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Professional CAD/CAM tools built on Inventor and AutoCAD
Integrated BIM tools, including Revit, AutoCAD, and Civil 3D
Professional CAD/CAM tools built on Inventor and AutoCAD
Analyze and edit TIN surfaces in Civil 3D, including adjusting point visibility, modifying survey and surface points, removing triangles, and rebuilding out-of-date surfaces.
Type:
Tutorial
Length:
6 min.
Transcript
00:03
In Civil 3D. TIN surfaces are made up of triangles that connect data points, creating a detailed terrain model.
00:11
By analyzing and refining these triangles,
00:14
you can ensure that the surface accurately represents real-world conditions;
00:18
that any irregularities in the surface are smoothed out;
00:22
that any errors in your design are minimized;
00:26
and that you have a clear, realistic visualization of the surface.
00:31
To modify a TIN surface in Civil 3D,
00:34
begin with a drawing open and a TIN surface already created from point groups.
00:39
In this example, there is an issue with the contours becoming very steep in certain areas.
00:45
To resolve this type of issue, it is important to discuss with the surveyor what the site looks like.
00:51
In this case, it was revealed that the surveyor took invert elevations on,
00:56
rather than ground shots of, a couple of points.
00:59
To modify these points, the display order of the point groups must be changed
01:04
so that they are visible in the drawing.
01:06
From the Toolspace, Prospector tab, right-click Point Groups and select Properties..
01:14
From the Point Groups dialog, use the directional arrows to change the display order of the point groups.
01:21
In this case, the TOPO group is moved to the top.
01:25
Click Apply, and then click OK.
01:29
The points now display in the drawing and can be modified.
01:33
Right-click a point and select Edit Points to open the Point Editor,
01:37
where you can adjust the point information as needed.
01:41
In this case, the Point Elevation is adjusted using information obtained from the surveyor.
01:47
Click the checkmark to apply the change.
01:51
Notice that in the drawing, the surface issue remains, despite point corrections,
01:56
and in the Toolspace, Prospector tab, you see a warning icon adjacent to Surfaces.
02:03
This indicates that the surface is out-of-date.
02:08
Right-click Surfaces and select Rebuild Out of Date Items.
02:12
The Events Viewer vista displays in the Panorama window.
02:17
Select the checkmark to rebuild the surface.
02:20
The surface is rebuilt and updated in the drawing.
02:25
You can also modify surfaces by modifying the TIN.
02:30
First, the triangles must be visible.
02:33
In the drawing, pick the surface.
02:36
Then, from the contextual ribbon, Modify panel,
02:40
expand Surface Properties and select Edit Surface Style.
02:45
In the Surface Style dialog, open the Display tab.
02:49
From the Component display group, toggle ON the visibility for Triangles.
02:54
Click OK, and the drawing updates.
02:58
In this case, to erase the triangles that are triangulating out to a specific point,
03:04
with the surface still selected, from the contextual ribbon,
03:08
expand the Edit Surface drop-down and select Delete Line.
03:13
When prompted, select the edges of the triangles to be deleted, then press ENTER.
03:20
One was missed, but the surface looks much cleaner now.
03:25
From the ribbon, expand the Edit Surface drop-down again to see that from here,
03:29
you could also select Modify Point.
03:32
If you choose to modify points, please note that these are surface points, not survey points.
03:38
As soon as you modify a surface point, it will override any survey point elevations,
03:44
and no longer connect to the survey points, as seen previously.
03:48
If you need to view the surface in different ways, with the surface still selected,
03:54
right-click it and select Object Viewer.
03:57
In the Object Viewer, you can pan and orbit the surface without changing the world coordinates of the model.
04:05
In this case, you can see an issue in the surface where a few of the contours are going to a point.
04:11
Close the Object Viewer.
04:15
You can resolve this issue by modifying a surface point,
04:19
but first you need to make the surface points visible.
04:23
Open the Point Groups dialog, and in this case, move _All Points to the top of the list,
04:28
which will make the survey points in the drawing no longer visible.
04:33
Back in the drawing, select the surface and open the Surface Style dialog.
04:38
From the Display tab, toggle ON the visibility for Points, and then click OK.
04:45
Now, from the ribbon, expand the Edit Surface drop-down and select Modify Point.
04:52
In the drawing, pick the point to modify, then press ENTER.
04:58
You are prompted to enter a new elevation for the point.
05:02
Adjust the elevation—, which, in this case, was obtained from the surveyor—then press ENTER again to confirm.
05:09
Because this change was made to the surface point and not the survey point,
05:14
the elevation for the survey point was not changed.
05:17
Refining TIN surfaces in Civil 3D ensures accurate and realistic 3D visualizations.
Video transcript
00:03
In Civil 3D. TIN surfaces are made up of triangles that connect data points, creating a detailed terrain model.
00:11
By analyzing and refining these triangles,
00:14
you can ensure that the surface accurately represents real-world conditions;
00:18
that any irregularities in the surface are smoothed out;
00:22
that any errors in your design are minimized;
00:26
and that you have a clear, realistic visualization of the surface.
00:31
To modify a TIN surface in Civil 3D,
00:34
begin with a drawing open and a TIN surface already created from point groups.
00:39
In this example, there is an issue with the contours becoming very steep in certain areas.
00:45
To resolve this type of issue, it is important to discuss with the surveyor what the site looks like.
00:51
In this case, it was revealed that the surveyor took invert elevations on,
00:56
rather than ground shots of, a couple of points.
00:59
To modify these points, the display order of the point groups must be changed
01:04
so that they are visible in the drawing.
01:06
From the Toolspace, Prospector tab, right-click Point Groups and select Properties..
01:14
From the Point Groups dialog, use the directional arrows to change the display order of the point groups.
01:21
In this case, the TOPO group is moved to the top.
01:25
Click Apply, and then click OK.
01:29
The points now display in the drawing and can be modified.
01:33
Right-click a point and select Edit Points to open the Point Editor,
01:37
where you can adjust the point information as needed.
01:41
In this case, the Point Elevation is adjusted using information obtained from the surveyor.
01:47
Click the checkmark to apply the change.
01:51
Notice that in the drawing, the surface issue remains, despite point corrections,
01:56
and in the Toolspace, Prospector tab, you see a warning icon adjacent to Surfaces.
02:03
This indicates that the surface is out-of-date.
02:08
Right-click Surfaces and select Rebuild Out of Date Items.
02:12
The Events Viewer vista displays in the Panorama window.
02:17
Select the checkmark to rebuild the surface.
02:20
The surface is rebuilt and updated in the drawing.
02:25
You can also modify surfaces by modifying the TIN.
02:30
First, the triangles must be visible.
02:33
In the drawing, pick the surface.
02:36
Then, from the contextual ribbon, Modify panel,
02:40
expand Surface Properties and select Edit Surface Style.
02:45
In the Surface Style dialog, open the Display tab.
02:49
From the Component display group, toggle ON the visibility for Triangles.
02:54
Click OK, and the drawing updates.
02:58
In this case, to erase the triangles that are triangulating out to a specific point,
03:04
with the surface still selected, from the contextual ribbon,
03:08
expand the Edit Surface drop-down and select Delete Line.
03:13
When prompted, select the edges of the triangles to be deleted, then press ENTER.
03:20
One was missed, but the surface looks much cleaner now.
03:25
From the ribbon, expand the Edit Surface drop-down again to see that from here,
03:29
you could also select Modify Point.
03:32
If you choose to modify points, please note that these are surface points, not survey points.
03:38
As soon as you modify a surface point, it will override any survey point elevations,
03:44
and no longer connect to the survey points, as seen previously.
03:48
If you need to view the surface in different ways, with the surface still selected,
03:54
right-click it and select Object Viewer.
03:57
In the Object Viewer, you can pan and orbit the surface without changing the world coordinates of the model.
04:05
In this case, you can see an issue in the surface where a few of the contours are going to a point.
04:11
Close the Object Viewer.
04:15
You can resolve this issue by modifying a surface point,
04:19
but first you need to make the surface points visible.
04:23
Open the Point Groups dialog, and in this case, move _All Points to the top of the list,
04:28
which will make the survey points in the drawing no longer visible.
04:33
Back in the drawing, select the surface and open the Surface Style dialog.
04:38
From the Display tab, toggle ON the visibility for Points, and then click OK.
04:45
Now, from the ribbon, expand the Edit Surface drop-down and select Modify Point.
04:52
In the drawing, pick the point to modify, then press ENTER.
04:58
You are prompted to enter a new elevation for the point.
05:02
Adjust the elevation—, which, in this case, was obtained from the surveyor—then press ENTER again to confirm.
05:09
Because this change was made to the surface point and not the survey point,
05:14
the elevation for the survey point was not changed.
05:17
Refining TIN surfaces in Civil 3D ensures accurate and realistic 3D visualizations.
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