Hi
I am rotating a weather map to make the 0° meridian vertical. I use Paint.NET to work out I need to rotate the image 10° clockwise to make it vertical. After loading the PNG image I apply a rotation of 10° clockwise to it by:
ImageEnView.Proc.Rotate(350,ierBicubic,-1);
This results in an anti-clockwise rotation of 10° as best I can estimate it (see image 1).
By trial and error I change this angle to 336° (?) and I get the correct rotation and the meridian is vertical (see image 2) but the component view looks odd.
ImageEnView.Proc.Rotate(336,ierBicubic,-1);
I have written a very simple test harness to see if I can duplicate this but it doesn't (see image 3), so there must be something in the code in my application. So I drop a copy of the TImageEnView component from my test harness back into my application and do exactly the same thing I did in that - but its still the same!
I have used the Rotate command before without any problem so I must be missing something. In fact in an earlier application that I wrote all that I required was:
ImageEnView.Proc.Rotate(-10,true);
Bruce.
PS One thing my test harness did highlight was a property that saved the rotation angle you applied - so that you could either add a further rotation or get back to were you started from.
I also tried rotating the ImageEnView.IEBitmap which got me hopelessly confused!
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Rotation issue
Posted - Jan 10 2014 : 06:53:44
