revising topo to site model

[hong]

I am wondering how to manuplate existing topo lines in order to generate a proposed site model. Even though VW provides site modifier to regrade existing, there are times when we have to do it manually. If this is the case, where should I do this?

I now have a layer with 3d ploygon data for existing site and a layer where the generated site model resides. It seems that I have to create another layer where existing 3d polygon data are copied and altered in addition to site modifier and create a proposed site model from it. Is this a correct?

[Robert Anderson]

Well, I can't stop you if you want to do it the hard way. Here's how to do what you want:

1. Create an open pad modifier for each topo line within the area of the site that you want to manually modify. Just trace over the topo lines you want to change with the Site Modifier tool set to "Pad". Set the elevation of the "pad" (break line, actually) to the elevation of the topo line.

2. Draw a fence modifier around the collection of pad modifiers.

3. Reshape the pads to the shape of the new topo lines you want.

4. Recalcuate the site model.

[hong]

Thanks for your reply.

Is there a reason to insist on using site modifier instead of copying and altering topos then create a model from it?

[Robert Anderson]

If you want to do that, you can, but you must do so in a separate document. Each site model would be an "existing" site model in our data structure, and each file can have only one such.