Architectural_Design_with_SketchUp

Architectural Design with SketchUp
As you can see in Figure 6.21, this little snippet can add quite a bit of realism, especially
to natural objects like trees.
Figure 6.21: Randomized rotation and scaling (left: before; right: after)
To create this effect, the code first takes the entire Selection collection and iterates through
each element using sel.each. It then checks that the current element is a ComponentInstance.
You could apply this to all kinds of entities; however, transform! is a method that works only
for the ComponentInstance object. You would have to modify the transformation slightly
for other objects.
Next, the code finds the center of the bounding box of the component as well as the
center of its base. To find the base center, we needed to calculate the height of the box and
then subtract half the height from the z value.
Finally, we define two transformations, one for rotation and one for scaling, and combine
them by multiplication. As you can see in the code, two variables allow you to modify the
maximum rotation angle as well as the maximum size variation (as a ratio). Experiment with
these values until you get the results you are after.
Attracted to Attractors
The following examples show how you can modify geometry based on proximity to some
other object (or any relationship you can think of, such as “height from ground”). This often
yields very interesting designs and lets you express relationships visually in your designs.
At the minimum, what is required to make these examples work is (1) some geometry
that you intend to modify and (2) one or more objects that act as attractors, on which the
modification is based. A good example of the first is a facade panel whose color or shape
you intend to modify. It doesn’t have to be a face, though—you could instead use a group
or a component instance.
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