mORMot Open Source

Hi

This is a follow-up to a post in an Embarcadero forum.
First question:
is it possible to make a document that looks the
same on whatever print is printed?
Second question:
I draw text and images on a Tprintpox with a funccion
     dcrawcanvas(self.canvas);
Then, when the PDF option is selected, I do
  lPdf := TPdfDocumentGDI.Create;
  try
    lpdf.DefaultPageWidth:=printpox_width;
    lpdf.DefaultPageHeight:=printbox_height;
    lPage := lPDF.AddPage;
    lPdf.ScreenLogPixels:=scrresy;
    lPDF.VCLCanvas.font.name:='Arial';   
    drawcanvas(lPDF.VCLCanvas);
   etc.
When I view the saved PDF file with Acrobat, in 'actual size',
the document content (text and images) seem to be the same
(in mm) as the rendition on the screen,but the page (white space)
width is approx.10 MM while the width i passed (printbox-width) is
8 MM.
Moreover, if I print it on a Laserjet printer (600x600) the content is much smaller(about 4MM wide instead of the 8MM that the onscreen image
of the form and of the Acrobate document show).
Am I totally off track?
I appreciate any help.
Enrico