It sounds weird. Not only I rotated text at arbitrary angle, but I've done arbitrary affine transform with text, and, as far as I remember, the quality of font rendering was quite good.
As you did not show any code rendering the text, I have no idea why it screwed up quality of rendering. Better ask the author of this code. I would guess it's the problems of option properties of the instance of
System.Drawing.Graphics used. Better yet, if this is really a problem, throw out this lousy code and write your own.
I'll give you the idea. In the method
System.Windows.Forms.Control.OnPaint you have to override, you will given the instance of
System.Drawing.Graphics passed in event arguments parameter. Perform required
affine transform on this instance:
Graphics.Transform Property (System.Drawing),
Matrix Class (System.Drawing.Drawing2D) (in particular, look at
Rotate* methods).
Also, pay attention for the members related to rendering quality, read about them:
Graphics Class (System.Drawing).
—SA
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