Architectural_Design_with_SketchUp

Architectural Design with SketchUp
styles, tools, etc., collections). Once we get hold of the entities collection, we can add a
face using the add_face method.
The add_face method, in turn, accepts 3D points as arguments; because this face is a
triangle, we need to supply three points. These points, in turn, are sufficiently defined by
an x,y,z coordinate, which we are supplying as a three-member array ([0,0,0] is the point
definition for the origin, of course). This is a triplet coordinate array, which corresponds to the
location based on the x (red axis), y (green axis), and z (blue axis) coordinates, respectively.
TIP
When you look deeper into Ruby, you will learn that what I call an object is often called
a class. I do this to (hopefully) reduce confusion. Technically, methods and the like are
defined in a class in Ruby, which then is instantiated as an object when you use it.
When you start up the Ruby Code Editor in SketchUp (installed using the plugin, as
described earlier in this chapter), you see that a few shortcuts are already preprogrammed:
mod = Sketchup.active_model # Open model
ent = mod.entities # All entities in model
sel = mod.selection # Current selection
This makes it easy to work with some of the basic collections. With these three lines at the
beginning of our code, we can now simply add a fourth line to accomplish what we did before:
ent.add_face [0,0,0],[0,10,0],[0,10,10]
If you have selected any objects in your current model, you could simply access the first
selected object using sel[0], for example, to move or copy it.
Instead of going through the list of available objects and methods, the next sections show
you an overview diagram and explore some of the functionality using code examples. To serve
you as a reference, the complete API object and methods listing is included in Appendix C.
Object Reference Diagram
The makers of SketchUp have produced a useful diagram, shown in Figure 6.7, that explains
visually the object (or class) hierarchy. Please note that the following are not included in this
diagram:
Core Ruby Classes: Array, Length, Numeric, String; UI Classes: Command, InputPoint,
PickHelper, Menu, Toolbar, WebDialog; Geom Classes: BoundingBox, LatLong, Point3d,
PolygonMesh, Transformation, Vector3d, Vertex; App Level Classes: Animation, Color,
Extension, Importer, Options Manager, Options Provider, Set, TextureWriter, UVHelper;
Observers: OptionsProviderObserver.
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