topic How to create a rule for placing trees using points.shp? in ArcGIS CityEngine Questions

How to create a rule for placing trees using points.shp?

aTomasaLooström — Tue, 28 Oct 2014 14:03:41 GMT

Hi,

I haveshape points with type and height for individual trees.

I would like to know how to write a rule that I can use to place the .obj models using
the attributes from the shape-file. The points are loaded in CE at their right
locations.

I manage to
get the right height and rotate them use this rule from the forum, but I get
Unknown Texture… The mtl is in the assets folder.

attr Hojd = 0

attr TREETYPE = "Witch_Hazel_Model_0"

cowTex = ("assets/Trad/Witch_Hazel_Model.mtl")

getAssetPath = ( "assets/Trad/" + TREETYPE + "/Witch_Hazel_Model_0.obj" )

@StartRule

TREE -->

alignScopeToAxes(y)

s(0,Hojd,0) center(xz)

r(0,rand(360),0)

i(getAssetPath)

texture(cowTex)

Tree.

Best regards Tomas

Re: How to create a rule for placing trees using points.shp?

Anonymous User — Tue, 28 Oct 2014 14:36:11 GMT

First, omit the line "texture(cowTex)", since the model should have textures applied - the i() operation is all you need to get the textures.

Next, make sure the file "Witch_Hazel_Model.mtl" is in the same folder as the "Witch_Hazel_Model_0.obj"

This brings up another possible problem. I notice your OBJ file is "Witch_Hazel_Model_0.obj", but the texture file does not have"_0.mtl" at the end. That may or may not indicate a problem. Open the OBJ file in a text editor, and search for the string "Witch_Hazel_Model" (a few searches until you find reference to the ".mtl" material file). Does it say "_0.mtl" or just ".mtl" at the end? What needs to happen is that the OBJ file must find its texture file. I'm seeing a possible path problem, and a possible naming problem here. Try those and let me know.

Chris

Re: How to create a rule for placing trees using points.shp?

aTomasaLooström — Wed, 29 Oct 2014 12:39:11 GMT

Tanks for quick respons:)

I am new to programming, learning by the CE tutorials and at the same time building developments models at the goverment at Gotland, Sweden...

I found this rule that I manage to change it and to work as well:

attr TRAD = ("assets/Trad2/Witch_Hazel_Model_0.obj")

attr Hojd = 0

@StartRule

Point -->

alignScopeToAxes(y)

s(0,Hojd,0) center(xz)

r(0,rand(360),0)

i(TRAD)

/Tomas