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Note: The fixed object or point can be moved while editing geometry, but will not move when constraints are placed upon it.
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1. To fix an object, activate the Fix Geometry constraint and select the object you want to fix.
The anchor symbol indicates that the object is fixed.
2. Now if you apply a constraint, such as Parallel in this case, the non-fixed line will move, regardless of the selection order.
3. For another example of this tool, start with a line and arc and apply a Connect constraint (see Connect Constraint).
4. The result is that the line maintains its orientation and is tangent and trimmed to the arc.
5. Undo this constraint, and apply a Fix Geometry constraint to the line's endpoint.
Now the anchor symbol is attached to the endpoint.
6. Now apply the Connect constraint. The endpoint stays fixed, and the orientations of the line and arc are modified.
7. If you edit the line or arc, such as changing start or end angles, the fixed point will not move, and the other objects will move or rotate accordingly.
