If you select inappropriate feature types, PC-DMIS displays this message on the Status bar:
"Cannot construct [feature]. Combination of input features not accepted."
To construct a curve:
Open the Construct Curve dialog box (Insert | Feature | Constructed | Curve).
From the Feature list, select the desired set.
Select the Use tolerance check box and then set the value in the Thinning Tolerance box. Update the Thinning proportion value if necessary. For details, see the "Thinning Parameters" topic in this documentation.
Edit the control points if necessary. For details, see the "Edit Control Point" topic in this documentation.
Click the Create button.
All constructed curves start out as DEPENDENT curves and must be created from a single input, a set. The set can be one of three types:
A measured set
A constructed set
A scan containing a single row of points. (See "Constructing a Set of Features".)
The input set must contain at least four features or points (in the case of a scan).
The resulting curve depends on the order that the features are added to the set (first to last).
You can also construct a curve by simply selecting multiple features from the feature list box rather than selecting a constructed set from the list. In this case, the command's INPUT_TYPE field will be empty when viewing the command in the Edit window.
The following paragraphs describe the options for constructing a curve.
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