[Xr] Axis orientation.

Roman Bednarek roman at mikronika.com.pl
Wed Jun 11 01:38:21 PDT 2003

On Mon, 9 Jun 2003, Carl Worth wrote:

> On Jun 9, Owen Taylor wrote:
>  > On Mon, 2003-06-09 at 09:27, Roman Bednarek wrote:
>  > >    Do you plan to add the ability to choose the Y-axis orientation?
>  >
>  > You should be able to do that yourself.
> Yup, XrScale(xrs, 1, -1) will reverse Y. Of course, one will also need
> to XrTranslate() the origin as appropriate.

  That is not so easy. You cannot change orientation with simple transform
matrix. When I do XrScale(xrs, 1, -1), I will get text drawn upsideDown, also
I think images will be drawn upsideDown. So text will have to be handled
specially, which is not quite trivial when you have text rotation and
  When I try to visualize my drawing, I always see the y-axis up, all
geametry in school is done with that axis layout, it is natural for me.
  So I think you should consider adding the possibility to choose y-axis


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