(HELP) how to create solid from 3 planar surfaces


I am learning how to model rocks and other non architectural elements around the garden.
I followed this vid: https://vimeo.com/85506062

But is interrupted, or maybe too simple…but once i get the 3 surfaces, I don´t know how to make de rock solid.

I tested some solid commands, create solid no, sweep surfaces, etc.

Could you help me please?



hey i believe this is only for far distant objects for decoy decoration. but actually its possible to create a solid out of those already prepared polylines pretty simple.

see that 4 polylines or curves meet each other at those 2 points

then use loft, check closed loft with straight section style or usual loft
you will see which one suits more.

then mesh it and use ReduceMesh to get more facets into it.
oh and use FlatShade to deactivate the phong smoothing.

generally you can start from a revolved object move the points a bit and do the same mesh ReduceMesh procedure.

forgot to add by using the command smooth you can then also compact the stone like object so that long edges get also equalised.

Thank you very much for your answer. I´m trying, step by step to understand Rhino logic. :slight_smile:

for such an arbitrary/random object you’re better off using Blender.

If you prefer doing that in Rhino, create a surface (patch) from one of the closed polylines and simply drag its control points to get the form you desire.

i am not sure why you suggest that. rhino has equally sufficient options to create such objects, there are many methods. blender will not offer more, rather the opposite.

Because Rhino is an engineering tool above all.
As such, for CGI I consider it an overkill.

In Rhino to create such a rock you need to first draw the profile polylines, then extrude them, then trim them, then join them. One mistake and wrong accuracy set and you may spent hours to split and join to make it a closed solid.

In Blender you start with a box subdivide it multiple times and then all you need to do is drag the control points to match all profiles(pictures). You can even make it rougher as in Blender you can pull edges (functionality that may be possible in Rhino7 :crossed_fingers: ). You can make the rock hairy if you extrude points. You can’t do this in Rhino (to my knowledge).

Oh yes, and there are different modifiers in Blender that will make your job much easier. And all this will take you (for this rock) from 15 min to 1 h with painting the texture and rendering :slight_smile:

hehe, i believe i saw a plugin called rhino hair somewhere. other than that its just pipes or curves arrayed onto a surface anyway meaning they are normal to it so no magic. dynamic hair would need kangaroo, but i personally also would that with a third party but only because i do not use kangaroo that much yet. so many things to do…

You can do that in Rhino 6 (and in Rhino 5).

in my job Kangaroo is simply useless and too much of randomness. For sure an overkill when talking about CGI.

That’s kinda it, you need too many plugins for Rhino to do it properly because it’s an engineering and not a CGI tool. Whilst Blender is dedicated for CGI and kinda useless for engineering.

Not really. Not like Blender at least. From the top of my head, you need to select a row/column of control points in order to manipulate a surface like this. You can’t really group control points so that’s a bust. if you want the same effect you need to grab the bordering control points of two alligned edges of the surfaces and drag them all. Not pretty!

@wim SUBD is stil not in Rhino6, am I right?

You don’t need control points to pull an edge in Rhino 5:

As for SubD in Rhino 6 - there’s still ToSubD (previously known as SubDFromMesh)

@wim is that mesh or surface-solid?

That’s a NURBS object.
but the same goes for a mesh object.

Could you show a video which command you use and if this object is joint-solid and not single surfaces?

The object is a simple box that is arrayed 4 × 4 × 4 and boolean union’ed into one single object.
There are no commands used to pull the ege - I used the gumball but you could use the Move command.
The only “trick” is that you need to use sub-object selection to select the edge - i.e. Ctrl + Shift+LMB.

Well then you’re cheating. Pull the Iso curves like that then I’d say you prove you can do this in Rhino.

Well, then you are also cheating in Blender, I suppose. You’re not pulling isocurves there either.

True. But you don’t need to duplicate an object in order to get to a point to be able to drag edges. :slight_smile:

One button and roll of the scroller of the mouse and you’re there :stuck_out_tongue_winking_eye:

(to clarify, I’m not Blender regular user I used it a few times when using Rhino was too much effort)

i belive a closer description of that might help the rhino developers distinguishing what needs to be done to enhance the usability or even the functions itself.

They don’t need to do anything, I do not consider Rhino being superior (or usefull for that matter) for CGI when you have Blender (free open-source and cPython scriptable).