& Construction
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Integrated BIM tools, including Revit, AutoCAD, and Civil 3D
& Manufacturing
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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
Transcript
00:03
The subdivision control cage creates NURBS geometry, not polygons.
00:07
And that means we can use all the NURBS
00:09
Surface and Surface Edit tools on those limit surfaces.
00:13
So to create a blackout for this wheel arch, for example,
00:16
I could use the Draft tool which is like the SubD Extrude.
00:21
And with many of the NURBS tools,
00:23
there is a Chain Select option that is particularly useful
00:25
for the number of small surfaces created by the subdivision.
00:29
So here I can click once and it picks all these edges,
00:33
I can choose a direction
00:35
and a length
00:36
and do a Build.
00:38
And then if I've got a blackout shader, I can apply that
00:42
and I get a useful visualization surface that
00:45
doesn't affect the complexity of the control cage.
00:50
One of the biggest causes of complex SubD geometry
00:53
is using the Bevel tool to create these rounded edges.
00:57
So an alternative is to start with a Crease instead.
01:01
And I'll just isolate the layer to make selection easier.
01:05
And then I could use Round or Surface Fillet.
01:07
So I'll select that
01:09
and then box-select across the whole edge
01:12
and that selects a few more than I need but it'll ignore those.
01:16
So I just need to do a space bar to Build
01:19
and that's trimmed the limit surfaces back
01:22
and built the fillet surfaces in between.
01:25
And it's easy to change the radius here
01:27
and Update.
01:30
So we end up with an accurate and adjustable radius edge
01:33
without adding more edges to the subdivision control cage
01:38
and it maintains history.
01:40
So if I modify the control cage,
01:42
then the fillet updates
01:44
and it can take a while.
01:47
So it's useful to use this H button here and choose Global Suspend
01:52
and then make the changes I want without waiting
01:55
for the surface fillet history to update each time.
01:59
And then when I'm ready for it to be rebuilt,
02:01
then I can go back here and turn off the Suspend.
02:05
And that means you've only got to wait once for the update
02:09
and you can see the fillets reapplied along the edge of those limit surfaces.
02:15
Dealing with holes is tricky with subdivisions.
02:19
So I could drop this trimmed vent surface, for example.
02:22
And here I've got some NURBS detailing tools
02:25
and I'll just use the first one which is Fillet Flange
02:29
and these tools have a lot of settings, so I'll close all those sections.
02:33
And again, here in the Control Options, we've got a Chain Select
02:37
and it's also worth checking the Trim setting which I'll turn on.
02:41
So then I can just click once and select the whole edge
02:45
and then I'll choose the fillet direction and the flange direction,
02:49
I'll just use the default settings and do a space bar to Build.
02:53
And that creates both a fillet and a flange in one go.
02:57
And it's a bit short, so I can increase the flange length here
03:01
and reduce the fillet radius
03:03
and do an Update.
03:07
So that creates quite a refined and crisp surface indent
03:11
again, without affecting the complexity of the SubD.
03:16
I've got a curve-on-surface here for a badge.
03:20
And this time I'll use the Panel Gap tool
03:23
and again, that has a Trim setting and a Chain Select if I need it.
03:28
But this is just one curve, so I'll pick that and say Accept
03:33
and I'll choose the inwards direction
03:35
and it's going to go on both sides so I don't need to change that one
03:39
and it creates a fillet and a flange on both sides.
03:43
And the gap here is a bit wide so I can change that
03:46
and I'll make this radius a bit smaller
03:49
and do an Update.
03:52
So if I want to put a different shade of color onto the badge,
03:55
then the problem is that this surface here is still
03:58
a single surface with just the gap trimmed out.
04:01
So I can't give it two different colors.
04:04
Now, I don't want to affect the rest of the SubD.
04:07
So with just this surface selected, I can do an Untrim
04:11
and then Trim again,
04:13
but I'm going to take the Subdiv Select off because I've got some
04:16
other curves on surface on the SubD that I don't want to trim to.
04:20
So I'll be a bit careful and just trim that one surface and do a Keep.
04:26
And then I can just pick that single surface, do a copy and paste
04:30
and then do an Untrim
04:32
and a re-Trim back to there.
04:35
So I will have lost history, but I can now pick it independently.
04:40
And a useful tool is Pick Surface Chain.
04:43
So I can say, pick everything that's tangent continuous from say this surface.
04:49
And then I can assign a badge color to just that part,
04:55
but mostly you won't need to do that trimming.
04:57
So over here,
04:58
I've used the Panel Gap tool to create the split line between the door and the fender.
05:03
So I don't need to separate the colors,
05:06
but if I want to keep things simple for this split line on the rear edge of the door,
05:11
I can also use the Tubular Offset tool.
05:14
And again, I've got Chain Select
05:17
and I'll go for Automatic trim.
05:20
So I can pick that curve-on-surface chain,
05:23
reduce that tube size.
05:25
And I'll make it quite small for a panel split
05:27
and say Build
05:30
and that's created a tube surface.
05:33
But I can switch to a groove
05:36
or most often I pick None just to trim away the gap.
05:39
And if you've got a dark background,
05:41
that's often good enough to illustrate the split
05:44
or you can switch back to just curves-on-surface and Update
05:49
and then do a Trim Divide.
05:51
And this time I would put the Subdiv Select back on so I'm trimming the whole SubD
05:56
and I could delete that center curve-on-surface or I'll just pick both and say Divide
06:02
and then I can just pick those divided parts and assign a blackout color.
06:09
So if you're familiar with the NURBS modeling tools,
06:12
you've got the option of adding details to the main subdivision concept model
06:16
without creating extra edges and vertices that make
06:19
it harder to make quick design changes.
Video transcript
00:03
The subdivision control cage creates NURBS geometry, not polygons.
00:07
And that means we can use all the NURBS
00:09
Surface and Surface Edit tools on those limit surfaces.
00:13
So to create a blackout for this wheel arch, for example,
00:16
I could use the Draft tool which is like the SubD Extrude.
00:21
And with many of the NURBS tools,
00:23
there is a Chain Select option that is particularly useful
00:25
for the number of small surfaces created by the subdivision.
00:29
So here I can click once and it picks all these edges,
00:33
I can choose a direction
00:35
and a length
00:36
and do a Build.
00:38
And then if I've got a blackout shader, I can apply that
00:42
and I get a useful visualization surface that
00:45
doesn't affect the complexity of the control cage.
00:50
One of the biggest causes of complex SubD geometry
00:53
is using the Bevel tool to create these rounded edges.
00:57
So an alternative is to start with a Crease instead.
01:01
And I'll just isolate the layer to make selection easier.
01:05
And then I could use Round or Surface Fillet.
01:07
So I'll select that
01:09
and then box-select across the whole edge
01:12
and that selects a few more than I need but it'll ignore those.
01:16
So I just need to do a space bar to Build
01:19
and that's trimmed the limit surfaces back
01:22
and built the fillet surfaces in between.
01:25
And it's easy to change the radius here
01:27
and Update.
01:30
So we end up with an accurate and adjustable radius edge
01:33
without adding more edges to the subdivision control cage
01:38
and it maintains history.
01:40
So if I modify the control cage,
01:42
then the fillet updates
01:44
and it can take a while.
01:47
So it's useful to use this H button here and choose Global Suspend
01:52
and then make the changes I want without waiting
01:55
for the surface fillet history to update each time.
01:59
And then when I'm ready for it to be rebuilt,
02:01
then I can go back here and turn off the Suspend.
02:05
And that means you've only got to wait once for the update
02:09
and you can see the fillets reapplied along the edge of those limit surfaces.
02:15
Dealing with holes is tricky with subdivisions.
02:19
So I could drop this trimmed vent surface, for example.
02:22
And here I've got some NURBS detailing tools
02:25
and I'll just use the first one which is Fillet Flange
02:29
and these tools have a lot of settings, so I'll close all those sections.
02:33
And again, here in the Control Options, we've got a Chain Select
02:37
and it's also worth checking the Trim setting which I'll turn on.
02:41
So then I can just click once and select the whole edge
02:45
and then I'll choose the fillet direction and the flange direction,
02:49
I'll just use the default settings and do a space bar to Build.
02:53
And that creates both a fillet and a flange in one go.
02:57
And it's a bit short, so I can increase the flange length here
03:01
and reduce the fillet radius
03:03
and do an Update.
03:07
So that creates quite a refined and crisp surface indent
03:11
again, without affecting the complexity of the SubD.
03:16
I've got a curve-on-surface here for a badge.
03:20
And this time I'll use the Panel Gap tool
03:23
and again, that has a Trim setting and a Chain Select if I need it.
03:28
But this is just one curve, so I'll pick that and say Accept
03:33
and I'll choose the inwards direction
03:35
and it's going to go on both sides so I don't need to change that one
03:39
and it creates a fillet and a flange on both sides.
03:43
And the gap here is a bit wide so I can change that
03:46
and I'll make this radius a bit smaller
03:49
and do an Update.
03:52
So if I want to put a different shade of color onto the badge,
03:55
then the problem is that this surface here is still
03:58
a single surface with just the gap trimmed out.
04:01
So I can't give it two different colors.
04:04
Now, I don't want to affect the rest of the SubD.
04:07
So with just this surface selected, I can do an Untrim
04:11
and then Trim again,
04:13
but I'm going to take the Subdiv Select off because I've got some
04:16
other curves on surface on the SubD that I don't want to trim to.
04:20
So I'll be a bit careful and just trim that one surface and do a Keep.
04:26
And then I can just pick that single surface, do a copy and paste
04:30
and then do an Untrim
04:32
and a re-Trim back to there.
04:35
So I will have lost history, but I can now pick it independently.
04:40
And a useful tool is Pick Surface Chain.
04:43
So I can say, pick everything that's tangent continuous from say this surface.
04:49
And then I can assign a badge color to just that part,
04:55
but mostly you won't need to do that trimming.
04:57
So over here,
04:58
I've used the Panel Gap tool to create the split line between the door and the fender.
05:03
So I don't need to separate the colors,
05:06
but if I want to keep things simple for this split line on the rear edge of the door,
05:11
I can also use the Tubular Offset tool.
05:14
And again, I've got Chain Select
05:17
and I'll go for Automatic trim.
05:20
So I can pick that curve-on-surface chain,
05:23
reduce that tube size.
05:25
And I'll make it quite small for a panel split
05:27
and say Build
05:30
and that's created a tube surface.
05:33
But I can switch to a groove
05:36
or most often I pick None just to trim away the gap.
05:39
And if you've got a dark background,
05:41
that's often good enough to illustrate the split
05:44
or you can switch back to just curves-on-surface and Update
05:49
and then do a Trim Divide.
05:51
And this time I would put the Subdiv Select back on so I'm trimming the whole SubD
05:56
and I could delete that center curve-on-surface or I'll just pick both and say Divide
06:02
and then I can just pick those divided parts and assign a blackout color.
06:09
So if you're familiar with the NURBS modeling tools,
06:12
you've got the option of adding details to the main subdivision concept model
06:16
without creating extra edges and vertices that make
06:19
it harder to make quick design changes.
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