michael

should i then try making sphere using sweep and trying the same exercise?

thanks

""""""""""The only drawback I notice when playing with MOi3D is the viewport speed.
When I start filleting objects the frame rate drops badly."""""""""

Rememebr that MoI is a NURBS modeler and you are making comparison to Polygon modeler.. They are different, especially when you start adding Finite detail like little fillets on everything...

In a NURBS Cad modeler comparison, MoI's Viewport blew doors on 15-20,000 dollar software!!!!

It would not be right to call it's viewport slow (Although I do undertsand what you are describing)

Usually, those other high end app's, start to "Cull" the viewport when trying to do any manipulation in it.."culling can be good, if you are starting to work on 1,500 part assembly's, but in everyday workflow, it is a distraction...

FYI.

Hi Mario,

> should i then try making sphere using sweep and
> trying the same exercise?

Yes - if you want to avoid compression at the top dome area of a regular sphere, try making a dome using the sweep technique shown in that previous post and use that as the target surface instead.

That surface does not compress to a pole at the top so it won't have the same kind of compression as a sphere does.

The new problem that you'll have is that you can't make a complete closed sphere shape out of a single surface that way, just sort of a portion of one.

- Michael

>>>>Rememebr that MoI is a NURBS modeler and you are making comparison to Polygon modeler.. They are different, especially when you start adding Finite detail like little fillets on everything...

In a NURBS Cad modeler comparison, MoI's Viewport blew doors on 15-20,000 dollar software!!!!

It would not be right to call it's viewport slow (Although I do undertsand what you are describing)

Usually, those other high end app's, start to "Cull" the viewport when trying to do any manipulation in it.."culling can be good, if you are starting to work on 1,500 part assembly's, but in everyday workflow, it is a distraction...

FYI.<<<<<<



I do not meant to attack Moi :-) I love Moi and the great support and feedback from Michael.
I only had some problems with the viewport speed and I'm not used to that with my current system.
It will be better with the change of the setting as Michael asked me to alter.

And indeed as you said, I'm a Polygon modeler for many many years so I only can used that as reference. :-)
Thanks for the reply any way. :-)

Oeace,
Rich_Art. ;-)

michael

so what is the main difference between two identical spheres

1) created from the solids menue
2) created as sweep to identical dimensions

thanks

Hi Mario,

> so what is the main difference between two identical spheres
>
> 1) created from the solids menue
> 2) created as sweep to identical dimensions

You won't really be able to do a sweep to the exact same shape as a pole, but you can make a sort of dome shape with the sweep.

The easiest way to see the difference is to turn on surface control points with Edit > Show pts.

For a sphere surface you can see that the surface control point grid has "poles" in it and how the control points compress together as they near that pole, like this:



On the other hand, if you create 2 crossing curves like so:



And then use sweep with one of them as the profile and the other as the rail to follow, it will build a type of dome surface like this:



And then if you select this surface and turn on its control points you can see that they are arranged in more of a regular grid pattern and the edges of the grid do not totally collapse down to a single point as a default sphere surface does:




If you want to avoid compression with Flow you'll need to use surfaces that are more like this in their structure - more evenly distributed and not having portions of the surface compress down to a point like a sphere does.

- Michael

michael

i have done few succesful tests using pattern on sphere.
my conclusion is:

if we assume that rectangular extent of the pattern is of 2:1 proportion, then shorter side is projected along equator and longer side is projected along meridian.
can we control this? i have tried rotating pattern and target and it does not seem to have any effect.

thanks for your professionalism and time

mario

>>>>The settings for that are under Options > View > Meshing parameters - try setting "Mesh angle" to 25 degrees and uncheck "Add detail to inflections" and see if your display speed gets a boost.<<<<<


LoL found the problem. The mesh angle was set to 1. instead of the standard 10.

Peace,
Rich_Art. ;-)

Hi Rich_Art,

> LoL found the problem. The mesh angle was set to 1.
> instead of the standard 10.

Yeah that would do it - the default 10 degrees will already generate pretty dense display meshes.

With an angle of 1 degree (that's a max of 1 degree angle between surface normals) it would be generating a really large quantity of teeny tiny little tiny polygons for the display mesh.

With it set back to the default you'll probably see reduced calculation time as well since it would take more time for generating those really dense display meshes, in addition to bogging down the display.

If you start to work with more complex models with a lot of pieces in them, it can help to set the mesh angle to something rougher like 25 degrees to reduce memory consumption of the display meshes.

- Michael

Hi Mario,

> if we assume that rectangular extent of the pattern is of 2:1
> proportion, then shorter side is projected along equator and
> longer side is projected along meridian.

Do you mean that the result is rotated 90 degrees from what you need?


> can we control this? i have tried rotating pattern and target
> and it does not seem to have any effect.

You can control it by manipulating the base plane - if for example the result is rotated by 90 degrees from what you want, that means that one of the surfaces has their U and V directions swapped from what you need.

So to fix that up you need to swap the U and V directions of your base plane - you can do that by rotating it around its diagonal by 180 degrees and then scaling it.

In the next v3 release that won't be necessary anymore since it will automatically swap or reverse any U V directions on the surfaces as necessary to align the corners nearest to which you pick on the surfaces.

But for now manipulating the base plane is how you control it. When you manipulate the base plane you leave the objects you are going to deform alone and just change the plane, don't rotate the whole set of both base plane and objects together - if you do that there will be no change since it's how the objects relate to the base plane that is controlling things.


Basically the way that Flow works is that for every point on the objects that are being deformed it finds the closest point dropped down on to the base plane. That produces a UV coordinate in the UV space of the plane, and an offset distance for how the point is above or below the plane. Then that same UV point is evaluated on the target surface, and the same offset distance is applied.

So basically Flow works by going from the UV space of one surface into the UV space of a different surface.

Every NURBS surface is made up of a rectangular grid of control points, and one direction of the grid is the U direction and the other is the V direction.

- Michael