tcpMDT

Create triangulated surface (TIN)

Updated on 4 June 2026 tcpMDT Leer en español

Generates a TIN triangulated surface from the MDT point cloud in the active drawing and draws it in CAD. The surface file (.sup) is automatically saved in the same folder as the .dwg file.

Optionally accepts breaklines to honour terrain discontinuities (road edges, ditches, walls, etc.).

Prerequisites: The MDT plugin must be loaded, the .dwg file must be saved with a name, and there must be at least 3 non-collinear MDT points. If the drawing has no name, the .sup file cannot be created.

Note: If a .sup file with the same name already exists, the operation is not performed. Use the name parameter to specify a different name, or manually delete the existing file.

Parameters

Parameter	Type	Required	Default	Description
`name`	text	No	DWG file name	Name of the surface and the resulting `.sup` file.
`breakline_layers`	text	No	—	Layers containing breaklines, separated by commas. Example: `CAMINO,BORDILLO,CUNETA`. Polylines on those layers act as constraints in the triangulation.
`max_side`	number (m)	No	`0` (no limit)	Maximum triangle side length. `0` = no limit. Useful for removing large triangles in areas with no data.
`layer`	text	No	Configuration prefix + name	CAD layer where the triangulation will be drawn.
`draw_as_3d_faces`	boolean	No	Value configured in MDT	`true` = draw as 3D faces (better for visualisation); `false` = draw as lines (better for editing).

Result

Two outputs are created: (1) the .sup file in the DWG folder and (2) the triangulation drawn in CAD. The assistant returns: name, number of triangles and vertices, breakline segments, 2D and 3D area, elevation range, layer and file path.

Tip: Always include the breakline layers to obtain a more accurate triangulation in areas with sharp slope changes. After creating the surface, you can generate contour lines directly with Generate contour lines.

Example prompts

You can ask the assistant things like:

Create the triangulated surface of the drawing
Generate the surface with the name "Parcela_Norte"
Create the surface using the breaklines from layers CAMINO and CUNETA
Triangulate the drawing points with a maximum side length of 50 metres
Generate the surface with breaklines from layer MURO and draw it as 3D faces
Create a surface called "original_terrain" to use as a base in the volume calculation