Discover how to add and manage four different types of boundaries within a surface using Civil 3D, a design software that offers flexible, dynamic modeling capabilities. This detailed guide showcases the nuances of outer, hide, show, and data clip boundaries, and demonstrates how to leverage each one effectively within your surface model.
Key Insights
- There are four types of boundaries you can add to a surface in Civil 3D: outer, hide, show, and data clip. Each serves a unique function in defining the display and calculation of surface data. Outer boundaries limit data display to within the boundary, hide boundaries conceal data within the boundary, show boundaries reveal data within a hidden area, and data clip boundaries restrict the calculation of surface data to within the boundary.
- Boundary types in Civil 3D are non-destructive and do not remove data from your surface. Even when data is not displayed due to a boundary, it is still calculated and controlled by surface definitions and used within the drawing. This is different for data clip boundaries, which remove any data outside of the boundary from surface calculations.
- Adding a data clip boundary requires additional steps. After adding this boundary type, you must promote it to the top of your surface definitions for it to correctly clip data. It's important to note that this boundary doesn't automatically update the surface; the surface must be rebuilt after adding a data clip boundary.
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In this video, we're going to talk about the four different types of boundaries that you could add into a surface. We're going to be adding these boundaries to our surface that we've been working with in the entire drawing.
Between the last video and this video, what I went ahead and did is I went and deleted the surfaces that we had created in the previous video. If you want to go ahead and do that, if you were following me along, what you can do is you can navigate to the tool space, prospector tab, go to your surfaces dropdown and expand, go to your surfaces that we created in the previous video, select any of them, right click and choose delete. So what you want to be cognizant of is that if you're deleting surfaces, you want to make sure you delete surfaces that are referencing other surfaces first, and then delete the reference surfaces next.
So in our case, we would be deleting the combo surface first, and then you could delete the large and small surface. We're going to be working with this surface that we have here that has our street and our parcels, and we're going to be creating four different kinds of boundaries. So I'm going to go ahead and draw four different rectangles.
So I'm going to start by doing a rectangle that starts somewhere inside property two and goes all the way over to the bottom corner of our surface down here. Now I'm going to go ahead and draw another rectangle that starts somewhere inside property three in the bottom left corner, and I'm going to drag it all the way down to somewhere on the other side of the street, but not down into the slope. Then I'm going to draw another rectangle starting in property eight, expanding downwards, and going to the other corner of property eight.
I'm going to add my last rectangle as an interior rectangle to that third rectangle that we drew. So what I'm going to be doing is I'm going to be using the outer boundary that we drew here as a data clip boundary. I'm going to be drawing this interior second boundary as our outer boundary.
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Then I'm going to be displaying the third boundary as a hide and the fourth boundary as a show. So I'm going to first go through the easier ones to understand, which is outer, hide, and show, and then I will show you the difference that there is between a data clip and the other three. So what we're going to go ahead and do is we're going to go to full development.
We're going to expand it down, go to definitions, expand it down, go to boundaries, and right click. I'm going to select add, and when I go to add, I'm going to drop down my type and select outer. I'm going to choose the name of outer as my boundary.
I'm going to check for a non-destructive break line so that Civil 3D adds in a non-destructive break line into my surface as the outer boundary that I'm creating right now. So I'm going to go ahead and click okay, and I'm going to choose the second boundary that we created, which is this one right here. I'm going to click it, and what you'll notice is Civil 3D now does not show any data outside of that boundary.
So that's okay because later we'll come back and deal with this data clip one that's hiding on the outside or that's being shown on the outside here. So from there, we're going to move inside. We're going to go back into boundaries, right click, select add, drop down, choose hide, type in the name of hide, and then I'm going to click okay.
I left the check mark on for non-destructive break line because I want Civil 3D to add a non-destructive break line as my boundary. So I'm going to click and hit ENTER, and so what Civil 3D does is it hides the information from the rest of the surface. So from here, I'm going to go back into boundaries, right click, select add.
I'm going to type in show. I'm going to drop down the type, select show, leave non-destructive break lines checked, and since I don't have any curves, I'm not specifying any of the mid-order distances for any of these boundaries. So I'm going to go ahead and click okay.
I'm going to select the interior boundary and hit ENTER, and so what you'll see here is that if I select my surface and I go to object viewer and I bring my object viewer window over here, expand it, and rotate into three-dimensional view, what you're going to see is I have a surface that has a boundary that defines where to show data. It says do not show any data past this line here. This is the outer boundary.
Then we have a boundary here that is a high boundary, and it basically says do not show any information inside of this boundary. This is hidden from the surface, and then it has a third boundary that is the show boundary, and it says I'm currently residing inside of a hidden boundary. Please show all the data inside of this boundary.
So that's how a outer hide and show boundary work. Now the interesting thing to note about any of these boundaries is that they are non-destructive. They are not removing data from your surface.
So all of the data for all the points outside of our surface are still being calculated and controlled by our surface definitions and are still being used inside of our drawing. Now with a data clip, that's completely different, and it actually works differently than any surface that we've seen or any boundary that we've seen before. So with these boundaries, if we go to the full development, right-click and go to surface properties and go to our definition tab, what you'll notice is that these boundaries were added at the bottom.
So what I'm going to go ahead and do is I'm going to remove my outer boundary, and then I'm going to leave my hide and show. So I'm going to go ahead and click OK. I'm going to click on boundaries.
If you want to remove it, you can go ahead and click outer, right-click, and select delete. Civil 3D is going to tell me, do you want to remove this definition from your surface? I'm going to say OK, and then I'm going to rebuild my surface by selecting my surface, choosing rebuild. So my surface has now been rebuilt.
I still have my hide and show boundaries in here, and I'm going to go ahead and go back into boundaries, right-click, select add, and I'm going to drop down and select data clip. Now what you're going to notice when you have data clip selected is that you cannot check non-
Destructive breakline. That's because this boundary is going to be used as a clip for any data showing up outside of it, but it does not want to add data to the surface.
We're going to go ahead and type this as data clip. I'm going to go ahead and select OK, and I am going to select my outer boundary, and what you'll notice is Civil 3D did not automatically update the surface, and that is because a data clip has to be oriented first. It needs to tell the surface first what data has been removed, because if this comes afterwards, all the data that came before it is still being drawn into the surface.
So what you have to do when you add a data clip boundary in is that you have to go to full development or whatever surface you're working with, select surface properties, go to your definitions, find your data clip, and promote it all the way to the top. So it needs to be the first item that the surface sees to correctly do a data clip. So I'm going to go ahead and hit apply, rebuild the surface, and click OK.
And so what you're going to notice here is that the boundary for the surface does not reside on the data clip boundary. The boundary of the surface is defined by the data that is still currently being used in your surface calculations. All of the data outside of this boundary is not being used.
Any of the data inside is being used currently. So you can go ahead and still have your hide boundary, your show boundary. I didn't have to delete my outer boundary.
I could have gone ahead and had this here and done a data clip, but the reason why I removed the outer boundary is so that you could see how this data clip boundary has a definition that keeps the points that are interior, removes the points that are exterior, removes any data that's coming in from the outside of that boundary. So from here, I'm going to go ahead and actually delete all these boundaries because I don't want to keep them in my drawing. So I'm going to go ahead and minimize, or I'm going to click on full development, click on boundaries.
I'm going to go ahead and select data clip, right click, delete, select OK, select hide, right click, delete, click. Okay. Select show, right click, delete, select.
Okay. Then I'm going to go up to full development, right click and select rebuild. Now there is an option for your surfaces to rebuild automatically.
We don't have to come back and rebuild them dependent on what surface you're working with. You may want to have rebuild automatic turned on. I generally always leave rebuild automatic turned off because I want to know when a surface is out of date.
I want to know if a surface goes out of date and for what reason. And so this gives me a clear signal of why that surface or when that surface goes out of date. And so then I can either choose to come back and rebuild it because I know it's gone out of date, or I need to figure out why it changed.
So I'm going to go ahead and click rebuild. And now we have our surface back to how it was. I'm going to go in here and select out these rectangles that we drew in.
I'm going to click delete, and then I'm going to zoom back out. I'm going to save my drawing, and then I'll meet you in the next video where we are going to talk about some volume surfaces.
