Rounding Errors in primitives?


RE: Rounding Errors in primitives?
#11
(2021-04-29, 20:54)Magnus Forsberg Wrote: The file claims to be made using PrimGen2, but if I re-create a new version today, I get correct values.

Then it seems like an open and shut case.

I am currently on a MAC without access to PrimGen2. Are you able to generate 1-4ring5.dat and compare it to the official file as well? It also appears to have a mix of computed points. If I compute the primitive in what I believe is the correct way, then I get the point:

5.5434 0 2.2962

such as in the quad:

4 16 6 0 0 5.5434 0 2.2962 4.6195 0 1.9135 5 0 0

which differst from the official file:

4 16 6 0 0 5.5433 0 2.2961 4.6195 0 1.9135 5 0 0

The point should come from scaling the points from the simple primitives. In this case we can take 1-4edge.dat with the point:

0.9239 0 0.3827

Multiply by 6 and you get the "5.5434 0 2.2962" point and not the one in the official file!


Now. If I generate this primitive without regards to the trick, then I get another issue. I get the following quad:

4 16 6 0 0 5.5433 0 2.2961 4.6194 0 1.9134 5 0 0

which ALSO differs from the quad in the official file:

4 16 6 0 0 5.5433 0 2.2961 4.6195 0 1.9135 5 0 0

So how was this primitive generated?
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RE: Rounding Errors in primitives? - by Lasse Deleuran - 2021-04-29, 21:44

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