Question

SURFACEDRAPER

  • 23 August 2013
  • 4 replies
  • 11 views

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Hi there,

 

I have aproblem with the "surfacedraper" transformer. I want to create the projection of a polygon feature that represent the ground surface of a building, on another polygon that represents the roof, in order to create the walls. The groun surface is smaller then the roof surface, so  have to create this projection that coresponds to the fingerprint of the actual building, and then substaracted from the original roof to get the eaves of the house.

 

 

I've tried to use surfacedraper by tranforming the vertices of the ground polygons in to points and projecting them on the roof, but i get some points with elevation =1 and i don't know why?

 

I gues that a posible cause might be the fact that there are more then one point in the same location that need to be projected(in the case of buildings that have the same roof and separate ground suface that have a common edge)

 

Any ideeas?

 

Any other ideeas to get my polygons are welcome?

 


4 replies

Userlevel 4
Badge +13
Hi,

 

How about extruding the roof toward the ground?? Just an idea...
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I don't have the projected roofs in order to project them towards the ground. This is what i'm traing to get here....

 

Badge +3
seems like u have to scale a flat projection of your roof to fit inside your groundsurface flat projection.

 

Assuming the groundsurface is to extent of your buildingfootprint.

 

Else u need to now the size/overhang of the eaves to do it.

 

And if u did latter and it would'nt fit, you'ld need to extrapolate the groundsurface or acquire more of it.
Badge +3
ditch the y-values to do the porjection.

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