMask = wxDefaultCoord);
+{
+    wxCHECK_MSG(Ok(), false, wxT("wxDC::DoStretchBlit - invalid DC"));
+    wxCHECK_MSG(source->Ok(), false, wxT("wxDC::DoStretchBlit - invalid source DC"));
 
     if ( logical_func == wxNO_OP )
         return true ;
@@ -1198,12 +1212,12 @@ bool wxDC::DoBlit(wxCoord xdest, wxCoord ydest, wxCoord width, wxCoord height,
     Rect srcrect , dstrect ;
     srcrect.top = source->YLOG2DEVMAC(ysrc) ;
     srcrect.left = source->XLOG2DEVMAC(xsrc)  ;
-    srcrect.right = source->XLOG2DEVMAC(xsrc + width ) ;
-    srcrect.bottom = source->YLOG2DEVMAC(ysrc + height) ;
+    srcrect.right = source->XLOG2DEVMAC(xsrc + srcWidth ) ;
+    srcrect.bottom = source->YLOG2DEVMAC(ysrc + srcHeight) ;
     dstrect.top = YLOG2DEVMAC(ydest) ;
     dstrect.left = XLOG2DEVMAC(xdest) ;
-    dstrect.bottom = YLOG2DEVMAC(ydest + height )  ;
-    dstrect.right = XLOG2DEVMAC(xdest + width ) ;
+    dstrect.bottom = YLOG2DEVMAC(ydest + dstHeight )  ;
+    dstrect.right = XLOG2DEVMAC(xdest + dstWidth ) ;
     short mode = kUnsupportedMode ;
     bool invertDestinationFirst = false ;
 
diff --git a/src/mac/carbon/dccg.cpp b/src/mac/carbon/dccg.cpp
index 4cd27e7247..abd909dede 100755
--- a/src/mac/carbon/dccg.cpp
+++ b/src/mac/carbon/dccg.cpp
@@ -2021,8 +2021,22 @@ bool wxDC::DoBlit(
     wxDC *source, wxCoord xsrc, wxCoord ysrc, int logical_func , bool useMask,
     wxCoord xsrcMask, wxCoord ysrcMask )
 {
-    wxCHECK_MSG( Ok(), false, wxT("wxDC(cg)::DoBlit - invalid DC") );
-    wxCHECK_MSG( source->Ok(), false, wxT("wxDC(cg)::DoBlit - invalid source DC") );
+    return DoStretchBlit( xdest, ydest, width, height,
+                           source, xsrc, ysrc, width, height, 
+                           logical_func, useMask,
+                           xsrcMask, ysrcMask );
+}
+
+bool wxDC::DoStretchBlit(wxCoord xdest, wxCoord ydest,
+                         wxCoord dstWidth, wxCoord dstHeight,
+                         wxDC *source,
+                         wxCoord xsrc, wxCoord ysrc,
+                         wxCoord srcWidth, wxCoord srcHeight,
+                         int logical_func = wxCOPY, bool useMask = false,
+                         wxCoord xsrcMask = wxDefaultCoord, wxCoord ysrcMask = wxDefaultCoord);
+{
+    wxCHECK_MSG( Ok(), false, wxT("wxDC(cg)::DoStretchBlit - invalid DC") );
+    wxCHECK_MSG( source->Ok(), false, wxT("wxDC(cg)::DoStretchBlit - invalid source DC") );
 
     if ( logical_func == wxNO_OP )
         return true ;
@@ -2035,13 +2049,13 @@ bool wxDC::DoBlit(
 
     wxCoord yysrc = source->YLOG2DEVMAC(ysrc) ;
     wxCoord xxsrc = source->XLOG2DEVMAC(xsrc) ;
-    wxCoord wwsrc = source->XLOG2DEVREL(width) ;
-    wxCoord hhsrc = source->YLOG2DEVREL(height) ;
+    wxCoord wwsrc = source->XLOG2DEVREL(srcWidth) ;
+    wxCoord hhsrc = source->YLOG2DEVREL(srcHeight) ;
 
     wxCoord yydest = YLOG2DEVMAC(ydest) ;
     wxCoord xxdest = XLOG2DEVMAC(xdest) ;
-    wxCoord wwdest = XLOG2DEVREL(width) ;
-    wxCoord hhdest = YLOG2DEVREL(height) ;
+    wxCoord wwdest = XLOG2DEVREL(dstWidth) ;
+    wxCoord hhdest = YLOG2DEVREL(dstHeight) ;
 
     wxMemoryDC* memdc = dynamic_cast<wxMemoryDC*>(source) ;
     if ( memdc && logical_func == wxCOPY )
diff --git a/src/msw/dc.cpp b/src/msw/dc.cpp
index dd4750f6a0..344d9105c3 100644
--- a/src/msw/dc.cpp
+++ b/src/msw/dc.cpp
@@ -130,16 +130,21 @@ static inline double DegToRad(double deg) { return (deg * M_PI) / 180.0; }
 // return true if we could draw the bitmap in one way or the other, false
 // otherwise
 static bool AlphaBlt(HDC hdcDst,
-                     int x, int y, int w, int h,
-                     int srcX, int srcY, HDC hdcSrc,
-                     const wxBitmap& bmpSrc);
+                     int x, int y, int dstWidth, int dstHeight,
+                     int srcX, int srcY, 
+                     int srcWidth, int srcHeight,
+                     HDC hdcSrc,
+                     const wxBitmap& bmp);
 
 #ifdef wxHAVE_RAW_BITMAP
 
 // our (limited) AlphaBlend() replacement for Windows versions not providing it
 static void
-wxAlphaBlend(HDC hdcDst, int x, int y, int w, int h,
-             int srcX, int srcY, const wxBitmap& bmp);
+wxAlphaBlend(HDC hdcDst, int xDst, int yDst,
+             int dstWidth, int dstHeight,
+             int srcX, int srcY, 
+             int srcWidth, int srcHeight,
+             const wxBitmap& bmpSrc);
 
 #endif // wxHAVE_RAW_BITMAP
 
@@ -1183,7 +1188,7 @@ void wxDC::DoDrawBitmap( const wxBitmap &bmp, wxCoord x, wxCoord y, bool useMask
         MemoryHDC hdcMem;
         SelectInHDC select(hdcMem, GetHbitmapOf(bmp));
 
-        if ( AlphaBlt(GetHdc(), x, y, width, height, 0, 0, hdcMem, bmp) )
+        if ( AlphaBlt(GetHdc(), x, y, width, height, 0, 0, width, height, hdcMem, bmp) )
             return;
     }
 
@@ -2046,12 +2051,23 @@ wxCoord wxDCBase::LogicalToDeviceYRel(wxCoord y) const
 // ---------------------------------------------------------------------------
 // bit blit
 // ---------------------------------------------------------------------------
-
-bool wxDC::DoBlit(wxCoord xdest, wxCoord ydest,
-                  wxCoord width, wxCoord height,
-                  wxDC *source, wxCoord xsrc, wxCoord ysrc,
+bool wxDC::DoBlit(wxCoord dstX, wxCoord dstY,
+                  wxCoord dstWidth, wxCoord dstHeight,
+                  wxDC *source,
+                  wxCoord srcX, wxCoord srcY,
                   int rop, bool useMask,
-                  wxCoord xsrcMask, wxCoord ysrcMask)
+                  wxCoord srcMaskX, wxCoord srcMaskY)
+{
+    return DoStretchBlit(dstX, dstY, dstWidth, dstHeight, source, srcX, srcY, dstWidth, dstHeight, rop, useMask, srcMaskX, srcMaskY);
+}
+
+bool wxDC::DoStretchBlit(wxCoord xdest, wxCoord ydest,
+                         wxCoord dstWidth, wxCoord dstHeight,
+                         wxDC *source,
+                         wxCoord xsrc, wxCoord ysrc,
+                         wxCoord srcWidth, wxCoord srcHeight,
+                         int rop, bool useMask,
+                         wxCoord xsrcMask, wxCoord ysrcMask)
 {
     wxCHECK_MSG( source, false, _T("wxDC::Blit(): NULL wxDC pointer") );
 
@@ -2063,8 +2079,8 @@ bool wxDC::DoBlit(wxCoord xdest, wxCoord ydest,
     if ( bmpSrc.Ok() && (bmpSrc.HasAlpha() ||
             (m_selectedBitmap.Ok() && m_selectedBitmap.HasAlpha())) )
     {
-        if ( AlphaBlt(GetHdc(), xdest, ydest, width, height,
-                      xsrc, ysrc, GetHdcOf(*source), bmpSrc) )
+        if ( AlphaBlt(GetHdc(), xdest, ydest, dstWidth, dstHeight,
+                      xsrc, ysrc, srcWidth, srcHeight, GetHdcOf(*source), bmpSrc) )
             return true;
     }
 
@@ -2138,16 +2154,19 @@ bool wxDC::DoBlit(wxCoord xdest, wxCoord ydest,
         if (wxSystemOptions::GetOptionInt(wxT("no-maskblt")) == 0)
 #endif
         {
-           success = ::MaskBlt
-                       (
+            if ( dstWidth == srcWidth && dstHeight == srcHeight )
+            {
+                success = ::MaskBlt
+                            (
                             GetHdc(),
-                            xdest, ydest, width, height,
+                            xdest, ydest, dstWidth, dstHeight,
                             GetHdcOf(*source),
                             xsrc, ysrc,
                             (HBITMAP)mask->GetMaskBitmap(),
                             xsrcMask, ysrcMask,
                             MAKEROP4(dwRop, DSTCOPY)
-                        ) != 0;
+                            ) != 0;
+            }
         }
 
         if ( !success )
@@ -2167,55 +2186,59 @@ bool wxDC::DoBlit(wxCoord xdest, wxCoord ydest,
             dc_buffer = (HDC) dcCacheEntry2->m_dc;
 
             wxDCCacheEntry* bitmapCacheEntry = FindBitmapInCache(GetHDC(),
-                width, height);
+                dstWidth, dstHeight);
 
             buffer_bmap = (HBITMAP) bitmapCacheEntry->m_bitmap;
 #else // !wxUSE_DC_CACHEING
             // create a temp buffer bitmap and DCs to access it and the mask
             dc_mask = ::CreateCompatibleDC(GetHdcOf(*source));
             dc_buffer = ::CreateCompatibleDC(GetHdc());
-            buffer_bmap = ::CreateCompatibleBitmap(GetHdc(), width, height);
+            buffer_bmap = ::CreateCompatibleBitmap(GetHdc(), dstWidth, dstHeight);
 #endif // wxUSE_DC_CACHEING/!wxUSE_DC_CACHEING
             HGDIOBJ hOldMaskBitmap = ::SelectObject(dc_mask, (HBITMAP) mask->GetMaskBitmap());
             HGDIOBJ hOldBufferBitmap = ::SelectObject(dc_buffer, buffer_bmap);
 
             // copy dest to buffer
-            if ( !::BitBlt(dc_buffer, 0, 0, (int)width, (int)height,
+            if ( !::BitBlt(dc_buffer, 0, 0, (int)dstWidth, (int)dstHeight,
                            GetHdc(), xdest, ydest, SRCCOPY) )
             {
                 wxLogLastError(wxT("BitBlt"));
             }
 
+#ifndef __WXWINCE__
+            StretchBltModeChanger changeMode(dc_buffer, COLORONCOLOR);
+#endif
+
             // copy src to buffer using selected raster op
-            if ( !::BitBlt(dc_buffer, 0, 0, (int)width, (int)height,
-                           GetHdcOf(*source), xsrc, ysrc, dwRop) )
+            if ( !::StretchBlt(dc_buffer, 0, 0, (int)dstWidth, (int)dstHeight,
+                           GetHdcOf(*source), xsrc, ysrc, srcWidth, srcHeight, dwRop) )
             {
-                wxLogLastError(wxT("BitBlt"));
+                wxLogLastError(wxT("StretchBlt"));
             }
 
             // set masked area in buffer to BLACK (pixel value 0)
             COLORREF prevBkCol = ::SetBkColor(GetHdc(), RGB(255, 255, 255));
             COLORREF prevCol = ::SetTextColor(GetHdc(), RGB(0, 0, 0));
-            if ( !::BitBlt(dc_buffer, 0, 0, (int)width, (int)height,
-                           dc_mask, xsrcMask, ysrcMask, SRCAND) )
+            if ( !::StretchBlt(dc_buffer, 0, 0, (int)dstWidth, (int)dstHeight,
+                           dc_mask, xsrcMask, ysrcMask, srcWidth, srcHeight, SRCAND) )
             {
-                wxLogLastError(wxT("BitBlt"));
+                wxLogLastError(wxT("StretchBlt"));
             }
 
             // set unmasked area in dest to BLACK
             ::SetBkColor(GetHdc(), RGB(0, 0, 0));
             ::SetTextColor(GetHdc(), RGB(255, 255, 255));
-            if ( !::BitBlt(GetHdc(), xdest, ydest, (int)width, (int)height,
-                           dc_mask, xsrcMask, ysrcMask, SRCAND) )
+            if ( !::StretchBlt(GetHdc(), xdest, ydest, (int)dstWidth, (int)dstHeight,
+                           dc_mask, xsrcMask, ysrcMask, srcWidth, srcHeight, SRCAND) )
             {
-                wxLogLastError(wxT("BitBlt"));
+                wxLogLastError(wxT("StretchBlt"));
             }
             ::SetBkColor(GetHdc(), prevBkCol);   // restore colours to original values
             ::SetTextColor(GetHdc(), prevCol);
 
             // OR buffer to dest
             success = ::BitBlt(GetHdc(), xdest, ydest,
-                               (int)width, (int)height,
+                               (int)dstWidth, (int)dstHeight,
                                dc_buffer, 0, 0, SRCPAINT) != 0;
             if ( !success )
             {
@@ -2260,14 +2283,14 @@ bool wxDC::DoBlit(wxCoord xdest, wxCoord ydest,
                 if ( hDIB > 0 )
                 {
                     // reflect ysrc
-                    ysrc = hDIB - (ysrc + height);
+                    ysrc = hDIB - (ysrc + dstHeight);
                 }
 
                 if ( ::StretchDIBits(GetHdc(),
                                      xdest, ydest,
-                                     width, height,
+                                     dstWidth, dstHeight,
                                      xsrc, ysrc,
-                                     width, height,
+                                     srcWidth, srcHeight,
                                      ds.dsBm.bmBits,
                                      (LPBITMAPINFO)&ds.dsBmih,
                                      DIB_RGB_COLORS,
@@ -2298,9 +2321,9 @@ bool wxDC::DoBlit(wxCoord xdest, wxCoord ydest,
             if ( !::StretchBlt
                     (
                         GetHdc(),
-                        xdest, ydest, width, height,
+                        xdest, ydest, dstWidth, dstHeight,
                         GetHdcOf(*source),
-                        xsrc, ysrc, width, height,
+                        xsrc, ysrc, srcWidth, srcHeight,
                         dwRop
                     ) )
             {
@@ -2318,7 +2341,7 @@ bool wxDC::DoBlit(wxCoord xdest, wxCoord ydest,
                     (
                         GetHdc(),
                         xdest, ydest,
-                        (int)width, (int)height,
+                        (int)dstWidth, (int)dstHeight,
                         GetHdcOf(*source),
                         xsrc, ysrc,
                         dwRop
@@ -2540,8 +2563,10 @@ IMPLEMENT_DYNAMIC_CLASS(wxDCModule, wxModule)
 // ----------------------------------------------------------------------------
 
 static bool AlphaBlt(HDC hdcDst,
-                     int x, int y, int width, int height,
-                     int srcX, int srcY, HDC hdcSrc,
+                     int x, int y, int dstWidth, int dstHeight,
+                     int srcX, int srcY, 
+                     int srcWidth, int srcHeight,
+                     HDC hdcSrc,
                      const wxBitmap& bmp)
 {
     wxASSERT_MSG( bmp.Ok() && bmp.HasAlpha(), _T("AlphaBlt(): invalid bitmap") );
@@ -2564,8 +2589,8 @@ static bool AlphaBlt(HDC hdcDst,
         bf.SourceConstantAlpha = 0xff;
         bf.AlphaFormat = AC_SRC_ALPHA;
 
-        if ( pfnAlphaBlend(hdcDst, x, y, width, height,
-                           hdcSrc, srcX, srcY, width, height,
+        if ( pfnAlphaBlend(hdcDst, x, y, dstWidth, dstHeight,
+                           hdcSrc, srcX, srcY, srcWidth, srcHeight,
                            bf) )
         {
             // skip wxAlphaBlend() call below
@@ -2581,7 +2606,7 @@ static bool AlphaBlt(HDC hdcDst,
     // AlphaBlend() unavailable of failed: use our own (probably much slower)
     // implementation
 #ifdef wxHAVE_RAW_BITMAP
-    wxAlphaBlend(hdcDst, x, y, width, height, srcX, srcY, bmp);
+    wxAlphaBlend(hdcDst, x, y, dstWidth, dstHeight, srcX, srcY, srcWidth, srcHeight, bmp);
 
     return true;
 #else // !wxHAVE_RAW_BITMAP
@@ -2598,15 +2623,17 @@ static bool AlphaBlt(HDC hdcDst,
 
 static void
 wxAlphaBlend(HDC hdcDst, int xDst, int yDst,
-             int w, int h,
-             int srcX, int srcY, const wxBitmap& bmpSrc)
+             int dstWidth, int dstHeight,
+             int srcX, int srcY, 
+             int srcWidth, int srcHeight,
+             const wxBitmap& bmpSrc)
 {
     // get the destination DC pixels
-    wxBitmap bmpDst(w, h, 32 /* force creating RGBA DIB */);
+    wxBitmap bmpDst(dstWidth, dstHeight, 32 /* force creating RGBA DIB */);
     MemoryHDC hdcMem;
     SelectInHDC select(hdcMem, GetHbitmapOf(bmpDst));
 
-    if ( !::BitBlt(hdcMem, 0, 0, w, h, hdcDst, xDst, yDst, SRCCOPY) )
+    if ( !::BitBlt(hdcMem, 0, 0, dstWidth, dstHeight, hdcDst, xDst, yDst, SRCCOPY) )
     {
         wxLogLastError(_T("BitBlt"));
     }
@@ -2621,15 +2648,17 @@ wxAlphaBlend(HDC hdcDst, int xDst, int yDst,
     wxAlphaPixelData::Iterator pDst(dataDst),
                                pSrc(dataSrc);
 
-    pSrc.Offset(dataSrc, srcX, srcY);
 
-    for ( int y = 0; y < h; y++ )
+    for ( int y = 0; y < dstHeight; y++ )
     {
-        wxAlphaPixelData::Iterator pDstRowStart = pDst,
-                                   pSrcRowStart = pSrc;
+        wxAlphaPixelData::Iterator pDstRowStart = pDst;
 
-        for ( int x = 0; x < w; x++ )
+        for ( int x = 0; x < dstWidth; x++ )
         {
+            // source is point sampled, Alpha StretchBlit is ugly on Win95
+            // (but does not impact performance)
+            pSrc.MoveTo(dataSrc, srcX + (srcWidth*x/dstWidth), srcY + (srcHeight*y/dstHeight));
+
             // note that source bitmap uses premultiplied alpha (as required by
             // the real AlphaBlend)
             const unsigned beta = 255 - pSrc.Alpha();
@@ -2639,17 +2668,14 @@ wxAlphaBlend(HDC hdcDst, int xDst, int yDst,
             pDst.Green() = pSrc.Green() + (beta * pDst.Green() + 127) / 255;
 
             ++pDst;
-            ++pSrc;
         }
 
         pDst = pDstRowStart;
-        pSrc = pSrcRowStart;
         pDst.OffsetY(dataDst, 1);
-        pSrc.OffsetY(dataSrc, 1);
     }
 
     // and finally blit them back to the destination DC
-    if ( !::BitBlt(hdcDst, xDst, yDst, w, h, hdcMem, 0, 0, SRCCOPY) )
+    if ( !::BitBlt(hdcDst, xDst, yDst, dstWidth, dstHeight, hdcMem, 0, 0, SRCCOPY) )
     {
         wxLogLastError(_T("BitBlt"));
     }
-- 
2.50.0

