Any splines, no cleanup
Open lines, closed loops, contours with gaps — they all work as they are. There is nothing to close, join or clean up first.
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Beta 3ds Max 2023 · 2025 · 2026 Version 0.1.79
SplineGround
Terrain, roads and platforms from the splines already in your scene.
SplineGround
Features
Smooth, with no seams
The plugin builds one continuous surface across all your lines at once, so the terrain has no seams, steps or stripes.
A clean mesh
The mesh is finer where the lines run and lighter in open areas. No long, stretched triangles are left along the edges.
Platforms and roads
Model a platform or a road as an ordinary Editable Poly or Editable Mesh object — the plugin fits it into the terrain and builds the slopes at the angle you set.
Cutouts and zones
Use a closed spline to cut a hole, trim the terrain to the site boundary or mark an area for its own material. A cut-out piece can come out as a separate object.
Ordinary 3ds Max geometry
The result is an ordinary mesh: modifiers like UVW Map and Edit Poly work on it, and you can collapse it, edit it and render it with anything.
What SplineGround does
SplineGround is a 3ds Max object that builds terrain from splines. You add contour lines, road centerlines or simple sketch curves, press one button, and get a surface that passes through all of them.
The best part: it does not need perfect data. Contours can be open, broken or come from different sources. There is no heightmap resolution to choose and no special handling for the edges — the plugin puts everything together into one smooth surface.
How it works
- Collects the lines. The plugin goes through every spline you added and takes points with their heights.
- Builds a mesh. A mesh of triangles is laid out around the lines: finer close to them, coarser further away. Overly stretched triangles at the edges are trimmed off.
- Works out the heights. Every point of the mesh gets a height so that the surface flows smoothly through your lines, with no seams or steps.
Working with it
- Create a SplineGround object and add your contours to the Splines list.
- Press Generate Surface.
- If you need them, add platforms and roads to the Platforms list, and cutouts and material zones to Ground Works.
- Press Generate Surface again. When you are happy with the result, the terrain can be collapsed into an ordinary mesh.
Tip. Draw one spline around the whole site at the height you want the edge to be, and add it to Splines. The plugin then does not have to guess what happens beyond the last contour, and the edge comes out exactly where you want it.
Beta
SplineGround is currently in beta and keeps improving. The trial is the full plugin with no limits, so the easiest way to see whether it suits you is to try it on your own survey data.
System requirements
| Software | Autodesk 3ds Max 2026, 2025 or 2023 (a separate file for each) |
|---|---|
| Operating system | Windows 10 or 11, 64-bit |
| Processor | Any modern processor; more cores help with large scenes |
| Memory | 8 GB or more; 16 GB or more for large, detailed surveys |
| Installation | Copy one file into the 3ds Max plugins folder |
Frequently asked questions
Do my contours have to be closed?
No. The plugin reads heights from every line as it is, so even one open contour already gives you a strip of terrain. A closed spline around the site helps you control the height along the edges, but it is optional.
What do I make platforms and roads from?
Ordinary Editable Poly or Editable Mesh objects. Model the platform or the road surface, add the object to the Platforms list, and the plugin fits it into the terrain.
What happens to the terrain when I change a spline?
Press Generate Surface again and the terrain is rebuilt from the updated lines. Your splines stay ordinary scene objects that you can edit at any time.
Which 3ds Max versions are supported?
3ds Max 2026, 2025 and 2023 — pick yours on the download page. If you need another version, write to us.