Re: Text extent implemented (partially)

[Michael Goffioul]

On Tue, Mar 9, 2010 at 2:01 PM, Ben Abbott <address@hidden> wrote:
> I find it confusing to when there are multiple coordinate systems. Perhaps it 
> is best to give an example?

Yes indeed.

>
> For Matlab (left, bottom) of the text extent is with respect to the axes 
> coordinate system, with the units specified by the text object.
>
>>> plot(1:10)
>>> h = text (5,5,'Hello World');
>>> get (h, 'extent')
>
> ans =
>
>       4.9517       4.7522       1.3862      0.41983
>
> The same example in Octave gives ...
>
> octave:7> get (h, 'extent')
> ans =
>
>  -0.00000   0.00000   1.86636   0.52585

Currently in octave, the first 2 values of the extent property will
always be the lower
left corner of the axes box in Units coordinates. In the above
example, the axes is
in 2D mode and I guess the autoscale sets X and Y limits to something
like [0 10].
This means that the lower left corner of the axes boxes is at data
coordinates [0 0].
If you set text Units to "pixels", the first 2 values will be [1 1]
(pixels cooredinates are
always 1-based).

Michael.