cesium load gltf not int the right position - cesiumjs

cesium load gltf, not in the right position
I'm trying to load a model of house, by cesium. I have already set the position of the model by specified the matrix of the model, but the model is not in the position where I put it. I found the model origin is not in or near the model itself .
Someone suggested, modifying the gltf file, to make sure the origin is near or in the center of model should work, but how can this be done through programming? I don't want to edit thousand gltf models.

Maybe some with this links will help:
https://cesium.com/docs/on-premise/tilers/models/
https://github.com/AnalyticalGraphicsInc/czml-writer/wiki/Model
By the way, how bad is the wrong position? Are you sure that didn't inverted latitude and longitude?

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Openlayers GIS - Georeferenced DEM(GeoTIFF) not positioned correctly in Map (OpenStreetMap)

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I've created OSM layer with it's default projection & I'm setting view after raster source is loaded, using source.getView()
I referred to Raster reprojection examples in the Openlayers website, but wasnt able to solve this.
Does anyone have an idea on how to resolve this?
As Mike had suggested in the comments, this issue was happening since even though the projection name was identified from the raster - Eg: "EPSG:3237", the Openlayers library doesnt have the projection definition(what it actually means), so now I'm fetching proj definition from epsg.io & registering in proj4 defs. Now it works perfectly!
Thanks Mike.

How to create a geojson file from an image overlay?

I am looking for a way to create a geojson file from the distributions of the health sectors in my region which are different than any political division readily available on osm:
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Which is the fastest way to approach this?
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Another solution is to find a shape file (maybe this is correct) and simply convert the .shp into a geojson.

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Is there a method from Autodesk Forge to find out the location of each point from the corner of the building like the picture I attached?
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https://forge.autodesk.com/blog/show-mesh-triangles-data-hittest

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Link
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I would like to display some reference lines in the viewer that are not shown by default when a drawing is uploaded to Forge.
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Is there a way to get the transformation matrix that was applied to the model, so I can align the coordinates of my reference lines with the coordinates of the model in the viewer?
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