Referenced Viewport on a Site Plan Question.

MaltbyDesign · March 9, 2021

I created a site plan model (digital terrain model) and inserted my building model as a Referenced Viewport. My first problem was the building model disappearing and I discovered that I needed to increase the crop area of the viewport so as not to crop the model itself, depending on the view. Fair enough. However if I switch to a front, right, left or back view, the building model disappears and the crop outline is far removed from the site plan (back down to z=0, despite adjusting the building models z-value to bring it up to the same elevations at the site topography (which was created using real elevations so the site plan is 690' above zero. What's causing this and how do I fix it?

The next hurdle is that I now see that if I use the clip cube command through the site plane, the site model gets clipped while the building model doesn't. A section viewport does create a section of both the site and the building model reference, so that's a plus. I'm assuming I'll be able to modify the site model with the building model as a referenced viewport in order to remove the earth from the basement, so to speak.

I tried this method as I saw it mentioned in various posts about adding buildings to site models. But is it the best way for small, simple projects? Am I better off drawing the building and the site model in the same drawing file and adjusting my main floor elevation to the correct geodetic height?

Jesse Cogswell · March 10, 2021

The problem that you are running into with the Reference Viewport crop object is that VW treats it as a screen object, so it doesn't respect the 3D views you are trying to put it in. The easiest way to see this is to switch to the flyover camera with the Referenced Viewport selected or with "Crop Visible" checked. As you move the camera around, you'll see the model disappear when it's outside of the screen-locked crop object.

I've never found a good solution to this outside of not cropping and Referenced Viewport that I need the 3D model for. The other thing you could try is setting the things you do not need to see in your building model file to be on a separate layer that you can toggle off, eliminating the need for a crop.

Once you remove the crop, try the Clip Cube again. I use the Clip Cube with Referenced Viewports all the time and never had any major problem with them outside of some weird rendering problems when using Renderworks, but that's a bug with the Clip Cube and not Referenced Viewports.

Jeff Prince · March 10, 2021

@MaltbyDesign Here's my process

building in its own file (ff of ground floor = 0). If there are multiple buildings, each in its own building file.

Site in it's own file (elevation based on real world)

Reference the building(s) into the site file. Move the reference(s) such that ff of the building(s) sits on the desired elevation of your model.

Clip Cube and sections with ease.

Some examples at the extreme ends of complexity I have developed....

Simple house on a simple site, though there is a walkout basement with retaining modifiers at work.

vs

1km long coastal development with 23 buildings of various levels of detail referenced including a drone based phototextured topo model, roughly 4GB of data in total.

The clip cube spins and cuts in real time without delay. Section viewports can take a little while to generate.

Same approach used, same results, this running on a 2015 Macbook pro even. Admittedly, things were slower in 2019, but 2020 is hot knife thru butter on this stuff.

Hope it helps.