Architectural_Design_with_SketchUp

Chapter 6 Creating Geometry Using Ruby Scripting
axis (the green axis), and a third for the z axis (the blue axis). We will also use the pushpull
method of the Face object to extrude the faces into boxes.
Paste the following code into the Ruby Code Editor in SketchUp and click on Run Code:
# Creates a 3D grid of similar boxes
ent = Sketchup.active_model.entities
n = 5 # number of boxes
s = 100 # spacing
w = 20 # width
(0..n-1).each { |i|
(0..n-1).each { |j|
(0..n-1).each { |k|
# add a face first
face = ent.add_face [i*s,j*s,k*s],[i*s,j*s+w,k*s],[i*s+w,j*s+w,k*s],
[i*s+w,j*s,k*s]
# then pushpull it to get a box
face.pushpull -w
}
}
}
The result will look like Figure 6.8.
As this demonstrates, creating extruded geometry
is very easy. First, we needed to create a face. This
was done using the add_face method. As always, the
face was simply added to the Entities collection.
Instead of just adding it, though, we assigned
it at the same time to the variable face. This gave
us a way to apply the pushpull method to the face
and extrude it by a given amount w.
You might have noticed that w is entered as a negative
number (there is a minus sign in front of it). This
is because whenever you create a face in SketchUp,
the white side of the face (the “front”) points downward.
A positive w would have extruded it downward
as well. Because we want to extrude it upward, w
must be negative (or you would have needed to first
flip the face’s orientation using its reverse! method).
Of course, you have to be careful with this script.
As you can imagine, changing a single number (n)
significantly impacts the amount of geometry created.
After all, each cube consists of 18 elements:
6 faces and 12 edges. Figure 6.8: 125 boxes created quickly by a script
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