]> git.saurik.com Git - wxWidgets.git/blobdiff - src/cocoa/dcmemory.mm
ensure that the copies of the bitmap passed to wxMemoryDC ctor are not modified when...
[wxWidgets.git] / src / cocoa / dcmemory.mm
index f3f2d3e2d0d23829b8556384762023d9d7282de7..0eb5905b14faca218e4678017dbb921d8c390064 100644 (file)
@@ -1,20 +1,21 @@
 /////////////////////////////////////////////////////////////////////////////
 // Name:        src/cocoa/dcmemory.mm
-// Purpose:     wxMemoryDC class
+// Purpose:     wxMemoryDCImpl class
 // Author:      David Elliott
 // Modified by:
 // Created:     2003/03/16
 // RCS-ID:      $Id$
 // Copyright:   (c) 2002 David Elliott
-// Licence:    wxWidgets licence
+// Licence:     wxWidgets licence
 /////////////////////////////////////////////////////////////////////////////
 
 #include "wx/wxprec.h"
+
 #ifndef WX_PRECOMP
     #include "wx/log.h"
-    #include "wx/dcmemory.h"
 #endif //WX_PRECOMP
 
+#include "wx/cocoa/dcmemory.h"
 #include "wx/cocoa/autorelease.h"
 
 #import <AppKit/NSImage.h>
 #import <AppKit/NSBezierPath.h>
 
 //-----------------------------------------------------------------------------
-// wxMemoryDC
+// wxMemoryDCImpl
 //-----------------------------------------------------------------------------
 
-IMPLEMENT_DYNAMIC_CLASS(wxMemoryDC,wxDC)
+IMPLEMENT_ABSTRACT_CLASS(wxMemoryDCImpl,wxCocoaDCImpl)
 
-wxMemoryDC::wxMemoryDC(void)
+void wxMemoryDCImpl::Init()
 {
     m_cocoaNSImage = NULL;
     m_ok = false;
 }
 
-wxMemoryDC::wxMemoryDC( wxDC *WXUNUSED(dc) )
+wxMemoryDCImpl::wxMemoryDCImpl(wxMemoryDC *owner, wxDC *WXUNUSED(dc))
+:   wxCocoaDCImpl(owner)
 {
-    m_cocoaNSImage = NULL;
-    m_ok = false;
+    Init();
 }
 
-wxMemoryDC::~wxMemoryDC(void)
+wxMemoryDCImpl::~wxMemoryDCImpl(void)
 {
     CocoaUnwindStackAndLoseFocus();
     [m_cocoaNSImage release];
 }
 
-bool wxMemoryDC::CocoaLockFocus()
+bool wxMemoryDCImpl::CocoaLockFocus()
 {
     if(m_cocoaNSImage)
     {
         [m_cocoaNSImage lockFocus];
         sm_cocoaDCStack.Insert(this);
-        m_cocoaWxToBoundsTransform = CocoaGetWxToBoundsTransform([m_cocoaNSImage isFlipped], [m_cocoaNSImage size].height);
+        NSAffineTransform *newTransform = CocoaGetWxToBoundsTransform([m_cocoaNSImage isFlipped], [m_cocoaNSImage size].height);
+        [newTransform retain];
+        [m_cocoaWxToBoundsTransform release];
+        m_cocoaWxToBoundsTransform = newTransform;
         CocoaApplyTransformations();
         return true;
     }
     return false;
 }
 
-bool wxMemoryDC::CocoaUnlockFocus()
+bool wxMemoryDCImpl::CocoaUnlockFocus()
 {
     [m_cocoaNSImage unlockFocus];
     return true;
@@ -68,13 +72,19 @@ bool wxMemoryDC::CocoaUnlockFocus()
 
 // NOTE: The AppKit is unable to draw onto an NSBitmapImageRep so we must
 // instead copy the data to an offscreen window, then copy it back
-void wxMemoryDC::SelectObject( const wxBitmap& bitmap )
+void wxMemoryDCImpl::DoSelect( const wxBitmap& bitmap )
 {
     wxAutoNSAutoreleasePool pool;
     if(m_selectedBitmap.Ok())
     {
         CocoaTakeFocus();
         wxASSERT(m_cocoaNSImage);
+        // Replace the bitmap's native data with a newly created one based on the
+        // NSImage that has been (potentially) drawn upon.  Note that this may and
+        // probably will in many cases change the bitmap's format.
+        // There is nothing we can do about this using pure Cocoa code.  Even using
+        // CGBitmapContext is not an option because it only supports a limited
+        // number of bitmap formats.  Specifically, 24-bpp is not supported.
         m_selectedBitmap.SetNSBitmapImageRep(
             [[NSBitmapImageRep alloc]
                 initWithFocusedViewRect:NSMakeRect(0.0,0.0,
@@ -93,6 +103,16 @@ void wxMemoryDC::SelectObject( const wxBitmap& bitmap )
                     m_selectedBitmap.GetHeight())];
 
         // Now copy the data
+        // Pass false to GetNSImage so the mask is not applied as an alpha channel.
+        // Cocoa uses premultiplied alpha so applying the mask would cause all
+        // color information masked out to be turned black which is undesirable.
+        // FIXME: Currently, the mask will not be updated if any drawing occurs.
+        // My only suggestion is for wxCocoa users to eschew the mask in favor
+        // of an alpha channel or to recreate the mask after drawing.
+        // The only way to fix this is to draw twice, once as normal and again
+        // onto the mask to update it.  That would require overriding every
+        // single drawing primitive (e.g. DoDrawLine, DoDrawRectangle, etc.)
+        // and would be a major undertaking.
         NSImage *nsimage = [m_selectedBitmap.GetNSImage(false) retain];
         [m_cocoaNSImage lockFocus];
         [nsimage drawAtPoint: NSMakePoint(0,0)
@@ -100,12 +120,12 @@ void wxMemoryDC::SelectObject( const wxBitmap& bitmap )
             operation: NSCompositeCopy
             fraction: 1.0];
         [m_cocoaNSImage unlockFocus];
-        
+
         [nsimage release];
     }
 }
 
-void wxMemoryDC::DoGetSize( int *width, int *height ) const
+void wxMemoryDCImpl::DoGetSize( int *width, int *height ) const
 {
     if(width)
         *width = m_selectedBitmap.GetWidth();
@@ -113,7 +133,7 @@ void wxMemoryDC::DoGetSize( int *width, int *height ) const
         *height = m_selectedBitmap.GetHeight();
 }
 
-bool wxMemoryDC::CocoaDoBlitOnFocusedDC(wxCoord xdest, wxCoord ydest,
+bool wxMemoryDCImpl::CocoaDoBlitOnFocusedDC(wxCoord xdest, wxCoord ydest,
     wxCoord width, wxCoord height, wxCoord xsrc, wxCoord ysrc,
     int logicalFunc, bool useMask, wxCoord xsrcMask, wxCoord ysrcMask)
 {
@@ -139,32 +159,62 @@ bool wxMemoryDC::CocoaDoBlitOnFocusedDC(wxCoord xdest, wxCoord ydest,
     [transform concat];
     [flipTransform concat];
 
+    NSImage *sourceImage;
+    if(useMask)
+    {
+        sourceImage = [m_cocoaNSImage copy];
+        // Apply the mask to the copied image
+        NSBitmapImageRep *maskRep = m_selectedBitmap.GetMask()->GetNSBitmapImageRep();
+        NSImage *maskImage = [[NSImage alloc] initWithSize:[maskRep size]];
+        [maskImage addRepresentation:maskRep];
+        [sourceImage lockFocus];
+        [maskImage compositeToPoint:NSZeroPoint operation:NSCompositeDestinationIn];
+        [sourceImage unlockFocus];
+        [maskImage release];
+    }
+    else
+    {   // retain the m_cocoaNSImage so it has the same ownership as the copy done in the other case.
+        sourceImage = [m_cocoaNSImage retain];
+    }
+    NSCompositingOperation drawingOp;
+    switch(logicalFunc)
+    {
+    case wxCOPY:
+        // Even if not using the mask, the image might have an alpha channel
+        // so always use NSCompositeSourceOver.  If the image is fully opaque
+        // it works out the same as NSCompositeCopy.
+        drawingOp = NSCompositeSourceOver;
+        break;
+    // FIXME: implement more raster ops
+    default:
+        wxLogDebug(wxT("wxCocoa does not support blitting with raster operation %d."), logicalFunc);
+        // Just use the default operation.
+        drawingOp = NSCompositeCopy;
+    }
+
     wxLogTrace(wxTRACE_COCOA,wxT("[m_cocoaNSImage isFlipped]=%d"), [m_cocoaNSImage isFlipped]);
-    [m_cocoaNSImage drawAtPoint: NSMakePoint(0,0)
+    [sourceImage drawAtPoint: NSMakePoint(0,0)
         fromRect: NSMakeRect(xsrc,
             m_selectedBitmap.GetHeight()-height-ysrc,
             width, height)
-        operation: NSCompositeCopy // FIXME: raster ops
+        operation: drawingOp
         fraction: 1.0];
-        
+
+    [sourceImage release]; // It was either retained, copied, or allocated.
     [context restoreGraphicsState];
     return false;
 }
 
-void wxMemoryDC::Clear()
+bool wxMemoryDCImpl::CocoaGetBounds(void *rectData)
 {
-    if(!CocoaTakeFocus()) return;
-
-    NSGraphicsContext *context = [NSGraphicsContext currentContext];
-    [context saveGraphicsState];
-
-    [m_backgroundBrush.GetNSColor() set];
-    NSRect rect;
-    rect.origin.x = 0;
-    rect.origin.y = 0;
-    rect.size = [m_cocoaNSImage size];
-    [NSBezierPath fillRect:rect];
-
-    [context restoreGraphicsState];
+    if(!rectData)
+        return false;
+    if(!m_cocoaNSImage)
+        return false;
+    NSRect *pRect = (NSRect*)rectData;
+    pRect->origin.x = 0.0;
+    pRect->origin.y = 0.0;
+    pRect->size = [m_cocoaNSImage size];
+    return true;
 }