Trying to make a oloid, giving me this problem

Grasshopper
,
1

Hello everyone, I am new to python in rhino and I am having this problem of the image.

2023-06-02_16-06-52
2023-06-02_16-06-521916×824 222 KB

Code:

import Rhino.Geometry as rg
import math

u_values = rg.Interval(0, 2 * math.pi).DivideByCount(100, True)
v_values = rg.Interval(0, 2 * math.pi).DivideByCount(100, True)

points = []

for u in u_values:
    for v in v_values:
        x = math.cos(u) * math.sin(v)
        y = math.sin(u) * math.sin(v)
        z = math.cos(v)
        point = rg.Point3d(x, y, z)
        points.append(point)

mesh = rg.Mesh()
mesh.Vertices.AddVertices(points)

a = mesh
2

Moved to Grasshopper category.

3

sorry!

4

I just wanted to be sure your question was seen by the right people.

2 Likes
5

If ‘u_values’ and ‘v_values’ are your inputs, why do you immediately ignore and override them?

The error message is crystal clear to me. :question:

import Rhino.Geometry as rg
import math

u_values = rg.Interval(0, 2 * math.pi).DivideByCount(100, True)
v_values = rg.Interval(0, 2 * math.pi).DivideByCount(100, True)

points = []

for u in u_values:
    for v in v_values:
        x = math.cos(u) * math.sin(v)
        y = math.sin(u) * math.sin(v)
        z = math.cos(v)
        point = rg.Point3d(x, y, z)
        points.append(point)

mesh = rg.Mesh()
mesh.Vertices.AddVertices(points)
a = mesh

3. Attach minimal versions of all the relevant files

6

sorry, i don’t know where i override it.

For me it was defining the interval so i get the points and then seting values to position on the formula between the interval.

7

At the beginning. These two lines ignore and override any input values::

u_values = rg.Interval(0, 2 * math.pi).DivideByCount(100, True)
v_values = rg.Interval(0, 2 * math.pi).DivideByCount(100, True)
8

i thought it defined the circle region and divide it with 100 points… so you are saying that I should erase this two command lines?

9

What circle region? Is that hidden in the GH file you didn’t bother to post?

Have you ever read this page? RECOMMENDED! But too late for me now, I’m done.

10

The error message is clear

'interval' object has no attribute 'DivideByCount'

DivideByCount used with curves

image

11

GH didn’t have nothing besides the script.

u_values = rg.Interval(0, 2 * math.pi).DivideByCount(100, True)
v_values = rg.Interval(0, 2 * math.pi).DivideByCount(100, True)

i was meaning this part right here.

12

which command should I use to divide by the count if this one is for curves?

13

What do you want to do?

14

a oloid surface

15

I looked at this image from Wikipedia:

oloid_2023Jun3a2
oloid_2023Jun3a2737×483 29.5 KB

Then tried a few different things and finally settled on creating 1/4 of an Oloid (white group) and mirroring it twice to get a “Closed Brep” (cyan group). I replaced EdgeSrf with NetSrf because it looked better when baked.

oloid_2023Jun3a
oloid_2023Jun3a1835×749 264 KB

oloid_2023Jun3a.gh (23.3 KB)

P.S. Rotated 30 degrees (yellow group) to rest on the XY ground plane:

oloid_2023Jun3a3
oloid_2023Jun3a3854×772 64.2 KB

Some rendering artifacts are still visible using NetSrf… :thinking:

2 Likes
16

Check this, create a parametric oloid shape

image
image1172×631 131 KB

To calculate the angle a at tangent point to draw the arcs

image
image1172×597 52.4 KB

oloid shape.gh (20.1 KB)

1 Like
17

Hi ，You can generate the list like this.

count = 100
list = rs.frange(0, 2 * math.pi,2 * math.pi/(count-1))
1 Like