I’m looking at some existing point cloud 3D Tile assets like Melbourne and Montreal and I’m just trying to figure out how to tell what coordinate reference system they use? The Ion docs say if I import LAS that is georeferenced it will be converted to EPSG:4326 so I’d expect lat/lon type values. But for example with the Montreal point cloud I see:
- the root has a boundingValue that is a box that has:
- center: -4.19877, 5.7869, 385.0733
- x axis: 20535.3929, 0, 0
- y axis: 0, 27448.6577, 0
- z axis: 0, 0, 409.5056 - root also has a transform that is:
- column 0: .9599, .2801, 0, 0
- column 1: -.2000, .6852, .7002, 0
- column 2: .1960, -.6722, .7138, 0
- column 3: 1253502.8130, -4294682.7306, 4530092.1469, 1
So with those large numbers on the bounding box axis and column 3 of the transform being the transposition part, I’m seeing very large values for X/Y/Z points that doesn’t seem like lat/lon. So what coordinate system is it and how am I supposed to know what CRS a given 3D Tiles file is using?