IMPLEMENT_DYNAMIC_CLASS(wxMemoryDC,wxDC)
-wxMemoryDC::wxMemoryDC(void)
+void wxMemoryDC::Init()
{
m_cocoaNSImage = NULL;
m_ok = false;
wxMemoryDC::wxMemoryDC( wxDC *WXUNUSED(dc) )
{
- m_cocoaNSImage = NULL;
- m_ok = false;
+ Init();
}
wxMemoryDC::~wxMemoryDC(void)
// 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 wxMemoryDC::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,
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)
[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;
}