The previous iDraw exercises paid no attention to scale, they were focused on gaining familiarity with the concept basic technical drawing skills. When you try to draw original items on the ground, you need better scaling and layer controls.
PARP:PS has always drawn at 1:20 scale. Since the original iDraw only used pixels for the units, we had to create a scale bar that made logical sense to the user and draw things in an artificial scale. But now that we can use different units in iDraw we can have a better sense of size when we draw.
We also had to arrive at a logical layer structure. Being able to turn layers on and off is key to moving elements out of your way to focus on the drawing. So our drawings used the following layer structure:
- Elev Text
- Elevations
- SU Text
- SU
- Walls
- Tr Outline
- Baselines
- Scale Bar
- Image
This layer structure, and the major grid lines standardized on 5 instead of 6, can be copied to your computer using the instructions below. The file that you download and install will be an A-3 sized document with millimeter sized grids.
iDraw documents are packages. That is, it is really a folder, but your iPad thinks it is a document. The problem is that when you copy native iDraw documents to the Mac, the Mac doesn’t see it as a package, but as a folder. And it will copy the document over to the iPad as a folder, and iDraw won’t recognize it as a document. The trick is to make the Mac think it is a package, then copy it over, and then rename it in iTunes. So the file that I made has a .pkg extension, making it look like an installer package. Download the file here, which will start as a .zip file. Once decompressed it will be called GridA3.pkg (and the Installer might try to install it but return an error which can be dismissed). Using the file sharing feature of iTunes, copy the GridA3.pkg file to iDraw. While still in iTunes, rename the file GridA3.idraw. Close and re-open iDraw and you will see the new file. Duplicate that document to have the scaled five line grid system and the pre-defined layers.
As you draw, you will often see a rectangle with the dimensions of the object near your finger. If you are used to doing scaled drawings at all it will soon become easy to translate those cm dimensions on the screen to cm dimensions on the ground. Multiply the number on the screen by 20 to get the ground measurement. This allows you to draw triangulation lines corresponding to tape measurements to properly place objects.
A bonus to using the A3 sized document to practice with is that you can import the drawings from the previous exercises and, since they were scanned at 100% scale, they will be properly scaled on the iDraw drawing.
Here are a couple of finished drawings from the 2009 season of PARP:PS:
Paperless Archaeology 