PinPoint
The PinPoint ribbon displays when you click PinPoint 
on the Common toolbar or when you select Tools > PinPoint. PinPoint controls are active when any command prompts you to enter a point. The PinPoint Ribbon lets you to enter precision coordinates relative to the selected coordinate system,
and precision coordinate offsets relative to any point in the model.
You can change the position of the origin used for the coordinate readouts by clicking
Reposition Target 
on the ribbon and then clicking a new position in the active view. You can define
the target position by entering the coordinates, or by defining a precision point
found on existing geometry. As you move the cursor around, PinPoint displays the distances between the cursor and the target position. The target is
your way of entering Delta positions.
You can lock one or more coordinate positions by entering the coordinates in the fields. You can also use the F6, F7, and F8 keys to lock the East, North, and Elevation coordinates. For example, you can position your cursor so that it finds the axis of a pipe, and then press F8 to lock the elevation coordinate to the elevation of that pipe.
-
The coordinate system selected on the PinPoint ribbon is called the active coordinate system. All commands that have functions that reference a coordinate system use the active coordinate system.
-
You can choose to work with rectangular, spherical, or cylindrical coordinates.
-
You can define a temporary coordinate system with an origin and axis directions different from those of the global coordinate system or the available auxiliary coordinate systems you have defined in the Grids task.
SmartSketch Points
When a command prompts you to select a point in the model, the software automatically starts SmartSketch point location. When you are near a SmartSketch point, the software highlights geometric objects and displays a small glyph indicating the specific type of precision point. When you click to enter the point, the precision point's coordinates, type, and objects are supplied to the command. Many commands create associative point relationships that maintain the precision point location if the geometric objects are modified.
To understand the modification behavior of the different design objects, it is important to understand when the software creates associative points,
-
Key points on connection ports, such as piping nozzles, conduits, HVAC, and foundation ports.
-
Key points on geometry, such as end points, divisor points, points along a linear object, and the center of a circle.
-
The intersection point of two linear objects, or a point along the intersection of two planes.
-
Linear relationship points. When a command prompts for two points, you can use the points to create a line parallel or perpendicular to another linear object or axis.
You can only locate SmartSketch points on objects that have been added to the SmartSketch list. You can add objects to this list automatically by hovering over the object for the designated dwell time, or you can adding objects to the Smartsketch list manually by pressing CTRL+D and selecting objects. Manually adding objects to the list is useful if your model is so dense that it is hard to locate the SmartSketch point on a specific object of interest.
You can lock and unlock relationships to keep track of SmartSketch points as you search for other points in the model. To lock a relationship, wait until a relationship indicator displays and click click the middle mouse button. To unlock a relationship, click the middle mouse button again. Locking and unlocking relationships is also helpful if you want to isolate points in a dense model.
Add to SmartSketch List 
allows you to control the behavior of the precision point location. This command
displays the Add to SmartSketch List Ribbon.
SmartSketch Options 
displays the Options dialog box, which allows you to specify the SmartSketch points that you want the
software to locate.
What do you want to do?