Curved Segment using GDL Primitive Elements

[Nader Belal]

Hi everyone,

Can someone explain me how to create curved arcs and surfaces using VERT, VERT{2}, TEVE, EDGE, & PGON ??

I tried searching for an example to follow, but I couldn't find any.

[runxel]

Okay, great, always love to discover new methods!

I'm really eager to know how you achieve this.

[leceta]

same here, I still need to see this with my eyes. A simple example should be enough to show the implementation... How are you defining curves using vertices, edges and polygons (and apparently not being able to use status codes on corresponding commands)? Very curious...

[Nader Belal]

Alright, I will make two posts and share it here

[Nader Belal]

Buy the way, I'm half way through

[Nader Belal]

By the way, I´m half way through

[Peter Baksa]

All GDL commands will get translated to these primitives by AC. Curved surfaces just have many small polygons.

Here is some help for using TEVE: http://gdl.graphisoft.com/gdl-style-guide/script-type-dependent-recommendations

I'd recommend using BPRISM_ and COOR{3}  for a curved panel btw.

[leceta]

Thanks Peter, I understand this, its like many other platforms, rhino for example, where one can define nurbs surfaces (mathematically continuous) but still are represented (and only represented) as meshes (discrete representations). Further operations on that surface still are on the nurbs, though.
My surprise was in relation to the aim of defining "curves" or "curved surfaces" through a discrete system, which "is" (or "seems", afaik) an oxymoron.
In a private conversation, if I understood him correctly, Nader was trying to obtain a smooth representation of a discrete surface, which is all about shaders (well, and in the case of GDL applying the appropriate status code to de edges/polygons.

[SenecaDesignLLC]

My poly tube calculates the positioning of the materials along curve sections for this exact purpose in terms of like a wood curved railing so that you can get a consistent wood grain all the way up the curve One of the things I hate about ArchiCADs railing tool

[SenecaDesignLLC]

https://youtu.be/3WW5X7Q8FIc

[leceta]

thank for the video seneca, really great job!
But for the sake of clarity in relation to the post, let me comment that your particular example is more related to texture UV mapping (TEVE, I suppose) than shading (which happens to be related to vertex normals). Correct me if I'm wrong.

bests, Aitor