Objects on surface

[AlexGross]

Dear all,

I made a vase that looks like this (thanks to all who helped in my previous threads):

Screenshot from 2022-04-08 11-46-06.png (22.4 KiB) Viewed 1335 times

Now I want to add spheres, which are spread on certain positions ON this surface. What I did so far is to simply add a sphere (PartWB), double click on the sphere, activate "3D view" and then I can place it anywhere on the surface. However, it obviously choses the center of the sphere to lie on the surface. Is there a way to make the sphere only touch the surface? So it doesnt lie half-in the surface?

I am able to get this:

Screenshot from 2022-04-08 12-00-48.png (54.78 KiB) Viewed 1335 times

What I want is this (here I manually moved each sphere to different directions (x,y,z), so that they touch the surface):
How can I do this?

Screenshot from 2022-04-08 12-01-46.png (58.43 KiB) Viewed 1335 times

[AlexGross]

One way I came up is to first put all the balls on the surface with the method described. And then make a 3D offset of the vase with negative values equal to the radius of the balls...
But this only works if all balls have the same radius (which in my project they wont)

[chrisb]

It depends on the sketch. If it doesn't have B-splines, then you can attach something to the sketch. You may also try to attach something tangential to the surface (didn't try myself with a shell).

[drmacro]

Looks a lot like what happens in this video:

https://youtu.be/UZnlKQpV85I

[Bance]

For attaching tangentially to a surface, one needs a surface and a vertex to fully define the attachment.

I used the curves WB to discretise one of the 'Revolve' curves > Part wb revolve this (Series of points) and then back to Curves WB to descretise the revolved points. This produces a grid of points for attachment purposes, unfortunately it not possible to select all curves at once they have to be done individually .

After the first descretise operation change the number of points in the data tab to something more reasonable (I used 10.)

When attaching the spheres use a function = Radius for the Z offset, this makes the spheres tangential (since the origin is the centre) and parametric.

YMMV, Steve.

vase.png (67.13 KiB) Viewed 1194 times

[AlexGross]

Looks a lot like what happens in this video:

https://youtu.be/UZnlKQpV85I

Indeed, that looks very nice. Do you by chance know if there is an option to place a random lattice on a surface?

[drmacro]

Looks a lot like what happens in this video:

https://youtu.be/UZnlKQpV85I

Indeed, that looks very nice. Do you by chance know if there is an option to place a random lattice on a surface?

You can single paper planes anywhere you like. There are also arrays that allow random placement in the span for both linear and polar lattice arrays. (I have not experimented with either...)

[AlexGross]

Looks a lot like what happens in this video:

https://youtu.be/UZnlKQpV85I

Indeed, that looks very nice. Do you by chance know if there is an option to place a random lattice on a surface?

You can single paper planes anywhere you like. There are also arrays that allow random placement in the span for both linear and polar lattice arrays. (I have not experimented with either...)

Thank you this are great news. Do you know if it is possible to put a plane on the surface and perpendicular to the surface? Why do you have to manually move the paper plane and rotate it so that it is under surface and perpendicular to it?

[drmacro]

...Thank you this are great news. Do you know if it is possible to put a plane on the surface and perpendicular to the surface? Why do you have to manually move the paper plane and rotate it so that it is under surface and perpendicular to it?

That's a question for @DeepSOIC

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[edwilliams16]

Thank you this are great news. Do you know if it is possible to put a plane on the surface and perpendicular to the surface? Why do you have to manually move the paper plane and rotate it so that it is under surface and perpendicular to it?

I don't recall MangoJelly doing it by hand. I think he approximated his b-spline by a circular arc and projected a polar array on the arc onto the b-spline.
You could use a series of arcs and append the placement arrays if necessary. I'll be surprised if random doesn't prove difficult and you might not like the result - probably too clumpy.