Greg, Thank you for that information. I'll put together some example code and post that shortly.
As far as upgrading Proj4; because we build Proj4 statically in our custom build, it's not a trivial task to upgrade versions. Also, I think there might be compatibility reasons why we've stuck with 6.3.1 up until now. But if NAD83 realization transformation functionality has been expanded and improved in later versions, it might be worth it for us to upgrade. I was wondering, judging by the contents of the proj-datumgrid packages I've found online, it looks like Proj4 did not support any NAD83 realization transformations besides 1986->HARN before at least Proj4 7.0. Do you happen to know if this is true or not? I'm having trouble confirming this online, On Mon, Jul 15, 2024 at 11:06 AM Greg Troxel via gdal-dev < gdal-dev@lists.osgeo.org> wrote: > You didn't, as far as I can tell, post the code that is not doing what > you want. Or perhaps turn that code into a small test case program. > People reading that would be able to be more helpful, and the code > example could help others. > > Proj 6.3 is quite old. I recommend you update to the latest release > and the latest gridshift package before debugging further. I am not a > gdal or proj maintainer, but I am packager for both, and often rant > about NAD83 and WGS84 issues. In general, proj has a hard time dealing > reasonably with WGS84 (which you aren't at the moment), and the > transforms among the various NAD83 are complicated. I am not the least > bit sure they are all in the epsg dataset. > > You should very likely be using projinfo, and also thinking about how > you are conveying the area of applicability when setting up the > transform. > _______________________________________________ > gdal-dev mailing list > gdal-dev@lists.osgeo.org > > https://lists.osgeo.org/mailman/listinfo/gdal-dev > > -- David Klaus Carlson Software Disclaimer The information contained in this communication from the sender is confidential. It is intended solely for use by the recipient and others authorized to receive it. If you are not the recipient, you are hereby notified that any disclosure, copying, distribution or taking action in relation of the contents of this information is strictly prohibited and may be unlawful.
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