How do I make a bitmap version of a WMF file that is loaded into a TImage.Picture and move that to a TSpeedButton.Glyph

Thanks David, for suggesting that I draw the background. This works.

Note that in production I would change the code below to use Vcl.GraphUtils helper called ScaleImage as the results are much prettier. See the second code sample.

// Quick and Dirty : No sub-pixel anti-aliasing.
// Also does not modifies Source, so set Source's size before you 
// call this. 
procedure CopyBitmap(  Source:TImage;  DestSpeedButton:TSpeedButton );
var
   bmp: TBitmap;
begin
   bmp:=TBitmap.Create;
   try
     bmp.SetSize( Source.Width, Source.Height);
     bmp.Canvas.Pen.Style := psClear;
     bmp.Canvas.Brush.Style := bsSolid;
     bmp.Canvas.Brush.Color := clFuchsia;
     bmp.Canvas.Rectangle(0,0, Source.Width+1,Source.Height+1 );
     bmp.Canvas.Draw(0,0, Source.Picture.Graphic );
     bmp.TransparentColor := clFuchsia;
     DestSpeedButton.Glyph:=bmp;
   finally
     bmp.Free;
   end;
end;

Alternative that uses more memory, and is using the TPicture type instead of TImage because in real use I don't even have a TImage just a TPicture, also this looks nicer. Note that it is written around some custom control of my own design (or yours) that has some property type TBitmap. You have to substitute your own controls, or change TMyControlWithAGlyph to TSpeedButton if that's what you want to do:

// A Bit Better Looking. Uses Vcl.GraphUtils function ScaleImage
procedure CopyBitmap(  Source:TPicture;
                       Dest:TMyControlWithAGlyph;
                       DestType:TCopyDestTypeEnum;
                       AWidth,AHeight:Integer;
                       DoInvert:Boolean;
                       TransparentColor:TColor=clFuchsia );
var
   bmp,bmpFullSize: TBitmap;
   ARect:TRect;
   ScaleAmount:Double;
begin
   if not Assigned(Source) then
      exit;
   if not Assigned(Dest) then
      exit;

   if not Assigned(Source.Graphic) then
      exit;


   bmp:=TBitmap.Create;
   bmpFullSize := TBitmap.Create;
   try
     bmpFullSize.SetSize(  Source.Width, Source.Height );
     bmpFullSize.PixelFormat := pf24bit;
     bmpFullSize.Canvas.Pen.Style := psClear;
     bmpFullSize.Canvas.Brush.Style := bsSolid;
     bmpFullSize.Canvas.Brush.Color := TransparentColor;
     bmpFullSize.Canvas.Rectangle(0,0, Source.Width+1,Source.Height+1 );
     bmpFullSize.Canvas.Draw(0,0, Source.Graphic );


     bmp.SetSize( AWidth, AHeight);
     bmp.PixelFormat := pf24bit;

     // Vcl.GraphiUtil version needs a floating point scale.
     ScaleAmount := AWidth / Source.Width;
     ScaleImage(bmpFullSize,bmp,ScaleAmount );

     // This lets me have a white icon and turn it black if I want to
     // or vice versa
     if DoInvert then
       InvertBitmap(bmp); 

     if DestType=DestLargeGlyph then
     begin
          Dest.LargeGlyph := bmp;
     end
     else
     begin
          Dest.Glyph:=bmp;
     end;
   finally
     bmp.Free;
     bmpFullSize.Free;
   end;
end;

The above code also calls this little helper:

function InvertBitmap(ABitmap: TBitmap): TBitmap;
var
   x, y: Integer;
   ByteArray: PByteArray;
begin
   ABitmap.PixelFormat := pf24Bit;
   for y := 0 to ABitmap.Height - 1 do
   begin
      ByteArray := ABitmap.ScanLine[y];
      for x := 0 to ABitmap.Width * 3 - 1 do
      begin
         ByteArray[x] := 255 - ByteArray[x];
      end;
   end;
   Result := ABitmap;
end;