How to draw an ellipse with an rotated angle?

[Shalley]

Hello, there,

I have no idea how to draw an ellipse with an rotated
angle. For example, the ellipse's center is (20.0, 50.0),
two conjugate diameter pairs end-point are (35.0, 35.0),
(25.0, 55.0). I hope to use win32 API functions to finish
this drawing. Is it possible?

Please help me giving your suggestion. Tks.

 

[One Handed Man [ OHM ]]

Graphics.RotateTransform Method

 

[Jay B. Harlow [MVP - Outlook]]

Shalley,
In addition to One Handed Man's comment about Graphics.RotateTransform, you
may need to take into account Graphics.ScaleTransform &
Graphics.TranslateTransform (TranslateTransform more so than
ScaleTransform).

RotateTransform will rotate about the current origin, TranslateTransform
moves the current origin.

I find Charles Petzold's book "Programming Microsoft Windows with Microsoft
Visual Basic .NET" from MS Press to be very helpful in unraveling the
subtleties of GDI+.

Just remember order of operations is important while doing transforms in
GDI+.

Hope this helps
Jay

 

[Herfried K. Wagner [MVP]]

Hello,

Just remember order of operations is important while doing
transforms in GDI+.

That depends on the type of the operations.

;-)

 

[Jay B. Harlow [MVP - Outlook]]

Herfried,

That depends on the type of the operations.

And if you use the MatrixOrder parameter & which MatrixOrder option. ;-)

Later
Jay