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Why are there no "odd" torus primitives? - Printable Version

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Why are there no "odd" torus primitives? - Magnus Forsberg - 2013-07-30

Lately I've been making a lot of minifig heads and I'm missing a primitive I would like to use. A 3/16-sided torus primitive.

Then why don't you just make one, I hear? It seems to be impossible to give it a correct name!!
Why is it impossible to give name to a torus with odd number of faces?

It is not impossible to make one. I've attached an example here. Why??


Re: Why are there no "odd" torus primitives? - Chris Dee - 2013-07-30

The naming convention was devised at a time when we were constrained by 8.3 filenames and wee needed four characters to specify the ratio to sufficient precision.
[quote Primitives reference]
tfforrrr.dat (The second and third characters of the filename ff denotes the sweep of torus, as an inverse fraction (01=1/1, 02=1/2, 04=1/4, 08=1/8, 16=1/16, 32=1/32, 48=1/48)).[/quote]

I don't think it is too great an overhead to use t08o6250 + t16o6250 to build a 3/16 torus.


Re: Why are there no "odd" torus primitives? - Magnus Forsberg - 2013-07-31

No it isn't, but it forces me to rotate them, with subsequent rounding errors...;-(


Re: Why are there no "odd" torus primitives? - Bernd Broich - 2013-08-10

why we couldn't use "t03" for it? "t05" for 5/16 and so on? The primitive generator uses "t99" for non standard ones.


Re: Why are there no "odd" torus primitives? - Travis Cobbs - 2013-08-12

Any model using torus files with such names would not display correctly in LDView with primitive substitution enabled, because primitive substitution there parses the filename and has expectations based on the spec. In other words, the spec says that the first two numbers after the t represent the denominator of a 1/x expression, and LDView behaves accordingly.