I 'm following this tutorial to create a pipe geometry that branches to form 2 sub branches and coverges again.
The geometry is specified by selecting a polygon and specifying the x and y coordinates (the following steps are given in the tutorial) .
Polygon 1 (pol1) 1 In the Geometry toolbar, click Polygon. 2 In the Settings window for Polygon, locate the Object Type section. 3 From the Type list, choose Open curve. 4 Locate the Coordinates section. From the Data source list, choose Vectors. 5 In the x text field, type 0 80 80 90 90 120 120 130 130 180 . 6 In the y text field, type 0 0 0 20 20 20 20 0 0 0.
Here, I don't understand why certain coordinates are mentioned twice. e.g. 80 0; 80 0. Is it required to mention twice when there is a curve?
Secondly, I would like to know how if there is an example available for specifiying curved geometries.
Also, I obseve the length of the pipe segment is in meters (the coordinate positions are specified in meters). Is it possible to specify the length in micrmeters?
Many thanks for your time and attention