Sort Primitives specific control

[CinnamonMetal]

I want to sort a set of primitives as seen in the image ?

[konstantin magnus]

Sort radially and by distance, then add your results. In a primwrangle:

f@radial = atan2(@P.x, @P.z);
f@dist = length(@P);

@sort = @dist + @radial * 0.01;

Afterwards set the sort node to primitives, "by attribute" and "sort".

Edited March 29, 2018 by konstantin magnus

[CinnamonMetal]

Thanks @konstantin magnus, although I know the image I originally posted is sorta identical to this new image posted.  I want to have complete control over the primitive number. Although the only way I know is if the object is modeled primitive by primitive as we are all familiar with.

[StepbyStepVFX]

You can try using the method described above, but with the UVs attribute (promoted) instead of position... provided you lays the uv correctly (ie. that once unfold, you can use the method above)

[CinnamonMetal]

What do you mean by, promoted ? I thought of the same although wondered how UV would sort primitives ? 

[StepbyStepVFX]

I was meaning using Attribute Promote :

UVProject, vertices and polar mode

UV Transform to center your UVs on the primitve you want as center (prim 0)

Attribute Promote from original class Vertex to New class Primitive, with Promotion method = Average

Then Primitive Wrangle as explained above :

@uv.z = 0;
f@radial = atan2(@uv.x, @uv.y);
f@dist = length(@uv);

@sort = @dist + @radial * 0.01;

Sort node, Primitive, By Attribute, put sort as attribute.

I tried but not convinced by the result so far :-) But check if that's fine for you... I think you'll have to work on a sort attribute made with a wrangle node setup on Detail (run once) and "navigate" your geometry in an intelligent way... (I did something once to determine symetrical topology :

 

Maybe you can do something similar to "sort" your primitives by navigating in spiral around a point : you start at point 0, then finds all primitives to whom this point belong to, you "sort" them by incrementing a sort variable, once all have this attribute value, you find the adjacent primitves starting by the first allocated, and "sort" them, etc. until you "visited" all primitives (so you'll need an array storing all prim number of visitited primitives). I think that's not to hard, but maybe long to write :-)

[CinnamonMetal]

Quote

Maybe you can do something similar to "sort" your primitives by navigating in spiral around a point : you start at point 0, then finds all primitives to whom this point belong to, you "sort" them by incrementing a sort variable, once all have this attribute value, you find the adjacent primitves starting by the first allocated, and "sort" them, etc. until you "visited" all primitives (so you'll need an array storing all prim number of visitited primitives). I think that's not to hard, but maybe long to write :-)

I was thinking about something similar but how do I associate which primitives the point belongs too ? Although I was thinking picking a primitive using that as 0 then it spirals out organized as; 1,2,3,4 etc.

Unless I find the nearest primitive of the next primitive and so that sorts the primitive in a organized number method (1,2,3,4 etc).