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Link and create a toposurface from a DWG file.
Type:
Tutorial
Length:
8 min.
Tutorial resources
These downloadable resources will be used to complete this tutorial:
Transcript
00:04
The top I surface is a representation of the ground around the site.
00:09
And maps will often show contour lines to
00:11
indicate the elevation and slope of the ground.
00:14
And drawings will often display spot elevations in plans
00:17
to show the height at specific locations.
00:21
It is important to have an accurate Toppo surface modeled for a site
00:24
as it will influence the exact layout and location of the building.
00:30
And here we can see we have some
00:31
buildings modeled but there's no topography modeled around them
00:36
to create a top by surface. For this. We'll use the contour data in a CAD drawing
00:41
that needs to be linked into the project.
00:44
So first
00:45
from the project browser, we'll open the site plan view
00:50
and now we'll go to the insert ribbon tab
00:53
and from the link panel, we'll click on link head.
00:58
Now you'll need to browse to where you have the exercise files saved
01:03
and also like the DWG file site contours
01:07
from the options at the bottom.
01:09
Here, we'll uncheck the correct lines that are slightly off access option.
01:13
This is because the contour lines in the DWG are all at varying angles
01:18
and we want to retain any that are slightly off from horizontal or vertical
01:22
in their actual drawn angle.
01:26
For the position in here, we'll set this to be manual center.
01:32
Now
01:33
we'll click open
01:34
and the site contours DWG will be linked into the file
01:38
with the center of the DWG at the mouse cursor.
01:41
And we just need to place it to this bank of contours here
01:45
runs through the location of the building.
01:49
Now we'll switch back to the 3D view
01:51
and we can see the contours from the DWG.
01:53
They are arranged in the 3D space and surround our buildings.
02:00
No,
02:02
from the project browser, we'll open the east elevation view
02:06
and we can also see we have the contours visible in
02:09
here and how they relate to the elevation of our building
02:13
to create the Toppo surface. We'll first swap back to the 3D view
02:17
and then from the masin and site
02:19
tab
02:20
on the model site panel, we'll click the top o surface tool
02:27
looking at the edit surface ribbon. We can see that the place point tool is active
02:32
and a topo surface is defined by individual points
02:36
that are connected to create a triangulated surface.
02:40
However, placing the points individually is quite a laborious task
02:44
and hence having rev
02:45
place them automatically along the contour lines in AD WG
02:49
is the preferred option.
02:51
So to do this
02:53
from the tools panel here, we'll click the create from import button
02:57
and then we'll choose select import instance
03:02
now we just need to click on the DWG in the view to select it.
03:06
And now we'll be prompted to choose the layers from within the DWG
03:10
that contain the contours.
03:13
So looking at the layer names here,
03:14
we can see that we have one called contours and this is the only one that we need.
03:19
So from the buttons on the right hand side,
03:21
we'll click check none.
03:23
And now from the list of layers here, we'll just recheck the contours layer
03:27
and then we can click. OK.
03:31
And we can see that the points have been traced along each of those contour lines
03:35
and the top surface created
03:38
zooming in a little closer. We can see the red lines of the contours in the DWG
03:42
and the points that have been placed on those contour lines to create that surface.
03:49
Due to the nature of the contours within CAD data,
03:52
they can sometimes create multiple points that are very close together.
03:56
And this can cause anomalies within the surface
04:00
to help with this.
04:01
We'll go to the edit surface ribbon and from the tools panel here,
04:05
we'll click simplify surface.
04:09
Now, we can see we have an accuracy setting of three inches.
04:12
This means it will look within a three inch radius of each point.
04:16
And if it finds other points, it will merge them together,
04:19
we'll leave the accuracy set in as three inches and click. OK?
04:23
And now we can see that the number of points has been reduced in the surface and
04:27
they should give us a smoother surface to work with.
04:33
So that finish is creating the topo surface.
04:36
So from the edit surface ribbon here, we'll click finish edit mode.
04:42
Now, the CAD drawing is still visible,
04:44
we can see the red contours lines here and it
04:46
makes it look a little bit confusing in the view.
04:49
So we'll go to the insert ribbon tab and from the link panel,
04:53
we'll click manage links.
04:56
Now we'll go to the cab format tab where we can see the site contours DWG.
05:01
So we'll click on this and then from the buttons at the bottom here, I'll click unload
05:05
so that will unload it from the file and it will no longer be visible within the model.
05:10
Obviously, if we needed to,
05:11
we can always click reload to bring it back into the model.
05:15
So I'll click. OK.
05:17
And now we can see we have just the contours from the top post surface here.
05:21
So to be able to control these, we'll go back to the
05:24
mall and site ribbon tab.
05:26
And from the model site panel here,
05:28
we'll click to open the site settings.
05:32
So in here,
05:32
we can see we have our primary contour lines at intervals of 10 ft vertically.
05:37
And below this here we have some secondary contours that are spaced every 1 ft apart.
05:42
So we can click into this and set this to 2 ft.
05:46
And when I click apply.
05:47
Now,
05:47
we can see that those contours are spaced every 2 ft and there's a lot less in the view
05:52
equally. We could change the increment to six inches.
05:56
And when we click apply,
05:58
we can see we have a lot more contours spaced at six inches vertically. Now
06:02
I'll change the setting back to 1 ft and we'll click ok
06:06
to revert back to the original setting.
06:08
And now we're swapped at a site plan view
06:11
and we can see the top of surface in here
06:14
with the contours being displayed as well.
06:17
And it can be useful to have each contour labeled with its elevation.
06:22
As this helps us understand in the plan,
06:24
the slope of the ground around the building.
06:28
So to do this from the mass
06:29
and site tab
06:31
on the modify site panel here, we'll click the label contours tool.
06:36
And now all we need to do is draw a line through the contours that we want to be labeled.
06:41
So we'll click here and then track in across right to the other side of the site.
06:45
We'll click again
06:48
and then straight away here, we can see that each contour has its elevation value.
06:51
So starting at zero at the bottom and going up in one for increments here,
06:56
that's gonna make it a lot easier for us to understand
06:58
the slopes around the building when looking in the plan view.
07:03
So we swap back to the 3D view
07:06
and that finishes creating the top of surface for this site.
Video transcript
00:04
The top I surface is a representation of the ground around the site.
00:09
And maps will often show contour lines to
00:11
indicate the elevation and slope of the ground.
00:14
And drawings will often display spot elevations in plans
00:17
to show the height at specific locations.
00:21
It is important to have an accurate Toppo surface modeled for a site
00:24
as it will influence the exact layout and location of the building.
00:30
And here we can see we have some
00:31
buildings modeled but there's no topography modeled around them
00:36
to create a top by surface. For this. We'll use the contour data in a CAD drawing
00:41
that needs to be linked into the project.
00:44
So first
00:45
from the project browser, we'll open the site plan view
00:50
and now we'll go to the insert ribbon tab
00:53
and from the link panel, we'll click on link head.
00:58
Now you'll need to browse to where you have the exercise files saved
01:03
and also like the DWG file site contours
01:07
from the options at the bottom.
01:09
Here, we'll uncheck the correct lines that are slightly off access option.
01:13
This is because the contour lines in the DWG are all at varying angles
01:18
and we want to retain any that are slightly off from horizontal or vertical
01:22
in their actual drawn angle.
01:26
For the position in here, we'll set this to be manual center.
01:32
Now
01:33
we'll click open
01:34
and the site contours DWG will be linked into the file
01:38
with the center of the DWG at the mouse cursor.
01:41
And we just need to place it to this bank of contours here
01:45
runs through the location of the building.
01:49
Now we'll switch back to the 3D view
01:51
and we can see the contours from the DWG.
01:53
They are arranged in the 3D space and surround our buildings.
02:00
No,
02:02
from the project browser, we'll open the east elevation view
02:06
and we can also see we have the contours visible in
02:09
here and how they relate to the elevation of our building
02:13
to create the Toppo surface. We'll first swap back to the 3D view
02:17
and then from the masin and site
02:19
tab
02:20
on the model site panel, we'll click the top o surface tool
02:27
looking at the edit surface ribbon. We can see that the place point tool is active
02:32
and a topo surface is defined by individual points
02:36
that are connected to create a triangulated surface.
02:40
However, placing the points individually is quite a laborious task
02:44
and hence having rev
02:45
place them automatically along the contour lines in AD WG
02:49
is the preferred option.
02:51
So to do this
02:53
from the tools panel here, we'll click the create from import button
02:57
and then we'll choose select import instance
03:02
now we just need to click on the DWG in the view to select it.
03:06
And now we'll be prompted to choose the layers from within the DWG
03:10
that contain the contours.
03:13
So looking at the layer names here,
03:14
we can see that we have one called contours and this is the only one that we need.
03:19
So from the buttons on the right hand side,
03:21
we'll click check none.
03:23
And now from the list of layers here, we'll just recheck the contours layer
03:27
and then we can click. OK.
03:31
And we can see that the points have been traced along each of those contour lines
03:35
and the top surface created
03:38
zooming in a little closer. We can see the red lines of the contours in the DWG
03:42
and the points that have been placed on those contour lines to create that surface.
03:49
Due to the nature of the contours within CAD data,
03:52
they can sometimes create multiple points that are very close together.
03:56
And this can cause anomalies within the surface
04:00
to help with this.
04:01
We'll go to the edit surface ribbon and from the tools panel here,
04:05
we'll click simplify surface.
04:09
Now, we can see we have an accuracy setting of three inches.
04:12
This means it will look within a three inch radius of each point.
04:16
And if it finds other points, it will merge them together,
04:19
we'll leave the accuracy set in as three inches and click. OK?
04:23
And now we can see that the number of points has been reduced in the surface and
04:27
they should give us a smoother surface to work with.
04:33
So that finish is creating the topo surface.
04:36
So from the edit surface ribbon here, we'll click finish edit mode.
04:42
Now, the CAD drawing is still visible,
04:44
we can see the red contours lines here and it
04:46
makes it look a little bit confusing in the view.
04:49
So we'll go to the insert ribbon tab and from the link panel,
04:53
we'll click manage links.
04:56
Now we'll go to the cab format tab where we can see the site contours DWG.
05:01
So we'll click on this and then from the buttons at the bottom here, I'll click unload
05:05
so that will unload it from the file and it will no longer be visible within the model.
05:10
Obviously, if we needed to,
05:11
we can always click reload to bring it back into the model.
05:15
So I'll click. OK.
05:17
And now we can see we have just the contours from the top post surface here.
05:21
So to be able to control these, we'll go back to the
05:24
mall and site ribbon tab.
05:26
And from the model site panel here,
05:28
we'll click to open the site settings.
05:32
So in here,
05:32
we can see we have our primary contour lines at intervals of 10 ft vertically.
05:37
And below this here we have some secondary contours that are spaced every 1 ft apart.
05:42
So we can click into this and set this to 2 ft.
05:46
And when I click apply.
05:47
Now,
05:47
we can see that those contours are spaced every 2 ft and there's a lot less in the view
05:52
equally. We could change the increment to six inches.
05:56
And when we click apply,
05:58
we can see we have a lot more contours spaced at six inches vertically. Now
06:02
I'll change the setting back to 1 ft and we'll click ok
06:06
to revert back to the original setting.
06:08
And now we're swapped at a site plan view
06:11
and we can see the top of surface in here
06:14
with the contours being displayed as well.
06:17
And it can be useful to have each contour labeled with its elevation.
06:22
As this helps us understand in the plan,
06:24
the slope of the ground around the building.
06:28
So to do this from the mass
06:29
and site tab
06:31
on the modify site panel here, we'll click the label contours tool.
06:36
And now all we need to do is draw a line through the contours that we want to be labeled.
06:41
So we'll click here and then track in across right to the other side of the site.
06:45
We'll click again
06:48
and then straight away here, we can see that each contour has its elevation value.
06:51
So starting at zero at the bottom and going up in one for increments here,
06:56
that's gonna make it a lot easier for us to understand
06:58
the slopes around the building when looking in the plan view.
07:03
So we swap back to the 3D view
07:06
and that finishes creating the top of surface for this site.
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