- the cone center is C: (3 x 1)
- coneangle is the cone angle (0 to pi, pi corresponds to the extreme case where the cone takes the whole space)
- the cone axis is N: (3 x 1), oriented toward the direction you consider to be in
- Point P: (3 x 1) the point coordinates to be check

# I want to find out points whose coordinates are within the volume formed by a cone shape.

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Hello,

I have plotted few points in a 3D volume as shown in the figure below:

I want to plot a 3D righ Cone from a few specefic points as shown:

These cones are 3D volumes and I want to find out points whose coordinates are within each cone. for example which point is within yello cone and which one in red and which one in purple cone.

Can some one help?

##### 0 Comments

### Accepted Answer

Bruno Luong
on 28 Apr 2022

Edited: Bruno Luong
on 28 Apr 2022

Assuming

Check inside the half of the cone is

dot(P-C, N) >= cos(coneangle/2) * norm(N) * norm(P-C)

You can compute once

cos(coneangle/2) * norm(N)

if you have many points P to check.

##### 3 Comments

Bruno Luong
on 28 Apr 2022

Edited: Bruno Luong
on 28 Apr 2022

The above code plots one part of the surface of the cone truncated at base hight = h, base radius r.

Why? Because the author wants it that way.

### More Answers (1)

Matt J
on 27 Apr 2022

##### 4 Comments

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