Constraints and Edit Actions

Each time you edit an entity, the existing constraints on the entity are automatically maintained. If an existing constraint does not permit you to edit the entity, then the editing function that you chose is not performed.

Note: You can press the ALT Key to draw a free sketch displaying only end point constraints, or alternatively, select the Skip all constraints checkbox in the Constraints dialog, displayed by clicking the Constraints Filter button from the Sketcher Toolbar.

When you edit entities, the existing constraints on one or more entities change the behavior of the editing function as follows:

In some circumstances, a constrained entity may not be edited.

For example: You wish to edit 3 lines so that they are horizontal. However, one of the lines has a pre-existing constraint. The constrained line will not follow the behavior of the selected tool.

When you select the Add Constraint option , select 3 independent lines, and apply the Horizontal tool , the three lines become horizontal.

Demo: Press the button below to view a short movie demonstrating the function:

However, when line B is constrained to be vertical, only the independent lines A and C become horizontal. Line B remains vertical. (Line B changes to orange as a reminder that it is constrained.)

Demo: Press the button below to view a short movie demonstrating the function:

In other circumstances, the selected entities modify their behavior to accommodate the constraint.

When you select several entities and an editing tool, such as the Parallel tool or the Normal tool , the last entity generally becomes the defining point for the position of all the entities. However, if one of the selected entities is constrained, the constrained entity becomes the defining point for the position of the other entities.

For example: You wish to edit 3 lines so that they will be parallel. However, one of the lines has a pre-existing constraint. The independent lines become parallel to the constrained line.

If all the lines are independent, the first 2 lines move to become parallel with the last line.

Demo: Press the button below to view a short movie demonstrating the function:

If line B is constrained to be vertical, the independent lines A and C move to become parallel with line B.

Demo: Press the button below to view a short movie demonstrating the function: