before we build a surface the first thing I'm going to do is just save the drawing and now let's get these points ready to use in a surface a really good practice is to create a point group of all the points that you're going to use to build your surface so I'm going to call this point group eg topo and instead of going to the include tab and choosing points rather by number or description I'm just going to go to point groups and I'm going to check 10 for 16 that's going to include all the points from our survey import down in the previous exercise if there are any points I don't want to include from that point group I can go to the exclude tab and exclude them based on number or description so let's say I had some inverts in my survey those inverts are going to mess up my surface so I might say I don't want to include or rather I want to exclude points with a description matching inv star if you're wondering why those points all just turned on when I did that go back to the previous tutorial to see more information about the management of points and how they're displayed so now I can see all my points and we're ready to build a surface using that eg topo point group to build a surface I'll go to the prospector tab of tool space find surfaces I click and say create surface give it an appropriate name and choose a style we're going to choose the style 2 foot and 10 foot background 2 foot and 10 foot are going to control the contour intervals or the spacing between contours and background is going to control the color and layer of our contours the underlying surface definition is actually a tin which stands for triangular irregular Network and the style just decides how we display it once I've created that surface you'll see a plus appear next to surfaces in prospector and a plus next to eg and under definition these are the types of objects that we can add to a surface so the civil3d can build the triangular network in our case we've got a point group all set up eg topo so under definition for eg I'll go down to point groups right click say add and choose eg topo just by adding that point group the program is going to triangulate between all my points it's going to take those triangles and find contours along them and there's the display so you can see that the background surface style gave me these gray contours let's say it was a design surface and I wanted to choose a different style to display it the easiest way to do that is to select the surface and up on the ribbon you get a contextual ribbon tab where you can go to surface properties or after selecting you can right click and go to surface properties and then finally in prospector you can actually right click on the surface name itself eg go to surface properties any one of those three ways we get ourselves two surface properties and we can change the style so I sent down one of this to be a design surface I'll change it to two and ten design hit OK you can see the contours change their color another common action is to set it to a no display style got multiple surfaces I don't necessarily want to see them all although I might need them for volume calculations or profiles or something like that now when I set it to a no display style the surface still exists in the drawing but I can't see it to get it turned back on I can't select it in the drawing area I can only select it in prospector go to surface properties that way and set it to a different style so I'm going to set it to contours and triangles now remember triangles are actually the underlying definition of the surface and then I'm going to go and look at these Ridge points and what I'm going to see is for instance right here the surface hasn't triangulated the way I'd like it to I would like it to try and give it between Ridge lines and you can see that it didn't the best way to take care of this is to draw in 3d polyline break lines and add them to the surface definition to make that easy to do I'm going to set the surface back again to a no display style and I'm going to use my point groups to display only the ridge points next I'll draw a 3d polyline from point object to point object and there's two easy ways to pick up point objects one is with the node oh snap you'll see it picks up the node I might want to turn everything else off another way is with the transparent commands we actually have a point object transparent command I think I'll run that allows me to pick anywhere on the point object and so I'll just draw in this 3d polyline from Ridge point to Ridge point now I'll set my surface back to the triangle display and I'm ready to add in the breakline well zoom back into the problem location so we can see it change I will select the break line under surface definition I'll go to break lines right click Add give it a description of Ridge the primary type of break line you're going to use is standard break line you may occasionally use proximity the standard break line actually uses the elevation data from the break line in the surface definition a proximity break line does not use elevation data so if you had brought in a 2d polyline for this Ridge I would probably want to use the proximity type but we drew a 3d polyline snapped to the correct elevations of the points so we'll use standard weeding factors can be used to get rid of vertices on your break line and supplementing factors are used to automatically add vertices to your break line I'll say ok and you'll see that the triangulation and the contours changed now the next thing we'll want to do with this surface is look at the boundary I'm going to start by turning all my points back on so I can compare the surface boundary to the points and it definitely looks like I have some triangulation it really isn't valid so I'm going to draw in a 2d polyline boundary and first I'm going to put it on a correct layer I think I'll use that point object transparent command again I'll just go around picking my points [Music] and once I've got that closed boundary I'm ready to add it to the surface so go back over to prospector tab of tool space look under the definition for my EG surface go to boundaries click right click go to add it is an outer boundary say ok and because I didn't have the polyline selected before I added the boundary I have to pick it now so I looked at my command line it says select object select that boundary and you can see that the surface clips at that boundary so in the next tutorial I'll show you how to use data shortcut to make this eg surface available in our design drawing where we'll then paid alignments and profiles