sngDMT
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Get coords from objects (for triangulation), input points of POINT, LINE, 3DPOLYLINE or BLOCK-type objects or external coords, are available. It is possible to apply a filter (according to layer) on a object,  that means only coords of objects in these layers are used.

Area for finding the coords, it is possible to search through whole sketch, or the user can select objects manually.

Breaklines are sorted to soft and hard. The soft ones only define the shape of triangles, the hard ones also guarantee non-smooth transition during contour creation. It is possible to choose breaklines manually from the sketch, or from the list of used layers. When option Layers is used, all objects from selected layers are used. Usable objects for breaklines are Line segments and 3D curves. Other objects will be ignored. Coordinates of breakline edges are added to the set of points, used for triangulation. If the breaklines are adjacent, they need to be connected with joint vertex. Before the creation of TIN, a test of breaklines geometry takes place. Found problems (crossing, T-connection, overlapping) are fixed and written into error log.

Skip TIN (Triangle mesh) is used for specification of an area where no TIN will be made. 

Exterior (2D/3D polyline) defines outer edge. Interior (3D polylines only) is used to define islets (holes).

Concave envelope of TIN, Remove outer triangles: When this function is used, outer triangles are checked in loop to make sure that none of them has side, longer than is set. The Factor option is computationally faster.

Ignoring objects with Z=0, applies to input set of points and breaklines.

Surface name: Created object will contain this name.

Preview:  Rendering of TIN is done in a new window.

Note: Creation of TIN is not suitable for overhangs, bridges, tunnels etc.