nav[aria-label="Primary Navigation"] { padding: 0; & ul { list-style: none; width: 100%; display: flex; flex-direction: row; justify-content: start; align-items: start; gap: 30px; padding: 0; & li { margin: 0; } & ul li { list-style: none; } } }

How to apply different rates of change to different parts of the building?

TianfangJiang

Hi guys,

The grids in the following picture is the .shp file which is exported from ArcGIS. Then I read the MEAN_Z attribute from the Object Attribute and attributed it to the following grids.

After that I obtained the building in the following picture. Now my work is to modify this building. First I want to change the heights of different parts of the building. My problem is how to apply different rates of change to different parts of the building.

I tried to write the code like this: attr MEAN_Z

attr height= MEAN_Z*0.5;

but the result is the height of the whole building became 0.5 times than before which is not what I need.

How can I divide this building into different parts based on so many grids and how can I apply different rates of change to different parts?

I think you guys are more professional than me and thank you for your help

Encontre mais publicações marcadas com

Accepted answers

CherylLau

Ok, so I was under the assumption that you had one shape with multiple faces. In this case, the split operation would work, but if you had multiple initial shapes, there's no way to combine them in the rules. I would suggest combining all the shapes into a single shape either in CE or in the software you are using to generate the shapefile.

You could combine all the shapes into one shape in CityEngine by selecting them -> Shapes -> Combine Shapes. This will give you a single shape with multiple faces. Then you can apply a rule to the single shape.

Or, you could combine all the shapes into a single shape before you export your shapefile. It should be a similar procedure as in CityEngine (select all the polygons, then find the menu item to combine the polygons).

All comments

CherylLau

You could apply a component split to get all the faces of your object and then apply a rule to each face. The rule could set the height of building. (For the following code, assign the start rule Lot to your initial shape.)

Lot -->

comp(f) { all : Face }

Face -->

extrude(rand()*20 + 0.5*MEAN_Z) // set height to random value in [MEAN_Z - 10, MEAN_Z + 10]

CodyBenkelman_6-1715373523023.png

TianfangJiang

Thank you Cheryl, but I don't want to set the height of building in a random value, I want to set it as a specific value which I need. And do you know how to divide the building into several parts?

Thank you for your help.

CherylLau

You can set the building height to whatever you want. I just chose random heights as an example, but you can put in your own calculations.

If you want to divide something into parts, then you'll probably want to use the split() operation:

split Operation

Or, if you want to separate out the individual faces, then you'll probably want to use the comp() operation:

Component Split Operation

TianfangJiang

Thank you Cheryl, I think you are right, maybe I need to use the Split Operation, and then attribute different heights to different parts.

TianfangJiang

Hi Cheryl,

I tried to apply the Split Operation but the result is that the separation can only be applied on each grid instead of the whole building geometry. The follow picture shows the result,

The code I write for the separation is: split(x) {'0.5:Z|

'0.2:Y|

'0.3:X}

What should I do if I don't want to split each grid but to group these grids into several parts?

Thanks!

Participe da Conversa

Membros conectados podem postar, seguir atualizações e mais. Novo aqui? Registre uma conta gratuita.

Entrar
Registrar

Links Rápidos

Community Help
Find useful guides, FAQs, and documents to help you navigate and make the most of Esri Community.