MAKEDTM Process

To access this process:

Wireframe ribbon >> Process >> Wireframe Processes >> Make DTM.
Enter "MAKEDTM" into the Command Line and press <ENTER>.
Display the Find Command screen, locate MAKEDTM and click Run.

See this process in the Command Table.

Process Overview

MAKEDTM generates a DTM file from points data in a file, which is optionally subdivided or constrained using one of the following inputs:

Closed perimeter data
String files

Point coordinate fields will be automatically detected if possible, but can be reviewed/edited using the Fields tab.

Note: For interactive DTM creation from loaded string or point data, see dtm-create ("md").

Make Diagonals Consistent

You can form a DTM from one or more input string or points objects (or a combination). However, where point data is common between multiple objects (meaning there are coincident data points in the set used to form the DTM), it is possible for surface triangulation to be performed in a different way, and often unexpectedly so, compared to the outcome if data were sourced from a single object (without coincident points).

To mitigate this possibility, the Make Diagonals Consistent option can be checked to ensure the surface generated between disparate data sets is performed identically, ensuring the combined DTM matches the triangulated output from a single data object input.

Note: Selecting this option can introduce a performance hit, so where large coincident data overlaps are known to occur between input objects, it may be more efficient to combine data first into a single object (say, using the Copy from Object(s) screen) before generating a DTM.

Input Files

Name	Description	I/O Status	Required	Type
PERIMIN	Input perimeter file containing XP,YP,ZP,PTN, PVALUE fields. Closed strings will be used as boundaries to the triangulation, and may be included in the triangulation if @INCPERIM is 1.	Input	See desc	Strings
STRINGIN	Input string file containing XP,YP,ZP,PTN and PVALUE fields. String segments are included in the triangulation as 3D edge constraints, breaklines. Strings may be open or closed.	Input	See desc	Strings
POINTSIN	Input point file containing XPT,YPT,ZPT fields.	Input	See desc	Points

Output Files

Name	I/O Status	Required	Type	Description
WIRETR	Output	Yes	Wireframe triangles	Output wireframe triangle file.
WIREPT	Output	Yes	Wireframe points	Output wireframe points file.

Fields

Name	Description	Source	Required	Type	Default
XPT	X field in input file	PERIMIN, STRINGIN or POINTSIN	Yes	Numeric	Undefined
YPT	Y field in input file	PERIMIN, STRINGIN or POINTSIN	Yes	Numeric	Undefined
ZPT	Z field in input file	PERIMIN, STRINGIN or POINTSIN	Yes	Numeric	Undefined

Parameters

Name	Description	Required	Default	Range	Values
BOUNDARY	Boundary specifier for perimeters: 0 - outermost strings are an external boundary. 1 - outermost strings are an internal boundary.	No	0	0,1	0,1
INCPERIM	Include perimeter strings in the triangulation : 0 - perimeter strings are NOT included within the triangulation. 1 - perimeter strings ARE included within the triangulation.	No	1	0,1	0,1
TOL	Tolerance distance below which points can be moved to avoid sliver triangles around breaklines	No	0.00001	Undefined	Undefined
FLATTRI	Avoid flat triangles: 0 - do not avoid flat triangles. 1 - flip connection to try to avoid flat triangles.	No	0	0,1	0,1
TRIM	Trim edge triangles: 0 - do not trim edge triangles. 1 - iteratively remove triangles from the edge of the dtm until the constraints from @TRIMANG and @TRIMLEN are met.	No	0	0,1	0,1
TRIMANG	Minimum (2D) angle allowed in an edge triangle to avoid trimming	No	0	0,360	Undefined
TRIMLEN	Maximum (2D) edge length allowed in an edge triangle to avoid trimming	No	0	Undefined	Undefined
CREST	Add automatic crest spurs to minimise upper plateaus: 0 - do not add crest spurs. 1 - add crest spurs.	No	0	0,1	0,1
CRESADJ	Vertical distance to offset the crest spurs	No	0	Undefined	Undefined
VALLEY	Add automatic valley spurs to minimise lower plateaus: 0 - do not add valley spurs. 1 - add valley spurs.	No	0	0,1	0,1
VALLEYADJ	Vertical distance to offset the valley spurs	No	0	0,1	0,1
KEY	Add automatic key spurs: 0 - do not add key spurs. 1 - add key spurs.	No	0	0,1	0,1
DIAGONAL	Manage triangulation between multiple input data objects. 0 – Do not attempt to align triangulation between different input data. 1 – Ensure triangulation between different objects is consistent.	No	0	0,1	0,1