Engineering for Ruby

This is a meta-gem for all things related to engineering (particularly CAD stuff). The Engineering module is your one stop shop for all of the tools you need for your latest mad-engineering project.

Activating a dormant volcano? Adding death rays to your secret moon base? Plotting world domination? No problem! There's a gem for that, and you've found it right here.

If your latest and greatest project, and even your older ones, need something that isn't in Engineering, either let me know, or fork and add it yourself (and send me a pull request). Or feel free to create your own gem that reopens the module and adds whatever is missing, if that's more your style.

License

Dependencies

DXF GitHub RubyGems
Units GitHub
Geometry GitHub RubyGems
Sketch GitHub
Model GitHub

Installation

Engineering has a number of dependencies. Some of which are hosted on rubygems.org and can therefore be handled by the gem utility, but others must be installed manually. The easiest option is to use Bundler, but gem can be used if you're willing to install the units gem manually.

Using Bundler

Installing the engineering gem using bundler is very easy, although a little more involved than normal.

Start with the normal gem command:

gem install engineering

Unfortunately, this will either fail, or it will grab the wrong version of the units gem. But, not to worry, we can use bundler to fix it:

bundle install

And that's it. You're done. Get on with taking over the world already.

If you happen to be part of the 0.001% of Mad Engineers who don't already have bundler installed, it's very easy to get:

gem install bundler

Using Rubygems

Sadly, the units gem hosted on Rubygems is a bit out-of-date, and generally not the gem we're looking for. So, after gem does its thing, we need to do a little cleanup.

Start with the normal gem command:

gem install engineering

Then uninstall the bogus units gem:

gem uninstall units

Clone the gem we're looking for:

git clone git://github.com/bfoz/units.git

Install it:

cd units && rake install

You do have rake installed, right? If not, do this before the previous step:

gem install rake

And you should be good to go. If you made it through all of that, then I expect to hear about your machinations on the evening news any day now.

Examples

Creating a custom Cube class, the hard way:

require 'engineering'

model :MyCube do
    extrusion 10.cm do
        square 10.cm
    end
end

MyCube.new

Of course, this is ruby, so there's always another way to do it

extrusion :MyCube do
    rectangle Size[10.cm, 10.cm]
end

MyCube.new length:10.cm

Exporting

Once a Model has been defined, it can be instantiated and exported to SketchUp with a single line

SketchUp.write('MyCube.su', MyCube.new)

Then, launch SketchUp, open the Ruby Console (it's in the Window menu), and load 'MyCube.su'. Your new geometry will replace whatever was already in the SketchUp document (a person if you just opened it), so be careful.