Grasshopper

generative modeling for Rhino

# point and sphere :)

Hi, I'm trying to build a control point on the

Views: 384

### Replies to This Discussion

hi alex, i don't understand the question would you expand it a bit. maybe include a sketch or a file please.

1,1,1 is the point on the sphere ?!

Attachments:

I can not understand why the point x = 1, y = 1, z = 1 (point2.bmp)
outside the sphere?

Attachments:

Why would it be inside?

a point at 1,1,1 is about 1.73 units away from 0,0,0. Since 1.73 > sphere radius of 1, it is outside the sphere.

Points like:

0,0,1

0,1,0

1,0,0

Are all inside the sphere (or rather on the sphere, not sure if that counts).

they are in sphere surface domain :P

thanks Brian for the help, but 1,1,1 is the point on the sphere

the point x = 1, y = 1, z = 1 is neither inside nor on a sphere with an origin of 0,0,0 and a radius of 1. What is it that you are trying to do?

put a point 1,1,1 on the sphere

you can do a variety of things to put a point on a sphere, but you can never have a point at 1,1,1 be on a sphere with a radius of 1 at origin 0,0,0.

You could:

Use brep closest point to find the closest point on the sphere to 1,1,1

draw a line from the origin to 1,1,1 and intersect it with the sphere

use the evaluate surface component to create one or more points on the sphere

etc.

I'm trying to read between the lines here... maybe you want to create a point from x,y,and z values that creates a sphere with a radius equal to the distance between 0 and the point? like so:

Brian, thank you for this example (BRep ). This elegant and beautiful solution. Thank you for your help.

• View All