mat,
Let�??s make 20~30 trees with the field �??Height�?? (from 5 to 15 m) as an example, in a point feature class; and then,
In ArcScene:
Step 1: load /configure the point feature class in ArcScene;
Step 2: symbolize those points with 3D tree (saying, American Sweet Gum);
Step 3: Configure the �??Advanced�?? under the Tab �??Symbology�??, which use the tree height as Size and pick Rotation Angle as Random. In this way, the 3D trees in ArcScene will be well presented and also very light (excellent performance, compared to similar approach in CE.)
Step 3: export 3D trees with model into multipatch (GDB);
Step 4: load into CE. (Those 3D trees should look same as in ArcScene. Unfortunately, those 3D trees model is changed, i.e., not properly rotated in CE. (See the snapshot above.)
In CE:
Inversely, if producing 3D trees in CE from point feature class by �??vegetation.cga�?? and then exporting into 3D trees feature class (GDB), ArcScene will change the model of those 3D trees as well, so that the 3D trees presented/rotated not properly (i.e., same as the snapshot above.)
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It looks that it is an interoperation issue between ArcScene 10.1/10.0 and CE 2012.1, when dealing with 3D multipatch with models (tree, street furniture ...) , which is derived from �??point�?? feature classes.
Not sure if it is a 'known' issue to 3D/CityEngine team�?�
Regards,