COMBTRI Process

To access this process:

Wireframe Tools ribbon >> Process >> Combine Wireframes.
View the Find Command screen, select COMBTRI and click Run.
Enter "COMBTRI" into the Command Line and press <ENTER>.

See this process in the Command Table.

Process Overview

Combines up to 20 pairs of wireframe model files, into a single pair of output files (a single wireframe). This process is similar to ADDTRI, however that process is restricted to combining two wireframe pair files at a time whereas COMBTRI can combine up to 20.

Note: COMBTRI does not check for interpenetration of the two wireframes, but simply combines them into a single wireframe model.

GROUP, SURFACE, and LINK fields are treated as a hierarchical topology and are remapped together rather than independently.

How does it work?

COMBTRI merges multiple wireframe point/triangle file pairs into a single output wireframe, by doing the following:

Recreating output files from scratch unless the output names are the same as the first wireframe that is specified.
Renumbering structural identifiers (PID, TRIANGLE).
Preserving triangle ordering.
Maintaining uniqueness of selected grouping fields across inputs.

How does it do this?

COMBTRI reads two or more wireframe pairs (triangle + points)
It then writes new output triangle and points files
It filters out invalid rows.
It then renumbers (reorders) triangle fields:
- TRIANGLE 1..n
- PID 1..m
Preserving input triangle order, COMBTRI writes only points referenced by valid triangles.

Implicit Fields

COMBTRI deals with implicit fields as follows:

By default, if an implicit field is present in all the input wireframe triangle files it stays implicit in the output and its value is derived from the earliest specified wireframe that has the field.
If a field is present in the input files and is a mix of implicit/explicit across wireframes it will be explicit in the output. Implicit wireframes write their default value per-row; explicit wireframes write their per-row data. Wireframes that don't have the field at all get absent.
If a field is specified as a ZONEn field, it is always forced to be explicit in the output regardless of whether all inputs are implicit. Wireframes without the field get absent values.

Input Files

Name

Description

I/O Status

Required

Type

WIRETR1-20

Input wireframe triangle file 1 to 20.

Note: The first input wireframe (WIRETR1/ WIREPT1) can have the same names as the output files (OUTTR/ OUTPT) to append more wireframes to the first wireframe.

Input

Yes

Wireframe Triangle

WIREPT1-20

Input wireframe point file 1 to 20

Input

Yes

Wireframe Points

Output Files

Name	I/O Status	Required	Type	Description
OUTTR	Output	Yes	Wireframe Triangle	Output wireframe triangle file.
OUTPT	Output	Automatically detected if not specified (if same name without suffix is found), otherwise must be specified.	Wireframe Points	Output wireframe point file.

Fields

Name	Description	Source	Required	Type	Default
ZONE1-5	Field(s) to keep unique.	IN	No	Any	Undefined

Example

!COMBTRI &WIREPT1(ZON1PT), &WIRETR1(ZON1TR), &WIREPT2(ZON2PT), 
         
&WIRETR2(ZON2TR), &OUTTR(TOTPT), &OUTPT(TOTTR), *ZONE1(_GUID)