topic How can i Get block center value in ArcGIS CityEngine Questions

How can i Get block center value

JeoCho — Thu, 10 Nov 2022 09:52:58 GMT

I have many blocks

In each blocks , i would like to get center corrdinate x z

How can i that ?

Re: How can i Get block center value

plfontes — Thu, 10 Nov 2022 15:15:41 GMT

Hi JeoCho,

If your intent is only to know the centre points, you can run the following python script on any selected block:

''' Created on 10 Nov 2022 @author: Plfontes ''' from scripting import * # get a CityEngine instance ce = CE() @noUIupdate def getBlockCentroid(): # get selected blocks blocks = ce.getObjectsFrom(ce.selection(),ce.isBlock) for block in blocks: # get/print centroid print(ce.getOID(block), ce.getPosition(block)) if __name__ == '__main__': getBlockCentroid()

This will print to the console the block ID and its centroid (x, y, z) position.

Hope this helps.

Re: How can i Get block center value

JeoCho — Thu, 10 Nov 2022 16:17:00 GMT

Really thank you for reply

really sorry ,I have a other question

Example)

I would like to make this cga , but your code is python

If i have 3 block a , b ,c

Dist = The value of distance between a block center and lot

if dist < 1000 -> high building

If dist > 1000 -> residental house

I make this process

How can i make in cga?

Re: How can i Get block center value

CherylLau — Wed, 14 Dec 2022 14:22:11 GMT

I assume you are working with dynamic shapes, meaning blocks and lots that are automatically created by CityEngine in a street network. I assume you want CityEngine to automatically divide the blocks into lots. In this case, unfortunately, I can't think of a way in cga for each Lot to know the centroid or any information about the block it belongs to.

The only way I can think of is to start with the dynamically created blocks, do not subdivide them automatically (select blocks, set Subdivision Type = "No Subdivision" in Inspector), and subdivide them in your cga rule instead. Here is some code that calculates the block's centroid, places an invisible cube at the centroid, and subdivides the block into lots. Each lot queries its minimumDistance to the invisible cube at the centroid. If you don't need the exact centroid, it would be simpler to skip the centroid calculation and center the invisible cube in the block's scope instead. You can replace the SubdivideIntoLots rule with any algorithm you prefer. I know it's not ideal, but maybe this gives you some ideas of how to proceed.

const numBlockVertices = geometry.nVertices const sumOfBlockVertices = [ sum(comp(v) { all: convert(x, scope, world, pos, 0, 0, 0) }), sum(comp(v) { all: convert(y, scope, world, pos, 0, 0, 0) }), sum(comp(v) { all: convert(z, scope, world, pos, 0, 0, 0) }) ] const centroidInWorld = sumOfBlockVertices./numBlockVertices const cubeWidth = 1 const blockCentroidLabel = "BlockCentroid" const splitDist = 30 const tallBuildingThres = 10 Block --> BlockCenter SubdivideIntoLots BlockCenter with( centroidInScope := convert(world, scope, pos, centroidInWorld) ) --> primitiveCube s(cubeWidth, cubeWidth, cubeWidth) t(centroidInScope[0]-0.5*cubeWidth, centroidInScope[1]-0.5*cubeWidth, centroidInScope[2]-0.5*cubeWidth) label(blockCentroidLabel) NIL SubdivideIntoLots --> splitAndSetbackPerimeter(0) { splitDist: splitDist: Lot }* { remainder: SubdivideIntoLots } Lot with( distToCentroid := minimumDistance(intra, blockCentroidLabel) ) --> case distToCentroid < tallBuildingThres: TallBuilding else: House

Re: How can i Get block center value

JeoCho — Thu, 15 Dec 2022 05:20:33 GMT

Thank you

This is what i was looking for

Really really thank you