# Thread: Rules for distance of parcel limit at Building

1. ## Rules for distance of parcel limit at Building

Hello

I'm working on a urban model derived from the town planning regulations.
I required to establish differential distances between the boundary of parcel and the limit of each side of the building
I tested with the offset command but applies the same distance from all faces, but I need to differentiate between the face and apply a distance

What command should I use, or what is the proper rule?
There is some learning resource CityEngine in Spanish, or any forum in this language?

I appreciate any help. Thanks.

2. ## Re: Rules for distance of parcel limit at Building

You can use the setback operation, in a recursive manner.

I think any solution depends on some more details of your problem...
The solution I provide bellow does not seem very elegant, nor it works in every situation... but it might get you going for now...

Code:
```version "2011.2"

attr buildingHeight = 10

attr buildingColor = "#4A708B"

attr leftColor = "#FF0000"
attr rightColor = "#0000FF"
attr backColor = "#FFA500"
attr frontColor = "#800080"

attr frontSetback = 2
attr leftSetback = 8
attr rightSetback = 4
attr backSetback = 10

@StartRule
LotInner -->
NIL.

@StartRule
LotCorner -->
NIL.

@StartRule
Lot -->
setback(frontSetback){
front: color(frontColor) FrontPart.|
remainder: MinusFront
}

MinusFront -->
setback(leftSetback){
left: color(leftColor) LeftPart.|
remainder: MinusFrontAndLeft
}
MinusFrontAndLeft -->
setback(rightSetback){
right: color(rightColor) RightPart.|
remainder: MinusFrontLeftAndRight
}

MinusFrontLeftAndRight -->
setback(backSetback){
back: color(backColor) BackPart.|
remainder: MinusFrontLeftRightAndBack
}

MinusFrontLeftRightAndBack -->
Mass

Mass -->
alignScopeToAxes(y)
extrude(world.y, buildingHeight)
color(buildingColor)
Mass.```
I don't know any documentation in spanish though :S
I normally use the application help menu window, and this forum

Hope it helps!!

3. ## Re: Rules for distance of parcel limit at Building

Thanks, i'll try to base me in your solution and then i comment the results.