Lazarus: Aspect Ratio is off

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   I have successfully installed QuickPDF 10.13 Active X in Lazarus 1.8.4.  I am able to display .Pdf documents.  Everything I need to do is "mostly" working, however I have an annoying problem.  The displayed aspect ratio is not correct.  The displayed image of the Pdf page is always a little fuzzy, unlike when the same .Pdf file is displayed in Adobe or Nuance, which is always clear.  
Also, when I display in zooms above 100%, the right edge is cut off.  As I zoom higher and higher (like 400% for example, more and more of the right edge is cut off).  Unlike in the Delphi version, the ActiveX version of QuickPDF does not have the very convenient and simple "LoadFromStream" which takes care of all the aspect ratio, zoom, and rotation etc. In the ActiveX version I have to do all this manually.  Here is the code I am using.  Can some generous person correct it so I can get nice clear .Pdf renderings, with the full image showing regardless of rotation or zoom?
<CODE>

function RenderPDFPageAX(const fnm: String; const img: TImage; const pg: Integer; var pc: Integer; const zm: Integer; var err_msg: String): Boolean;
var
  vch: Variant;  // Variant containing the Canvas Handle
  bmp: TBitmap;
  dpi, pg_rt, zdvi: Integer;   zdvd: Double;
  wdtd, hgtd, wdtn, hgtn, wdts, hgts: Double;
  wdti, hgti: Integer;
  rnd_md: TFPURoundingMode;
  sbx: TScrollBox;
  obj: TObject;
  tmp_fnm: String;
begin
  Result := True;
  err_msg := '';
  sbx := nil;

  ReleasePdfImg(img);

  obj := img.Parent;
  if not Assigned(obj) then
    Exit;
  if (obj is TScrollBox) then
    sbx := (obj as TScrollBox);
  if not Assigned(sbx) then
    Exit;

  sbx.HorzScrollBar.Position := 0;
  sbx.VertScrollBar.Position := 0;

  img.AutoSize := True;
  img.Left := 0;
  img.Top := 0;
  img.Visible := True;

  bmp := nil;
  try
    if Assigned(GlobalVars.QwkPdf.axl) then
      begin
        inc(GlobalVars.RenderID);
        tmp_fnm := GlobalVars.AppProps.pdf_tmp_fdr + IntToStr(GlobalVars.RenderID) + '.dat';
        GlobalVars.QwkPdf.axl.OleServer.SetTempFile(tmp_fnm);

        Result := (GlobalVars.QwkPdf.axl.OleServer.LoadFromFile(fnm, '') = 1);
        if Result then
          begin
            pc := GlobalVars.QwkPdf.axl.OleServer.PageCount;
            GlobalVars.QwkPdf.axl.OleServer.SelectPage(pg);
            pg_rt := GlobalVars.QwkPdf.axl.OleServer.PageRotation;

            // Page Points
            wdtd := GlobalVars.QwkPdf.axl.OleServer.PageWidth;
            hgtd := GlobalVars.QwkPdf.axl.OleServer.PageHeight;

            // Page Points to Inches
            wdtn := wdtd / 72;
            hgtn := hgtd / 72;

            // Inches to Screen pixels
            wdts := wdtn * GlobalVars.QwkPdf.sppi;
            hgts := hgtn * GlobalVars.QwkPdf.sppi;

            rnd_md := Math.GetRoundMode;
            Math.SetRoundMode(rmUp);
            wdti := Round(wdts);
            hgti := Round(hgts);
            Math.SetRoundMode(rnd_md);

            bmp := TBitmap.Create;
            bmp.Canvas.Brush.Color := clWhite;

            if (pg_rt = 0) or (pg_rt = 180) then
              begin
                bmp.Width := wdti;
                bmp.Height := hgti;
              end
            else
              begin
                bmp.Width := hgti;
                bmp.Height := wdti;
              end;

            // Adjust for Zoom
            dpi := (zm * GlobalVars.QwkPdf.sppi) div 100;
            if not (zm = 100) then
              begin
                if (zm > 100) then
                  begin
                    zdvi := (zm div 100);
                    bmp.Width := bmp.Width * zdvi;
                    bmp.Height := bmp.Height * zdvi;
                  end;
                if (zm < 100) then
                  begin
                    zdvd := (zm / 100);
                    bmp.Width := Trunc(bmp.Width * zdvd);
                    bmp.Height := Trunc(bmp.Height * zdvd);
                  end;
              end;

            bmp.Canvas.FillRect(Rect(0, 0, bmp.Width, bmp.Height));
            img.Picture.Assign(bmp);
            vch := bmp.Canvas.Handle;
          end
        else
          begin
            err_msg := 'Unable to load PDF Viewer from file: ' + fnm + #13 + 'ErrorCode: ' + IntToStr(GlobalVars.QwkPdf.axl.OleServer.LastErrorCode);
            Exit;
          end;

        Result := (GlobalVars.QwkPdf.axl.OleServer.RenderPageToDC(dpi, pg, vch) = 1);
        if not Result then
          begin
            err_msg := 'Unable to render image from QuickPDF ActiveX' + #13 + GlobalVars.QwkPdf.axl.OleServer.LastRenderError;
            Exit;
          end;
      end;
  finally
    bmp.Free;
  end;
end;

</CODE>

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RedOctober2018 Members Profile Find Members Posts Team Player Joined: 22 Jun 18 Location: West Status: Offline Points: 25	Post Options Post Reply Quote RedOctober2018 Report Post Thanks(0) Quote Reply Topic: Lazarus: Aspect Ratio is off Posted: 22 Jun 19 at 4:43PM
	I have successfully installed QuickPDF 10.13 Active X in Lazarus 1.8.4. I am able to display .Pdf documents. Everything I need to do is "mostly" working, however I have an annoying problem. The displayed aspect ratio is not correct. The displayed image of the Pdf page is always a little fuzzy, unlike when the same .Pdf file is displayed in Adobe or Nuance, which is always clear. Also, when I display in zooms above 100%, the right edge is cut off. As I zoom higher and higher (like 400% for example, more and more of the right edge is cut off). Unlike in the Delphi version, the ActiveX version of QuickPDF does not have the very convenient and simple "LoadFromStream" which takes care of all the aspect ratio, zoom, and rotation etc. In the ActiveX version I have to do all this manually. Here is the code I am using. Can some generous person correct it so I can get nice clear .Pdf renderings, with the full image showing regardless of rotation or zoom? <CODE> function RenderPDFPageAX(const fnm: String; const img: TImage; const pg: Integer; var pc: Integer; const zm: Integer; var err_msg: String): Boolean; var vch: Variant; // Variant containing the Canvas Handle bmp: TBitmap; dpi, pg_rt, zdvi: Integer; zdvd: Double; wdtd, hgtd, wdtn, hgtn, wdts, hgts: Double; wdti, hgti: Integer; rnd_md: TFPURoundingMode; sbx: TScrollBox; obj: TObject; tmp_fnm: String; begin Result := True; err_msg := ''; sbx := nil; ReleasePdfImg(img); obj := img.Parent; if not Assigned(obj) then Exit; if (obj is TScrollBox) then sbx := (obj as TScrollBox); if not Assigned(sbx) then Exit; sbx.HorzScrollBar.Position := 0; sbx.VertScrollBar.Position := 0; img.AutoSize := True; img.Left := 0; img.Top := 0; img.Visible := True; bmp := nil; try if Assigned(GlobalVars.QwkPdf.axl) then begin inc(GlobalVars.RenderID); tmp_fnm := GlobalVars.AppProps.pdf_tmp_fdr + IntToStr(GlobalVars.RenderID) + '.dat'; GlobalVars.QwkPdf.axl.OleServer.SetTempFile(tmp_fnm); Result := (GlobalVars.QwkPdf.axl.OleServer.LoadFromFile(fnm, '') = 1); if Result then begin pc := GlobalVars.QwkPdf.axl.OleServer.PageCount; GlobalVars.QwkPdf.axl.OleServer.SelectPage(pg); pg_rt := GlobalVars.QwkPdf.axl.OleServer.PageRotation; // Page Points wdtd := GlobalVars.QwkPdf.axl.OleServer.PageWidth; hgtd := GlobalVars.QwkPdf.axl.OleServer.PageHeight; // Page Points to Inches wdtn := wdtd / 72; hgtn := hgtd / 72; // Inches to Screen pixels wdts := wdtn * GlobalVars.QwkPdf.sppi; hgts := hgtn * GlobalVars.QwkPdf.sppi; rnd_md := Math.GetRoundMode; Math.SetRoundMode(rmUp); wdti := Round(wdts); hgti := Round(hgts); Math.SetRoundMode(rnd_md); bmp := TBitmap.Create; bmp.Canvas.Brush.Color := clWhite; if (pg_rt = 0) or (pg_rt = 180) then begin bmp.Width := wdti; bmp.Height := hgti; end else begin bmp.Width := hgti; bmp.Height := wdti; end; // Adjust for Zoom dpi := (zm * GlobalVars.QwkPdf.sppi) div 100; if not (zm = 100) then begin if (zm > 100) then begin zdvi := (zm div 100); bmp.Width := bmp.Width * zdvi; bmp.Height := bmp.Height * zdvi; end; if (zm < 100) then begin zdvd := (zm / 100); bmp.Width := Trunc(bmp.Width * zdvd); bmp.Height := Trunc(bmp.Height * zdvd); end; end; bmp.Canvas.FillRect(Rect(0, 0, bmp.Width, bmp.Height)); img.Picture.Assign(bmp); vch := bmp.Canvas.Handle; end else begin err_msg := 'Unable to load PDF Viewer from file: ' + fnm + #13 + 'ErrorCode: ' + IntToStr(GlobalVars.QwkPdf.axl.OleServer.LastErrorCode); Exit; end; Result := (GlobalVars.QwkPdf.axl.OleServer.RenderPageToDC(dpi, pg, vch) = 1); if not Result then begin err_msg := 'Unable to render image from QuickPDF ActiveX' + #13 + GlobalVars.QwkPdf.axl.OleServer.LastRenderError; Exit; end; end; finally bmp.Free; end; end; </CODE>

RedOctober2018 Members Profile Find Members Posts Team Player Joined: 22 Jun 18 Location: West Status: Offline Points: 25	Post Options Post Reply Quote RedOctober2018 Report Post Thanks(0) Quote Reply Posted: 30 Jun 19 at 7:44PM
	For those who are interested, here is the corrected code. I set the color of the BitMap to blue, so you can tell if the document is contained within an exact same sized image as the BitMap, or if the BitMap is a tiny bit bigger. This code fixes the problem I had above, and appears to make an exact same sized BitMap (which is perfect) or one that is just a few pixels larger (which is ok). In any case, the document is no longer being cut off, and rotation works as well. <CODE> function RenderPDFPageAX(const fnm: String; const img: TImage; const pg: Integer; var pc: Integer; const zm: Integer; var err_msg: String): Boolean; var vch: Variant; // Variant containing the Canvas Handle bmp: TBitmap; dpi, pg_rt, zdvi: Integer; zdvd: Double; wdtd, hgtd, wdtn, hgtn, wdts, hgts: Double; wdti, hgti: Integer; rnd_md: TFPURoundingMode; sbx: TScrollBox; obj: TObject; tmp_fnm: String; begin Result := True; err_msg := ''; sbx := nil; ReleasePdfImg(img); obj := img.Parent; if not Assigned(obj) then Exit; if (obj is TScrollBox) then sbx := (obj as TScrollBox); if not Assigned(sbx) then Exit; sbx.HorzScrollBar.Position := 0; sbx.VertScrollBar.Position := 0; img.AutoSize := True; img.Left := 0; img.Top := 0; img.Visible := True; bmp := nil; try if Assigned(GlobalVars.QwkPdf.axl) then begin inc(GlobalVars.RenderID); tmp_fnm := GlobalVars.AppProps.pdf_tmp_fdr + IntToStr(GlobalVars.RenderID) + '.dat'; GlobalVars.QwkPdf.axl.OleServer.SetTempFile(tmp_fnm); Result := (GlobalVars.QwkPdf.axl.OleServer.LoadFromFile(fnm, '') = 1); if Result then begin with GlobalVars.QwkPdf.axl.OleServer do begin SetMeasurementUnits(2); // 2 = Inches. SetGDIPlusOptions(0, 1); SetGDIPlusOptions(1, 1); SetGDIPlusOptions(2, 1); SetGDIPlusOptions(3, 1); SetGDIPlusOptions(10, 2); SetGDIPlusOptions(11, 2); end; pc := GlobalVars.QwkPdf.axl.OleServer.PageCount; GlobalVars.QwkPdf.axl.OleServer.SelectPage(pg); pg_rt := GlobalVars.QwkPdf.axl.OleServer.PageRotation; // Page Size in inches wdtd := GlobalVars.QwkPdf.axl.OleServer.PageWidth; hgtd := GlobalVars.QwkPdf.axl.OleServer.PageHeight; bmp := TBitmap.Create; bmp.Canvas.Brush.Color := clBlue; //clWhite; // Inches to Screen pixels wdti := Trunc(wdtd * GlobalVars.QwkPdf.sppi); hgti := Trunc(hgtd * GlobalVars.QwkPdf.sppi); if (pg_rt = 0) or (pg_rt = 180) then begin bmp.Width := wdti; bmp.Height := hgti; end else begin bmp.Width := hgti; bmp.Height := wdti; end; // Adjust for Zoom zdvd := 1; if not (zm = 100) then begin if (zm > 100) then begin zdvd := (zm div 100); end; if (zm < 100) then begin zdvd := (zm / 100); end; end; wdti := Trunc(bmp.Width * zdvd); hgti := Trunc(bmp.Height * zdvd); bmp.Width := wdti; bmp.Height := hgti; bmp.Canvas.FillRect(Rect(0, 0, bmp.Width, bmp.Height)); img.Picture.Assign(bmp); vch := bmp.Canvas.Handle; end else begin err_msg := 'Unable to load PDF Viewer from file: ' + fnm + #13 + 'ErrorCode: ' + IntToStr(GlobalVars.QwkPdf.axl.OleServer.LastErrorCode); Exit; end; Result := (GlobalVars.QwkPdf.axl.OleServer.RenderPageToDC(Trunc(GlobalVars.QwkPdf.sppi * zdvd), pg, vch) = 1); if not Result then begin err_msg := 'Unable to render image from QuickPDF ActiveX' + #13 + GlobalVars.QwkPdf.axl.OleServer.LastRenderError; Exit; end; end; finally bmp.Free; end; end; </CODE> Edited by RedOctober2018 - 30 Jun 19 at 10:23PM

RedOctober2018 Members Profile Find Members Posts Team Player Joined: 22 Jun 18 Location: West Status: Offline Points: 25	Post Options Post Reply Quote RedOctober2018 Report Post Thanks(0) Quote Reply Posted: 30 Jun 19 at 10:24PM
	procedure ReleasePdfImg(const img: TImage); begin if not Assigned(img) then Exit; img.Picture.Bitmap := nil; img.Picture.Graphic := nil; end;