Please forgive my ignorance if I am asking a totally irrelevant question, I am still a GIS newbie.
I looked in Google and found a lot of links as of how to convert point clouds to DEMs.
I am trying to achieve exactly an opposite:
to create a point cloud from a DEM of the specific location and then
to create a 3D model of this location from this point cloud.
I didn't find one single link about it.
So is all my thinking wrong? Is there other way to achieve what I am trying to achieve?
Best Answer
You might not find good solutions, because a Point Cloud and DEM are used for two different things.
A Point Cloud represents the point of returns from usually a LIDAR survey. At a given (X,Y) point, there can be multiple points at different heights. Imagine a Single Tree. You will get the return points from both the Canopy, as well as the ground underneath it. Or Alternatively, image the points representing the Side of a building. You will have multiple points at the same (X,Y) location.
Compared to this, DEM raster is much simpler. It will have only one elevation value for a given cell. A Cell does not exactly represent a (X,Y) point either, since it has a cell width and cell height. Hence a Cell is not the exact equivalent of a point.
So if in some way you create a point cloud from a DEM, it really won't be an accurate representation of reality; Additionally it won't be equal to what a real point cloud of that location will be like.