mORMot Open Source

Chaa

Member

Registered: 2011-03-26

Posts: 249

Several fixes in RenderMetaFile

Several fixes in RenderMetaFile:

1. Added fNewPath := False to TPdfCanvas.DrawXObjectEx. Without this code, lines after the image is not drawn correctly.

   procedure TPdfCanvas.DrawXObjectEx(X, Y, AWidth, AHeight: Single;
         ClipX, ClipY, ClipWidth, ClipHeight: Single; const AXObjectName: PDFString);
   begin
     DrawXObjectPrepare(AXObjectName);
     GSave;
     Rectangle(ClipX, ClipY, ClipWidth, ClipHeight);
     Clip;
     NewPath;
     fNewPath := False;
     ConcatToCTM(AWidth, 0, 0, AHeight, X, Y);
     ExecuteXObject(AXObjectName);
     GRestore;
   end;

2. Added EMR_TRANSPARENTBLT and setting "Color Key Masking" attribute for image. Perhaps it should be done more accurately. PDF spec is not clear about how to do this for 8-bit images.

3. Added hack to mirror image when WorldTransform.eM22 has negative value, i.e. "Vertical reflection component" in http://msdn.microsoft.com/en-us/library … s.85).aspx

   EMR_STRETCHDIBITS:
     with PEMRStretchDIBits(R)^ do // only handle RGB bitmaps (no palette)
       if (offBmiSrc<>0) and (offBitsSrc<>0) then begin
         if WorldTransform.eM22 < 0 then
           with PBitmapInfo(PtrUInt(R)+offBmiSrc)^ do
             bmiHeader.biHeight := -bmiHeader.biHeight;

   There also may be "Horizontal reflection component" in WorldTransform.eM11. Reflection can be done by changing sign of image width or height parameter in StretchDIBits call.

Source code and images.

ab

Administrator

From: France

Registered: 2010-06-21

Posts: 14,660

Website

Re: Several fixes in RenderMetaFile

I've added those enhancements.
See http://synopse.info/fossil/info/c1b5c0772a

Thanks!