Terrain feedback

Using Lands, and testing Terrain for the first time, because I could need it right away.
Some questions / remarks:

  • Terrain can be created from curves or points. When the input curves/points are then changed, Terrain does not update, neither with history on nor by running laUpdate.
    Can this be right? That’s counter-intuitive and impractical.

  • So, to edit the existing terrain it’s edit points must be turned on. There are various editing tools, but none to add / delete / copy existing ones. Am I missing something? Does that mean I have to completely re-create the terrain when the input point cloud / curves change?

  • There could be an ‘Add’ button, too in this panel:

  • laTerrainAddHole: the sides of the hole are not created, also when ‘Base’ is turned on. A bug I assume.


There’s something really broken about this. For a small project, I’d need a terrain looking like this (Nurbs box, boolean difference with the building perimeter):

And this is what laTerrain generates (with 2 subdivisions):

  • I also noticed it is not possible to snap to the terrain mesh points. I also tested a normal mesh box - snapping works there, so it’s a laTerrain problem.

I have to say, in it’s current state, laTerrain is not ready for prime time. I’d love to have such a tool, though.

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Hello! Thanks for your feedback. About your doubts:

  • You can add new curves/point clouds to an existing terrain using the “Add contour curve” option, available from the context menu, the Lands toolbar and the dropdown menu:

  • Curves/point clouds used as elevation data are not linked to the terrain, so you are right, if you modify these objects after using them on a Lands Terrain, the changes have no effect on the terrain. You can edit the grip points instead, or delete and add again the curve/point cloud

What you are trying to get doesn’t look like a terrain to me, maybe Lands Terrain is not the right tool to achieve that shape. Though, here are some tips that can help you:

  • Lands terrain uses two different methods to create the final surface: 1) the raw delaunay triangulation+boolean operations, 2) a gridded surface with custom detail. Method 1) will give sharper shapes but is more prone to failure, specially when complex curves are used on boolean operations or when two or more boolean operations use the same source curve. I think this second case is what is causing the strange result you showed. By default, when you add a hole, Lands adds a division using the hole curve so that you can texture it separately. I recommend you to delete this division, this way you won’t have two boolean operations using the same curve. It should work much better.
    You can also try to activate the gridded surface. We are working to get sharp edges on it. This work should be available in the next Lands update.

  • About snap points, we may have disabled them to get better performance, since a terrain can have millions of points. We’ll review it.

I’ve looked into the code and snap points are available for all terrain vertices. I’ve tested it and it works fine. Have you checked the “End” option on the osnap’s toolbar?


It’s the right tool, the terrain just happens to be more or less flat for the small project. It’s an existing building for which we did a quick access / facade study, and it lended itself for testing Lands terrain.

I’m using VisualArq, and the goal was to just get a terrain hatch in the sections.
Here’s the Rhino file:
test Lands terrain.zip (54.7 KB)

I found the problem:
When ‘laTerrainAddHole’ is used, it automatically creates a ‘hole’ but also a ‘subdivision’, as can be seen in the ‘Input Data’ panel:

and the resulting mesh is broken:

However, when the ‘Subdivision’ is removed
the mesh comes out allright!

What’s that ‘Subdivision’ thing anyway?

But still, although ‘End’ snapping is turned on (I never turn it off), snapping to the mesh does not work. It does for otherwise created meshes.

Best regards

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Divisions let you divide the final mesh into several meshes so that you can apply different materials to them. We saw that many users were creating divisions using the same exact boundary of a modeling operation previously applied (hole, cut&fill, path…) because they wanted to have there a different material. This is why we decided to make it easier and now Lands creates these divisions automatically. They are linked so if you modify the hole grip points, the division is also modified. If you remove the hole the division is deleted. You can also remove only the division. It works pretty well but for when boolean operations are used. There we have two boolean operations (hole and division) using the same exact body. Too many coincident vertices and edges, I guess.

In future versions we’ll probably perform divisions without using boolean operations, like we already do when the gridded surface is enabled. By the way, gridded surface is always my preferred way of working with Lands Terrains, though you can’t get 100% vertical faces.

About osnaps, that’s strange, in all the tests I did it is snapping to terrain vertices when “End” is enabled.

It was not working for “Vertex” osnap option. We fixed it.