TPC Technote

TPC Desktop for Windows
No CAD Zone Drawings

This technote explains how TPC Desktop for Windows works with drawings.  

Please refer to the Technote on Views to understand how they affect your Drawings. Refer to the Drawing Quick Start Technote for step-by-step procedures to produce a drawing. Refer to the Technote on TRV and DRV Files for information on where your drawings are stored.

Drawings

Drawings are a collection of traverses, settings and drawing objects.  When you open a drawing, Traverse PC reads the traverses, settings and drawing objects and re-produces the drawing.  If you edit the data in a traverse that is included in the drawing, the drawing reflects the new traverse data. The drawing doesn't actually hold any data like coordinates and line lengths, it just references the survey data.  This ensures that the drawing automatically reflects the current coordinates, dimensions and areas of the survey. 

The traverses, settings and drawing objects provide the basic building blocks that TPC Desktop for Windows uses to produce a drawing.  This combination is what makes producing a map or plat in Quick View so easy and fast.  You just tell Quick View how you want to draw the survey and it does the work for you.

Traverses

To include a traverse in a drawing, you tag it in the Survey View.  To exclude a traverse from the drawing, you un-tag it.  Each drawing remembers which traverses have been tagged and un-tagged.  In a typical CAD package, this is equivalent to turning layers on or off.

Settings

The settings determine how the control points, side shots and lot labels are drawn.  You can draw all the control points using the drawing settings, or draw each traverse using its own control point settings by choosing View | Use Traverse Settings from the Quick View.  The same is true of side shots and lot labels.  You can also control how the drawing labels points and lines, how many decimal places it uses for elevations, how it trims symbols, etc.

Drawing Objects

The drawing's objects include stock objects like the border and scale bar plus any text or lines you add to the drawing.  In most cases, these are not tied to a traverse or survey point.  They can be placed on the drawing based on the survey coordinates (Survey Space) or in Paper Space, which places them on the page in inches and in relation to the nearest corner.

Multiple Drawings

In TPC Desktop for Windows Standard and Professional Editions, a survey can have up to 36 drawings.  Each drawing remembers which traverses, settings and drawing objects belong to it.  You can open a drawing, work on it, then open a different drawing.  You can make a copy of an existing drawing, then add more information to the copy without affecting the original drawing.

This is a very powerful feature of TPC Desktop for Windows.  Because each drawing references the survey data, each one remains current as you add or modify traverses and survey points.  This is a welcome feature that typical CAD packages can't offer.

The tools you will use to manage multiple drawings are found in the Drawings menu of the Quick View.

A Working Drawing

As you become familiar with TPC Desktop for Windows, its important to remember that the current drawing will be affected by any traverses you tag or un-tag.  A common pitfall for new users is to finish a drawing, then leave it open while they continue to do other work on the survey that isn't related to the finished drawing.  This accidentally modifies the finished drawing.  Here are two rules to help you avoid this pitfall:

Rule 1  Before you start a new map, plat or exhibit, create a new drawing for it.

Rule 2 When you are finished with a drawing, close it and open a different one. 

This brings up the idea of a working drawing.  As you work on a survey, you want to see what you are doing.  You want to see what the imported data or rotated traverses look like.  The Quick View does this for you automatically.  When you start TPC Desktop for Windows, it creates a drawing called 'Drawing 1' or 'Quick View'.  As you tag or un-tag traverses in the Survey View, you are updating Drawing 1 (or Quick View).  Think of this as your working drawing.  Use it to evaluate the survey data, turn off side shots, zoom in to compare record data with ground data, etc.  Then when you are ready to start a map or plat, follow rule 1 above and create a new drawing.  When you are finished with the drawing, follow rule 2 and re-open Drawing 1 (or Quick View), your working drawing.

Exercises

Here is an exercise you can do to help you understand how drawings work in TPC Desktop for Windows. 

The program comes with some demonstration files. One of these is tutor1.trv. This file includes three traverses. They are Lot 2, Lot 3, and Lot 4. To practice creating and saving drawings,

1. Create a drawing from the the Survey View Quick View for each individual traverse. Name these drawings Lot 2, Lot 3, and Lot 4.

2. Create a drawing that includes all three lots and name it All Lots.

3. Keep the Drawing1 or Quick View drawing intact and leave it as the open drawing.

4. Save the file.

To check your work, close the tutor1.trv file and re-open it. This ensures that you are in the saved version of the file.

1. Go to the Quick View and make sure the Drawing1 or Quick View drawing is the active drawing and that it looks the same as it did originally.

2. Open each of the Lot drawings and the All Lots drawing and make sure they show the correct lots.

If you understand the way the program works and if you have followed the procedures above, the drawings should be what you expect. If they aren't what you expect, go back through and practice the procedural habits until you can be sure you are saving the drawings you think you are.

Temporary Drawings

When you are working in a Traverse View, the Quick View creates a temporary drawing to display the traverse.  As you enter data or do COGO tasks like inserting stations, the Quick View updates the temporary drawing to display the new points in the traverse.  Each Traverse View has its own temporary drawing.  When you close the Traverse View, the temporary drawing is destroyed.

If you have made changes to a temporary drawing, like adding a title or moving point labels, the program asks you if you want to save the temporary drawing when you close the Traverse View.  If you say yes, a copy of the drawing is added to the survey and can be opened and edited like any other survey drawing.  Note: This saved drawing does not get loaded when you go to the Traverse View it was created from.  The Traverse View Quick View always displays a temporary drawing.  To re-open your drawing, go to Drawings | Open Drawing.

The  Views technote describes the interaction of the Traverse View and Quick View in more detail.