1.
Start with the project that you created in Loading and Displaying an Image.
2.
Add two buttons to your form and
name them as follows:
Name
Caption
ZoomIn
Zoom In
ZoomOut
Zoom Out
3.
Code the ZoomIn button's click procedure as follows:
Zooming Out and Zooming In (Delphi 4.0)
Take the following steps to add code that can reduce and enlarge the displayed size of the image. This demonstrates the scaling properties that are normally used for zooming in and zooming out. It emphasizes the relationship of the displayed rectangle to the LEAD RasterView control.
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1. |
Start with the project that you created in Loading and Displaying an Image. |
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2. |
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Name |
Caption |
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ZoomIn |
Zoom In |
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ZoomOut |
Zoom Out |
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3. |
Code the ZoomIn button's click procedure as follows: |
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procedure TForm1.ZoomInClick(Sender: TObject);
begin
LEADRasterView1.AutoSetRects := True;
LEADRasterView1.PaintSizeMode := PAINTSIZEMODE_ZOOM;
LEADRasterView1.PaintZoomFactor := LEADRasterView1.PaintZoomFactor + 10;
end;
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4. |
Code the ZoomOut button's click procedure as follows: |
procedure TForm1.ZoomOutClick(Sender: TObject);
begin
LEADRasterView1.AutoSetRects := True;
LEADRasterView1.PaintSizeMode := PAINTSIZEMODE_ZOOM;
if ( LEADRasterView1.PaintZoomFactor > 10 ) then
LEADRasterView1.PaintZoomFactor:= LEADRasterView1.PaintZoomFactor - 10;
end;
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5. |
Run your program to test it. |