Dynamic Constraint Lines: Snap Points

Snap points are used to position a new entity relative to existing entities.

For example:

Snap points are used to indicate endpoints and center points.
When you create a new line, you can extend the line to the snap point. When you click to define the line, the line will "snap" to the snap point.
When you create a geometry, you can use snap points to define geometry points.

The endpoint of line 1 will snap to the center point of the circle.	The endpoint of line 2 will snap to the end point of line 1.	The endpoint of line 2 will snap to the center point of line 1.

Note: When you use Dynamic Constraint Lines to help you position a new entity, the new entity will be constrained to either the existing entity or the X-Y axis. When the new entity is positioned relative to an existing entity, a mutual constraint relationship is created with the existing entity. If required, you can subsequently break an entity's constraints to make it independent of all other entities and the X-Y axis.