Hi all.
I'm trying to create some real-world terrain for the first time out (a LOT of learning today) and running into a roadblock.
I've downloaded a heightmap downloaded from USGS (
https://apps.nationalmap.gov/downloader/#/) which I've imported. It works well!
The metadata places it on the TG planet (though not where I'd expect). I modified the "Lat long at Apex" in the planet node to bring the map to 0,0,0 to work with, as suggested by the documentation and these forums. All good so far.
Where things started to break down for me is trying to match up a color image map to the heightfield. The color image is a subset of the heightmap from USDA National Agriculture Imagery Program (NAIP), found in the same search as heightmap.
I downloaded the .jp2 image and imported into TG with the Geog Image Map shader.
Despite having metadata in the info tab and values visible in all the georeference fields, the image is placed with lower left corner at 0,0,0.
A few observations:
1. NESW corner latlong data seems to be in meters as opposed to degrees, like the heightfield
2. NESW corner latlong values are very big. They do not seem to be UTM data (no zone is able to be specified in TG, that I can see - how are these values calculated?)
3. I can switch between the Georeference and Position Explicitly radio buttons with no discernible change in the position of the image.
I *can* put values into the Position Explicitly fields to move the image map around, but I'd just be guessing to get a match with the correct position in relation to the heightfield.
....
There is SOOO much metadata for that .jp2 image.
It has latlong info, utm info...seemingly all that's needed to place it correctly, but I need help figuring out where to enter the data.
The Geo image map shader corner latlong data doesn't seem to be able to be modified, and I'm not sure how to convert the metadata from the web into the XZ positional data to place the image exactly where I need it.
Can someone pop these 2 images (links below) into a project and see if they match up for you?
Thank you!
Mike
heightfield:
https://prd-tnm.s3.amazonaws.com/StagedProducts/Elevation/13/TIFF/n47w123/USGS_13_n47w123_20210615.tifcolor map:
https://prd-tnm.s3.amazonaws.com/StagedProducts/NAIP/wa_2015/46122/m_4612256_ne_10_1_20150729_20151123.jp2meta data for .jp2 file:
https://www.sciencebase.gov/catalog/file/get/5828231fe4b01fad870f73c0?f=__disk__ca%2F85%2Fa8%2Fca85a84bdf1afd04315f2f9d5ee7da6c678bae6b&transform=1&allowOpen=true