ce_unexpected_consequences
Bridge Supports don’t go upwards…. (generally)

Did I tell you I like CityEngine today?   Okay you will have noticed that CityEngine gives a designer an instant feedback on their rule files.   You move a centre line of a road or a node on a building plot and the model created on top of it dynamically changes as it’s moved.    It’s fascinating to watch your simple rule files come alive.

Take this example, it’s my attempt at really simplifying a street rule that includes a bridge element.  Above a certain elevation (either 0 or a terrain) and the street gets bridge supports and simple sides.   Also no trees are planted and no zebra crossings (‘crosswalks’ to our North American friends) are created either.

It works great, raise the road and supports are made, trees are taken out, just as I wanted but what happens if the road goes down… well have a look, I think I have some unintended consequences of a decision I made in my rule file…

You see?  I’ve created a model from a rule and can instantly see that I have made a mistake.  Or perhaps better described I need to modify this rule to be more forgiving of the terrain.   Perhaps when the road is below ground I should put a tunnel around it?   Come to think of it I’ll go and do that now…