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  New primitives?
 
In addition to the unit capped cylinder I suggested here (URL) I'd also like to see some truncated disc and ndis primitives, like the red ones shown below (the truncated disc can also be seen as a half chrd primitive). (URL) This would help building (...) (16 years ago, 26-Mar-08, to lugnet.cad, FTX)
 
  Re: New primitives?
 
(...) First of all, I like the idea of a unit capped cylinder. The stud could then be changed to a reference to the new primitive. We could use x-ycylc as the filenames and call the primitive Cylinder Capped. This would be consistent with the (...) (16 years ago, 26-Mar-08, to lugnet.cad, FTX)
 
  Re: New primitives?
 
(...) OK, so I'll make this primitive, but which way should it face? Should it face up, like the stud primitive, or should it face down, like the box primitives? --Travis (16 years ago, 26-Mar-08, to lugnet.cad, FTX)
 
  Re: New primitives?
 
(...) Oh, and should the cap be at Y=0, or should the base be at Y=0? (For reference, with the stud primitive, the base is at Y=0.) --Travis (16 years ago, 26-Mar-08, to lugnet.cad, FTX)
 
  Re: New primitives?
 
(...) Please let me have some example where they are useful. I found during authoring parts that, just for rounded parts, you would need lots of such truncated primitives, but they would need to be truncated anywhere and not only the way this new (...) (16 years ago, 26-Mar-08, to lugnet.cad, FTX)
 
  Re: New primitives?
 
(...) One concern about capped cylinders is that they would lead more multiples of cylinders - single-capped cylinders, double-capped cylinders, 1/4 capped cylinders, 2/4 capped cylinders, Hi-res 3/8 double-capped cylinders, etc. etc. And every (...) (16 years ago, 26-Mar-08, to lugnet.cad, FTX)
 
  Re: New primitives?
 
(...) A few examples where I would use the 48\1-8tdisc (to use Travis naming suggestion): 58135s01 (rounded sides), 464s01, 54096, 61068 For the 48\1-8tndis (less useful I agree), an example would be 3455. In many case you can stretch a bit the (...) (16 years ago, 26-Mar-08, to lugnet.cad)
 
  Re: New primitives?
 
(...) I would use the cylinder as model, with the cap at Y=0 on top and an edge at bottom. But I somehow agree with Steve Bliss that it may be overkill if we decline capped cylinder in all angles... Philo (16 years ago, 26-Mar-08, to lugnet.cad, FTX)
 
  Re: New primitives?
 
(...) I think I can follow your thoughts. Have you tried that (48/1-8tdisc) already in some items with different curvatures? If yes and you have found out that this can also be used without dramatically mathematics (I prefer to use triangles so I (...) (16 years ago, 26-Mar-08, to lugnet.cad)
 
  Re: New primitives?
 
(...) I agree with you in all points. But if I see that also you are thinking that capped cylinders are useful maybe there is somebody out who can write a prog for that. I have tried something similar in the past and was not very happy with the (...) (16 years ago, 26-Mar-08, to lugnet.cad, FTX)
 
  Re: New primitives?
 
(...) Mathematics to use 1-8tdisk is easy, divide the width by 0.707 and height by 0.293 (1-(sqrt(2)/2) to get size of the tdisk. Move the center accordingly. Yes I have used that trick several times, using regular disc/ndis primitives, inlining (...) (16 years ago, 27-Mar-08, to lugnet.cad)
 
  Re: New primitives?
 
(...) There are already circle chord and tangent primitives on the parts tracker. You would just need to add a couple of triangles to get the ones you're proposing. See: (2 URLs) (16 years ago, 30-Mar-08, to lugnet.cad, FTX)
 
  Re: New primitives?
 
(...) I wasn't aware of the tang primitive, and I had forgotten about the chrd primitive. Going from the chrd primitive to the proposed truncated disc requires the addition of one triangle, and the total number of triangles after adding that one is (...) (16 years ago, 30-Mar-08, to lugnet.cad, FTX)
 
  Re: New primitives?
 
(...) Andrew you are completely right. I was kind of obsessed by the missing triangle so I didn't thought well... I'm a little bit less convinced by the tang primitive that need several adaptation triangles (is it really better than to match (...) (16 years ago, 31-Mar-08, to lugnet.cad)

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