Explore the process of creating simple surfaces and understanding surface-to-surface interaction in creating a new combination surface. Find out how to define specific elevations, create multiple surfaces, and understand the order of operations in pasting surfaces.
Key Insights
- Creating simple surfaces involves defining rectangles at specific elevations, offsetting rectangles, and then designating these as surfaces. The process also includes setting specific styles and choosing to leave certain factors unchanged.
- Surface-to-surface interaction involves creating multiple surfaces; for instance, one small and one large. These surfaces can be manipulated to form complex shapes such as a downward basin with an upward hill inside it.
- The order of operations while pasting surfaces is crucial in successfully creating a combination surface. The larger surface must be built first, followed by the smaller surface, to ensure all data is accurately represented in the final model.
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In this video, we're going to go ahead and create two very simple surfaces and then talk about surface-to-surface interaction when you're doing pasting of surfaces into a new combination surface. So I'm going to go ahead and navigate over to the right-hand side of my surface over here, and I'm going to draw in a rectangle.
From this rectangle, I'm going to go ahead and offset that initial rectangle inwards 50 feet. I'm going to do another offset of the inner rectangle by another 50 feet, and then I'm going to offset that third rectangle inwards by 10 feet. So from here, I'm going to go ahead and define these rectangles as at specific elevations.
I'm going to go ahead and right-click. I'm going to choose properties. I'm going to navigate this window over here.
I'm going to choose elevation. I'm going to set my outer rectangle at 100. I'm going to select my second rectangle.
I'm going to set it at an elevation of 75. I'm going to select my third rectangle. I'm going to set it as an elevation of 75 as well, and then I'm going to select my inner rectangle, and I'm going to set it as an elevation of 85.
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So from here, I'm going to go ahead and close my properties window. I'm going to navigate over to surfaces in my prospector tab of my tool space. I'm going to go ahead and select it, right-click, and click create surface.
I'm going to create two surfaces. So I'm going to create the first one. I'm going to create my large surface, and I'm going to go ahead and set my style as 2 in 10 background, and I'm going to click okay.
Then I'm going to go ahead and go to large, open my definitions, go to contours, right-click, select add. I'm not going to put a description in. I'm going to leave the weeding factors as is and the supplementing factors as is.
I'm also going to leave the minimize flat areas information in here as is. So I'm going to go ahead and click okay. I'm going to do a window crossing across the outer two rectangles and hit ENTER, and then I'm going to go ahead and go back into surfaces in my tool space prospector tab, right-click, create surface.
I'm going to type in a new name and type small. I'm going to accept contours 2 in 10 background as my style, and I'm going to click okay. Now I'm going to minimize my large, expand my small, expand definitions, go to contours, right-click, select add, leave all of the information as it shows up in this window and click okay, and do a window crossing across the inside two rectangles and hit ENTER.
Now what I have is I have two surfaces, one small and one large, and if I go ahead and I select both of these by picking a contour on the outside and on the inside and selecting object viewer, what we will see here is that we have a downward basin and then an upward hill inside of that basin. We're going to work with these two surfaces. What you'll notice
right now is that if I go and I look at the bottom side of this, you can see I have a flat plane across the bottom of my basin and that I can see the rectangle for that hill that's inside of it.
So what we're going to do next is we're going to go ahead and create one more surface. We're going to right-click, create surface, and we're going to go ahead and call this combo. I'm going to go ahead and click okay.
I'm going to minimize my full development, maximize my combo, maximize definitions for my combo surface, and I'm going to go to edits. I'm going to right-click on my edits, and I'm going to go ahead and go to paste surface. I'm going to select paste surface.
I'm going to go ahead and I'm going to select large and click okay. What I'm going to do next is I'm going to right-click on edits. I'm going to paste surface again, and this time I'm going to select small and click okay.
So from here, what I'm going to go ahead and do is I'm going to turn my large and small surfaces off. I'm going to right-click, select surface properties, go to information tab, drop down, set it to no display, click apply, click okay. I'm going to go to small, right-click, surface properties, drop down surface style, select no display, click apply, click okay.
So from here now, the only surface being displayed is my combo surface. I can check that by selecting a contour and up in the contextual ribbon bar, you'll see it says tin surface combo. This is my combo surface that I've selected.
If I go to object viewer, what you'll notice is that if I rotate this into three-dimensional view, it looks identical, except that when I come underneath, you'll notice this, that my inner surface now does not have that flat plane, and that's because of order of operations. If I go and I close this window, I go to my combo surface, I right-click and select surface properties and navigate to definition. What you'll see here is that the order of operations for this surface is to add in my surface large and then to add in my surface small.
Now, what's happening here is that my surface small does not have a plane going from one side of the outer edge across to the other side of the outer edge and creating a flat bottom underneath. That's why we can see the underside of our small surface being copied into our larger surface. Now, if I go ahead and I change the operation order by selecting paste, add small surface and promoting it upwards to the top, you're going to notice I get an error here that says that these need to be redrawn.
I can click apply, rebuild surface, and then click okay. And when I do that, you're going to notice that the contours on the inside disappeared, and that's because if you go to object viewer, you will notice that my inner hill is not there anymore. And the reason that my inner hill is not there anymore is that the order of operation was to add in my inner hill surface and then to add my outer surface or my large surface.
So I have my small surface added and then my large surface added. Well, my large surface has this large flat plane on the inside of my basin. And so the data from that large flat plane overwrote all of the data for my hill on the inside of my small surface.
So that is an example of why your order of operations inside of your definitions tab matters is because I have lost all of this data. I had to put in my large surface first and then my small
surface in order for both of them to show up. If for some reason you ever did a paste surface edit, what you're going to go ahead and make sure you do is you're going to make sure that your small information or your small data needs to come after your larger information or your larger data.
So I'm going to go ahead and hit apply, rebuild, select okay. And if I look at this object in object viewer again, what you're going to see now is that I now have that hill in the middle. My small surface is now showing up because Civil 3D is building the large surface first and then building the small surface after that.
