Question
Can the length of the start and end points be maintained when the length of the Curve Library changes?
Answer
The position of the plane during shape transformation can be determined by the Alignment setting of the Constraint Plane.
The Constraint Plane is a Constraint Entity that exists only in the Curve library mode and Assembly unit mode, which are line-based modeling spaces, and it defines the start and end points of the main Constraint Path.
Since Constraint Plane is constrained to the Default Constraint Path, which is the basic path of the entire space, it can only be added within the range of the Default Constraint Path.
For a detailed explanation of the Constraint Plane, please refer to Understanding Constraint Entity(Plane)
If the unit length of the Curve Library and Assembly Unit, which are line-based modeling spaces, changes, or if the Default Constraint Path length changes during the assignment process to the higher-level mode, the position of the Constraint Plane will also change accordingly.
At this point, the Alignment setting of the Constraint Plane can define the changing position through the Alignment property.
Alignment setting of the Constraint Plane
The Alignment setting is a setting that defines how to remember the position of the Constraint Plane when the length of the Default Constraint Path changes.
There are two settings: By Ratio and By Distance.
- By Ratio : remembers the distance ratio from the start point to the Constraint Plane when the
length of the Default Constraint Path changes.
- By Distance : By Distance: remembers the distance value from a specific point defined by the
user to the Constraint Plane when the length of the Default Constraint Path changes.
Let's take a look at the difference in shape transformation based on the Alignment option using an example model.
1. Alignment : By Ratio
If the Alignment setting of the Constraint Plane is set to By Ratio, when the unit length of the Curve Library changes, the distance ratio from the start point to the Constraint Plane is remembered, and the shape changes accordingly.
2. Alignment : By Distance (Start Point / End Point)
If the Alignment setting of the Constraint Plane is set to By Distance (Start Point / End Point), when the unit length of the Curve Library changes, the distance from the defined start or end point to the Constraint Plane is remembered, and the shape changes accordingly.
3. Alignment : By Distance(User Defined)
If the Alignment setting of the Constraint Plane is set to By Distance (User Defined), when the unit length of the
Curve Library changes, the distance from the defined position to the Constraint Plane is remembered, and the shape changes accordingly.
(User Defined can be input from 0 to 1, where 0 represents the start point and 1 represents the end point.)