How you access or open a COGO command affects how the COGO dialog is initialized.
For example, if you select two points in the Points Manager, then access the Random Inverse dialog, the two selected points become the From and To points in the dialog. Know how TPC access COGO dialogs can help you become more proficient with the COGO tools.
Views that allow COGO have a pull-down COGO menu at the top of the view and a COGO sub-menu on the context menu that appears when you right click the view.
When you choose a COGO command from a View, TPC uses the data in the view to initialize that command. If you select 2 points in the Points Manager then choose COGO, Random Inverse from that view, the Random Inverse dialog displays the relationship between those two points. If you highlight a point in a Traverse View and choose COGO, Random Inverse, the Random Inverse displays the relationship between that highlighted point and the preceding control point in the traverse.
As a rule, any COGO routine that changes a survey point can be access by right clicking that points symbol or point label in a drawing and choose COGO from the pop-up menu. COGO routines that affect a traverse can also be initiated the same way, by right clicking any drawing object created by the traverse you want and choose COGO from the pop-up menu.
Once you start accessing COGO this way, you also want to learn how TPC can use the selected objects in the drawing to also populate COGO dialogs.
You can also pick graphic objects from a drawing using the > and >> buttons next to the fields in a COGO dialog. See Picking COGO From a Drawing.
COGO: Drawing View (5:17) - Do COGO right from a drawing using selected drawing objects.
Accessing COGO Commands From the TPC Desktop
When you access COGO from the TPC Desktop main toolbar or menu, TPC opens the COGO dialog without initializing it's data. If the COGO command has already been opened, it's data is redisplayed when the dialog is opened. Once the dialog is opened, you can change the data you want or work with the data that is already there. This toolbar just provides a common place to access many of the most popular COGO commands.
Presetting Distance and Direction Type
When TPC opens a COGO dialog, it looks to see if you opened it from a view that references a traverse. If you did, TPC uses that traverse's distance and direction type for the dialog. If not, TPC uses the distance and direction types of the survey to initialize the dialog. Many dialogs let you override the distance and direction types with the Show Options button.
Let's look an an example. Suppose you open the Random Inverse dialog from a geodetic traverse. TPC sets the distance and direction types of the dialog to the geodetic settings of the traverse. The dialog now reports geodetic inverses. If the traverse had used grid types, the dialog would display grid inverses.
You will want to remember that you can always pre-set a COGO dialog you open to the survey's distance and direction type by opening the COGO dialog from TPC Desktop's Main Menu or COGO toolbar.
For some COGO dialogs, the distance and direction types must match, meaning they must both be either geodetic or non-geodetic types. If you try to mix them in a COGO dialog that requires them to be the same (most do), TPC will warn you at several points along the way. See COGO Dialog Distance and Direction Types.
