Architectural_Design_with_SketchUp

Chapter 6 Creating Geometry Using Ruby Scripting
}
}
}
transformation = Geom::Transformation.new([i*s,j*s,k*s])
ent.add_instance(comp.definition, transformation)
As you can see, this code creates a grid of boxes similar to Figure 6.8. In contrast to
what we did before, this time we created one box that has the appropriate geometry. Then
we changed it into a component using the group.to_component method. It is only after this
that we loop through the locations, define an insertion point using a transformation, and
add a component instance (as comp.definition) using the add_instance method at that
insertion point.
Building a Curved Wall
Let’s expand a bit on the previous code. In this snippet, we’ll take a preexisting component—
a 1f × 1f × 2f block in the example used here—and place it multiple times while rotating it.
The rotation is again guided by a combination of sine and cosine in the horizontal and vertical
directions.
To use this code, you must first have a component instance in your model (the block you
see in Figure 6.17 is the one used here; place it anywhere you like). Before you run the code,
make sure you select the component—otherwise, nothing happens.
# Rotate-copy placement of a component
mod = Sketchup.active_model # Open model
ent = mod.entities # All entities in model
sel = mod.selection # Current selection
s = 28 # x-spacing
t = 12 # z-spacing
h = 20 # number in x
v = 20 # number in z
max_deg = 90 # Max ”opening” angle
if (sel[0].typename == ’ComponentInstance’)
v.times { |j|
h.times { |i|
# Place a brick at the specified location
t1 = Geom::Transformation.translation([i*s,0,j*t])
instance = ent.add_instance(sel[0].definition, t1)
# Calculate angle and rotate the brick vertically
angle = (sin((i*180/h).degrees)+sin((j*360/v).degrees))*max_deg/2
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