How can I Incrementally add data to an exist point clouds file? about potreeconverter HOT 6 CLOSED

Sounds like a good idea. Will take some time, though.

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Hi,

I try to figure out how to update the octree, but the first thing I must to understand is cloud.js file, i know that you use index of bbox vertices to indice child node but i dont understand why they do not start with 0 (root). By ex, what does this mean r620020 ? is it a nested octree which start from 6th level?

Otherwise, i try to understand how you create the octree, did you use top-down to create leafs, then bottum-up to creat LOD?

Thank very much!

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The numbers indicte the index of the child at level x.
r: root node
r0: first child of the root node
r6: seventh child of the root node
r62: third child of r6
and so on

To create the octree, you first specify the bounding box and the depth.
Then, points are added to the octree. When a point is added, it is checked if it can be added to the root node without being too close to one of the other points inside the root node(spacing). If it's too close, it'll be added to one of the children of the root node, depending on it's location. This check is then repeated down to the leaf until a node is found where that point can be added.
All of this happens in the PotreeWriter class.

For incremental conversion, there needs to be a function that can resize the octree and reorders the points accordingly.

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Thank you, it's more clear for me!

Other questions: what's happenning if new comming point does not touch to any node because of check condition of maxLevel and spacing? is it taken into account some where in octree?

do you know a good fucntion to compute the spacing according to point density and maxLevel?

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Other questions: what's happenning if new comming point does not touch to any node because of check condition of maxLevel and spacing? is it taken into account some where in octree?

In that case, the point is discarded.

do you know a good fucntion to compute the spacing according to point density and maxLevel?

Not yet but if you've got good ideas, tell me! One thing that came to mind is to automatically calculate the spacing according to the volume and if it turns out that the spacing is too small or too big, then all existing octree nodes can be split or merged and the points reordered.

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I've created a new issue for this since it is becomming a high priority issue:
#138

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