[gdal-dev] Specify Grid Rotation for gdal.Warp() with Geolocation Arrays

[Michael Sumner]

yes I see, well you can probably set a target GeoTIFF with the geotransform
that you want - and gdalwarp to that as the target.  I don't believe you
can do that with gdalwarp directly, and I have no idea with python - and
finally I'm sorry to add irrelevant discussion - but this is interesting
and I'm going to try it out in R and C++ and would love to see a python
example too.

Cheers, Mike





On Sat, Nov 5, 2022 at 2:21 PM Brendan Heberlein <bheberlein at wisc.edu>
wrote:

> Hi Mike,
>
> regardless of the map projection, it may be desirable to have the grid
> oriented in one direction or another, e.g. due to the spatial distribution
> of data points. Although the CRS/SRS designates the coordinate axes, these
> are not always aligned with the desired grid orientation.
>
> So, basically I want to be able to specify an arbitrary geotransform array
> for the output grid. This would allow the grid to be assigned an arbitrary
> orientation within the CRS frame.
>
> Thanks,
> Brendan
> ------------------------------
> *From:* Michael Sumner <mdsumner at gmail.com>
> *Sent:* Friday, November 4, 2022 6:57 PM
> *To:* Brendan Heberlein <bheberlein at wisc.edu>
> *Cc:* gdal-dev <gdal-dev at lists.osgeo.org>
> *Subject:* Re: [gdal-dev] Specify Grid Rotation for gdal.Warp() with
> Geolocation Arrays
>
> well, the map projection does this - there are many possibilities. Or, do
> you have another geolocation array you want as the target?
>
> If you have an example I'm happy to try a few things, but I'd assumed you
> had a target map projection in mind. What kind of crs to choose depends on
> your goal, or is purely to not have north up?
>
> Perhaps there's something terminology wise I'm missing ...
>
> Mike
>
> On Sat, 5 Nov 2022, 10:50 Brendan Heberlein, <bheberlein at wisc.edu> wrote:
>
> Hi Mike,
>
> thanks for the response.
>
> Can you clarify how I would go about specifying the grid orientation for
> the output raster? None of -te, -ts or -t_srs address this.
>
>
> ------------------------------
> *From:* Michael Sumner <mdsumner at gmail.com>
> *Sent:* Friday, November 4, 2022 6:41 PM
> *To:* Brendan Heberlein <bheberlein at wisc.edu>
> *Cc:* gdal-dev <gdal-dev at lists.osgeo.org>
> *Subject:* Re: [gdal-dev] Specify Grid Rotation for gdal.Warp() with
> Geolocation Arrays
>
> that's exactly what the warper does with geolocation arrays, set the
> target extent, dimension, and crs with -te, -ts, -t_srs with gdalwarp.
>
> python will have those analogous controls for the warper.
>
> Cheers, Mike
>
>
>
> On Sat, 5 Nov 2022, 01:23 Brendan Heberlein via gdal-dev, <
> gdal-dev at lists.osgeo.org> wrote:
>
> Hello,
>
> I would like to be able to warp an image dataset using a geolocation
> array, while specifying the grid to which the output dataset is sampled.
> Specifically, I want to be able to warp the dataset to a grid which is not
> oriented North-up.
>
> Can GDAL support this currently? Or, what is the likelihood this could be
> supported in the future?
>
> I primarily rely on the Python bindings, so a solution within that
> framework would be ideal for me.
>
> Thanks!
>      — Brendan
>
>
> _______________________________________________
> gdal-dev mailing list
> gdal-dev at lists.osgeo.org
> https://lists.osgeo.org/mailman/listinfo/gdal-dev
>
>

-- 
Michael Sumner
Software and Database Engineer
Australian Antarctic Division
Hobart, Australia
e-mail: mdsumner at gmail.com
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/gdal-dev/attachments/20221105/5b4d5a09/attachment-0001.htm>