You are reading an old version of this user guide. The information contained here has been archived and is presented for reference reasons, but it may not be up to date.

## 3.25. coons command

Description: Creates a coons patch through a selected loop of 2, 3 or 4 curves.

Inline mode usage:

• coons -h: Displays the help file that summarizes the parameters for this command.
• coons –s all: Selects all curves of the scene.
• coons –s <name>: Selects <name> curve.

Interactive mode usage:

• Invocation: coons
• Parameters:
• Two, three or four curves used for the creation of the coons patch. The set of selected curves must form a closed loop.

Example:

We are going to create a coons patch from a set of four curves, so the first step is to create the curves. For this, we will use the curveInterpolation command:

>curveInterpolation

Degree [3]: 3

Select curve points [Press Enter when done]

Point 0 [x y z]: 0 0 0

Point 1 [x y z]: 1 0 2

Point 2 [x y z]: 2 0 1

Point 3 [x y z]: 4 0 0

Point 4 [x y z]:

>curveInterpolation

Degree [3]: 3

Select curve points [Press Enter when done]

Point 0 [x y z]: 4 0 0

Point 1 [x y z]: 4 1 0.5

Point 2 [x y z]: 4 3 1

Point 3 [x y z]: 4 4 0

Point 4 [x y z]:

>curveInterpolation

Degree [3]: 3

Select curve points [Press Enter when done]

Point 0 [x y z]: 4 4 0

Point 1 [x y z]: 3 4 0.5

Point 2 [x y z]: 1 4 0

Point 3 [x y z]: 0 4 2

Point 4 [x y z]:

>curveInterpolation

Degree [3]: 3

Select curve points [Press Enter when done]

Point 0 [x y z]: 0 4 2

Point 1 [x y z]: 0 2 1

Point 2 [x y z]: 0 1 0.25

Point 3 [x y z]: 0 0 0

Point 4 [x y z]:

Remember that you need to press Enter when all the points of a curve have been introduced. The result of these curves are shown in the following figure:

Curves used for the coons patch

Now we are going to create the coons surface. To do this, use the coons command:

>coons

Select a closed set of 2, 3 or 4 curves (press Enter when done):

The result is shown in the following figure:

Resulting coons patch

We use cookies on this website to improve your navigation experience on this site. By using this site, you agree to our cookie policy.

I agree