Understanding the Constraint Entity(Path)
- 이혜연 (Unlicensed)
- 최규완(Eric)
Summary | Understanding Constraint Path |
|---|---|
Related Function | Curve Library Mode : Curve Library > Constraint Entity > Path > Main Constraint Path |
Type | FAQ, Tip, Example |
Q. Please explain the Constraint Path.
A. Constraint Path serves as a reference target when creating objects that refer to paths such as Curve Library or Path Linked Entity,
It serves as a reference target when creating another Constraint Entity.
In CIM, there is an object called Constraint Entity that is responsible for only the constraint of the model apart from modeling that determines the shape.
This structure captures the common constraint information of various objects created during modeling.
It is advantageous to control the model because it can be integrated and managed by linking to one Constraint Entity.
Therefore, in order for CIM's alignment-based modeling to work as intended by users, an understanding of Constraint Entity is required.
Constraint Entity of CIM is as follows, and Constraint Path is covered in this FAQ.
<Type of Constraint Entity>
Expression Entity linked to Constraint Path property is only applicable to Path Linked Entity created by
Curve Library Mode : Expression Entity > Path Linked function or
Assembly Unit Mode : Expression Entity > Path Linked function .
Similarly , Expression Entity linked to the properties of Constraint Point is a library created as Single Point or Multi-Points in Point Library Mode, or is created through Curve Library Mode: Expression Entity > Point Linked function, or Assembly Unit Mode: It is only applicable to Point Linked Entity created by Expression Entity > Point Linked function .
Constraint Path is the core object of CIM alignment-based modeling. The role of Constraint Path is to:
Role of Constraint Path
Constraint Path is created in Curve Library Mode and Assembly Unit Mode and is used for the following three purposes.
Object for alignment reference of Constraint Point
Object used for alignment definition of Section in Path Linked Entity
(In Assembly Unit Mode) Target Object to which the Curve Library will be assigned
How to define which constraint path in Curve Library / Assembly Unit Mode determines how the entire model responds when it is assigned to layout. Characteristics and Utilization of Constraint Path
The objects correlated with each constraint path are as follows.
Main Path
The properties of the Main Path are composed of Classification / Constraint Plane / Offset / Geometry.
Constraint Plane: Each constraint plane (X coordinate value) to which the start and end points of the main path will depend.
Offset : Offset value in Y / Z direction of Main Path
Objects whose Main Path is affected
Figure. 1 Constraint Plane > Main Path
The Start / End Point of the Main Path Property defines information with each constraint plane selected during creation.
Therefore, the two objects have a dependency relationship, and the X coordinate value of the Start / End Point of the Main Path is determined according to the Location (X coordinate value) of the Constraint Plane. (The two values match.)
Y / Z coordinates of each point except for X coordinates are defined by the Offset value of the Property.
Objects affected by Main Path
Figure. 2 Main Path > Constraint Point
Figure. 3 Main Path > Constraint Array Point
Figure. 4 Main Path > Rigid Path
In the case of Constraint Point and Constraint Array Point, the values of Location / Alignment / Arrangement operate depending on one Main Path.
Therefore, after layout assignment, the location is defined for the geometry of the corresponding Main Path.
Rigid Path is the standard path for tracking two Coincident Points after layout assignment, and the Main Path is used.
Rigid Path
Objects affected by Rigid Path
Figure. 5 Constraint Path & Constraint Point > Rigid Path
Rigid Path creates a path with a fixed length by connecting two Coincident Points.
At this time, two Coincident Points are tracked on the Constraint Main Path defined in the Property.
Coincident Point refers to the Reference Location defined in the Property. Constraint Point or Constraint Plane can be selected as the Reference Location, and the location of the object is followed.
Objects affected by Rigid Path
Figure. 6 Rigid Path > Constraint Point
Point can be created on Rigid Path.
Constraint Point created by referring to Rigid Path cannot be selected as a reference point for other Rigid Path creation.
Sub Path
Objects affected by Sub Path
Figure. 7 Constraint Point > Sub Path
The Start / End Point of the Sub Path behaves by referring to the Constraint Point defined during creation.
The referenced Point and each Point of the Sub Path do not necessarily match. This is because X / Y / Z Offset values are input during creation.
This Offset value can be selected to follow the Vector coordinate system of the Path, GCS or UCS through the Alignment setting.
At this time, the vector of the path is determined by the vector connecting two constraint points.
Objects affected by Sub Path
There is no Constraint Entity that is created by referring to the Sub Path information.
We looked at the reference relationship between each Path and Object. The characteristics of each path can be checked in the following documents through the assignment result in the curve alignment according to the type of path.