First some Vocabulary...
Ruby Command = a line of text that tells SketchUp to "do something"
Ruby Console = a window inside SU to enter Ruby Commands. Window > Ruby Console
Examples: copy and paste each of these into your Ruby Console and hit "enter"
UI.beep
UI.messagebox("Hello!")
answer = (10 * 4) + 2
UI.messagebox(answer)
UI.menu('PlugIns').add_item('Beep!') { UI.beep }
Variable = a named "value" in programming. In the example above, answer is a variable
Plugin = one or more text files that contain ruby commands that run at startup
Plugin Folder = A "magic folder" on your machine where Plugins are loaded from
PC: ProgramFiles (x86)\Google\Google SketchUp 8\plugins
Mac: Library/Application Support/Sketchup 8/Plugins and/or
~/Library/Application Support/Sketchup 8/Plugins
Extension = a special kind of plugin that can be turned off in the Preferences > Extensions dialog
Text Editor = a text editing program that saves "raw text". notepad.exe on PC, textedit on Mac are fine.
Be sure you're saving as raw text, not RTF!
.rb = A ruby file. It's just a text file with a .rb file extension
.rbz = A zipped ruby file. This is a zip archive with one or more .rb files in it. Easy to install.
.rbs = A scrambled ruby file. (Scrambled ruby via the scrambler to keep your code "secret")
Tool = at any given time, one tool is active in SketchUp
Edges and Faces = SketchUp's basic geometry. Learn to draw these, you can draw anything!
Component Definition and Instance = Definitions contains Faces/Edges, Instances are the copies
Group, Material, etc. = Most of what you know from SketchUp can be manipulated in the API
x / y / z = 3 numbers represent location in 3D. In Ruby, these are always inches.
Ruby API vs. SDK = Application Programming Interface vs Software Development Kit
Okay, let's get coding...
1. If on a PC, modify the SketchUp 8 folder to have write permissions!
You may need to do this on a mac as well... we can help.
2. Bookmark the documentation developers.google.com/sketchup
Quick Reference -> Classes
Quick Reference -> Methods
If you want, grab the dev tools beta for a better Ruby Console.
3. What kind of learner are you?
Like an overview first? Check out this Ruby Cheat sheet
Want to learn Ruby itself? Try http://www.codecademy.com/tracks/ruby
Do you learn by doing? Jump into Lesson 1 and keep going.
Do you learn by real world examples, jump to Lesson N to get some code