Integrated BIM tools, including Revit, AutoCAD, and Civil 3D
Professional CAD/CAM tools built on Inventor and AutoCAD
Create a fit point spline and a control point (CV) spline, and understand their differences.
Type:
Tutorial
Length:
4 min.
Transcript
00:04
Let's talk about splines.
00:06
A spine is defined
00:08
in the documentation for Autocad
00:10
as a smooth curve that passes through or near a
00:14
set of points that influence the shape of the curve.
00:20
You can think of it as Autocad smoothed it out.
00:24
For me, it's very different than curved segments within a polyline,
00:28
a spline smooths curves.
00:31
But when you click on it,
00:32
you will notice that the control points are not directly on the geometry.
00:37
Spines are used in situations where the appearance of smooth curve geometry is key
00:42
and they provide you with a quick and easy way to create those smooth curves.
00:47
Splines have been improved in recent versions of Autocad
00:50
and you can easily control them with grip editing.
00:55
When creating spines in Autocad,
00:58
you have the choice of using fit points or control points.
01:01
If you have a tight area to create a spine in,
01:04
you might want to use fit points as fit points
01:07
for a spine work in a similar way as poly lines
01:11
in that the vertices lie directly on the geometry of the spine.
01:17
Control points would be used in situations where you want
01:20
to have more control over the vertices through grip,
01:24
edits,
01:25
control points work a little bit differently as we will see shortly.
01:30
Let's create our first spline using the fit points option.
01:35
For this example,
01:36
we will go through using a Spline to create
01:39
a meandering sidewalk where smooth curve geometry is essential
01:45
to access this command. You can type in Spline
01:49
and then once you
01:51
click enter,
01:53
you can choose the method option
01:55
and then choose from fit
01:58
or CV,
02:02
specify our first point.
02:06
And as we drag the cursor along,
02:13
we get smooth curves.
02:17
Now to finish the meandering sidewalk, we can use the offset command
02:23
offset with a distance of five
02:30
and there we have it.
02:34
Once the spine has been created,
02:37
we can click on it
02:40
and notice the grips that it has,
02:44
you can change it from
02:45
fit to control vertices with the grips
02:50
and the grips are located directly
02:53
on top of the spine.
02:57
If we change it to control vertices,
03:01
then you can see the difference in where
03:05
the control points show up
03:11
next. We will create a Spline using the control points option
03:16
to access his command.
03:18
As before
03:19
you can simply type in Spline,
03:25
choose the method
03:27
and then choose CV,
03:31
click points on the screen.
03:34
And you can see that
03:36
this method acts a little bit more
03:40
like arcs
03:45
once created.
03:46
When you click on this type of spine, you can see that the
03:51
grips are not directly on top of the geometry.
03:57
The control vertices
03:59
as the name states gives you more control to grip, edit the vertices.
Video transcript
00:04
Let's talk about splines.
00:06
A spine is defined
00:08
in the documentation for Autocad
00:10
as a smooth curve that passes through or near a
00:14
set of points that influence the shape of the curve.
00:20
You can think of it as Autocad smoothed it out.
00:24
For me, it's very different than curved segments within a polyline,
00:28
a spline smooths curves.
00:31
But when you click on it,
00:32
you will notice that the control points are not directly on the geometry.
00:37
Spines are used in situations where the appearance of smooth curve geometry is key
00:42
and they provide you with a quick and easy way to create those smooth curves.
00:47
Splines have been improved in recent versions of Autocad
00:50
and you can easily control them with grip editing.
00:55
When creating spines in Autocad,
00:58
you have the choice of using fit points or control points.
01:01
If you have a tight area to create a spine in,
01:04
you might want to use fit points as fit points
01:07
for a spine work in a similar way as poly lines
01:11
in that the vertices lie directly on the geometry of the spine.
01:17
Control points would be used in situations where you want
01:20
to have more control over the vertices through grip,
01:24
edits,
01:25
control points work a little bit differently as we will see shortly.
01:30
Let's create our first spline using the fit points option.
01:35
For this example,
01:36
we will go through using a Spline to create
01:39
a meandering sidewalk where smooth curve geometry is essential
01:45
to access this command. You can type in Spline
01:49
and then once you
01:51
click enter,
01:53
you can choose the method option
01:55
and then choose from fit
01:58
or CV,
02:02
specify our first point.
02:06
And as we drag the cursor along,
02:13
we get smooth curves.
02:17
Now to finish the meandering sidewalk, we can use the offset command
02:23
offset with a distance of five
02:30
and there we have it.
02:34
Once the spine has been created,
02:37
we can click on it
02:40
and notice the grips that it has,
02:44
you can change it from
02:45
fit to control vertices with the grips
02:50
and the grips are located directly
02:53
on top of the spine.
02:57
If we change it to control vertices,
03:01
then you can see the difference in where
03:05
the control points show up
03:11
next. We will create a Spline using the control points option
03:16
to access his command.
03:18
As before
03:19
you can simply type in Spline,
03:25
choose the method
03:27
and then choose CV,
03:31
click points on the screen.
03:34
And you can see that
03:36
this method acts a little bit more
03:40
like arcs
03:45
once created.
03:46
When you click on this type of spine, you can see that the
03:51
grips are not directly on top of the geometry.
03:57
The control vertices
03:59
as the name states gives you more control to grip, edit the vertices.
Industry:
How to buy
Privacy | Do not sell or share my personal information | Cookie preferences | Report noncompliance | Terms of use | Legal | © 2025 Autodesk Inc. All rights reserved
Sign in for the best experience
Save your progress
Get access to courses
Receive personalized recommendations
May we collect and use your data?
Learn more about the Third Party Services we use and our Privacy Statement. May we collect and use your data to tailor your experience?
Explore the benefits of a customized experience by managing your privacy settings for this site or visit our Privacy Statement to learn more about your options.