Save Current View to image

[fisad]

Hi:

How I can save the current view, not the complete cadimage, to a image? For example, I have a drawing zoomed and I want to save that view to an image.

[support]

Hello,

Please, specify, do you need to save the zoomed area to a raster image (BMP, JPEG)?


Mikhail

[fisad]

Yes... Mikhail!

[fisad]

I think the support of these products is really dead. Shame invest in a product that promised much and get zero response from a businessman

[support]

Hello,

We apologize for the delay in answering.

The code below saves the current view to a BMP image:

Code: Select all

procedure TForm1.SaveToBMP(const AFileName: string);
var
  vGr, vGrOut: TGraphic;
begin
  vGr := TMetafile.Create;
  vGrOut := TBitmap.Create;
  try
    ActualGraphic(vGr);

    vGrOut.Width := 600;
    vGrOut.Height := 800;
    DrawTo(vGrOut, Rect(0, 0, vGrOut.Width, vGrOut.Height), vGr);

    vGrOut.SaveToFile(AFileName);
  finally
    vGr.Free;
    vGrOut.Free;
  end;
end;

Note: this code uses ActualGraphic() method that is implemented in Viewer demo application (Unit1.pas).


Mikhail

[fisad]

Thanks!!

[slbarker]

sorry to hijack this thread but I have the same problem. I have tried to print the resulting bmp to see what is going on but it is failing before that with an error on the line that assigns the picture from my TsgImage to the TsgDrawingNavigator so I can use your ActualGraphic function.

The error is: Invalid pointer operation

Code: Select all

        
        vGr := TMetafile.Create;
        vDn := TsgDrawingNavigator.Create(nil);
        try
          vDn.Picture.Assign(frmMain.sgPaintBox.Picture);   // sgPaintBox is a TsgImage. this line fails.
          ActualGraphic(vDn, vGr);
          W := Printer.PageWidth / vGr.Width;
          H := Printer.PageHeight / vGr.Height;
          if W > H then W := H;
          PW := Round(W * vGr.Width);
          PH := Round(W * vGr.Height);
          Printer.BeginDoc;
          Printer.Canvas.StretchDraw(Bounds((Printer.PageWidth-PW) div 2,
            (Printer.PageHeight-PH) div 2, PW, PH), vGr);
          Printer.EndDoc;
        finally
          vGr.Free;
          vDn.Free;
        end;

[support]

Hello,

An Invalid Pointer exception is thrown by the memory manager when it tries to free invalid memory. It seems that your program is trying to free an object that has already been destroyed. The Call Stack for this error could give us more information about the issue. Please, post it here.

By the way, you can use TsgDrawingNavigator.ActualGraphic property to print a current view:

Code: Select all

uses
      ..., sgDrawingNavigator, Printers;


procedure PrintImage(AGraphic: TGraphic);

const PO: array[Boolean] of TPrinterOrientation = (poPortrait, poLandscape);

var
  W, H: Double;
  PW, PH: Integer;
  R: TRect;
begin
  with Printer do
  begin
    Orientation := PO[AGraphic.Width > AGraphic.Height];
    W := PageWidth / AGraphic.Width;
    H := PageHeight / AGraphic.Height;
    if W > H then W := H;
    PW := Round(W * AGraphic.Width);
    PH := Round(W * AGraphic.Height);
    R := Bounds((PageWidth - PW) div 2, (PageHeight - PH) div 2, PW, PH);
    Printer.BeginDoc;
    try
      Printer.Canvas.StretchDraw(R, AGraphic);
    except
      Printer.EndDoc;
      ShowMessage('Problem while printing, please try again.');
    end;
    Printer.EndDoc;
  end;
end;

...
PrintImage(vDn.ActualGraphic);

Mikhail

[slbarker]

Thanks, I found the solution to the error. I needed to set the DrawingNavigator's Parent first.

Your suggestion to use the DN ActualGraphic property is interesting. I wonder if there is also a way not have to use a DrawingNavigator at all, given that the zoomed image is already in a TsgImage control. So can you suggest a way to save the zoomed picture of a TsgImage directly to a bitmap file?

Thanks,
Steve

[support]

Hello Steve,

TsgCADImage is not a control, it is an object that stores the drawing data and can be drawn on the screen, metafile or printer. It is possible to draw a specified part of the loaded drawing on some canvas using TsgCADImage.DrawRect procedure. The DC parameter specifies the Windows GDI handle to the device context the canvas must draw into. You can use TImage Canvas to draw a part of the TsgCADImage, then save the drawn part to a bitmap.


Mikhail