Architectural_Design_with_SketchUp

Chapter 6 Creating Geometry Using Ruby Scripting
Feel free to experiment with different components using this code. You can even place
ones that have thickness (e.g., a cylinder) using this method.
Randomizing Everything
In the following code, we revisit the use of random numbers and combine this with what we
learned about transformations. Specifically, we take the selected objects (all must be component
instances) and apply a random rotation as well as random scaling to each. Before
you run this code, add some components to your model—trees or other shrubbery make for
great examples. Just make sure you are not using face-me components.
# Apply randomized rotation and scaling to selection
mod = Sketchup.active_model # Open model
ent = mod.entities # All entities in model
sel = mod.selection # Current selection
max_rotation_angle = 90
size_var = 0.5 # Keep below 1
sel.each { |e|
if e.typename == ”ComponentInstance”
# Get the center of the selected object
center = e.bounds.center
# Also get the base center for scaling
base = center.clone
z_height = (e.bounds.max.z—e.bounds.min.z)
base.z = base.z—z_height/2
# Transform this object
t1 = Geom::Transformation.rotation(center, [0,0,1],
(rand * max_rotation_angle).degrees)
t2 = Geom::Transformation.scaling base,
1—size_var/2 + rand*size_var
# Combine transformations
t = t1 * t2
e.transform! t
end
}
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