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Proposal of new primitives - Massimo Maso - 2021-07-12

I propose the introduction of these six primitives (3 version 16 sides and 3 version 48 sides) that could solve some situations.
The example I have attached is the one with which I came up with the idea, in fact the most correct use would be for patterns with incomplete rings of different colors.
The primitives I propose come from the classic ndis to which, however, I moved the vertex of the circumscribed square to bring it to the vertical of the last vertex of the circle.

They should be quite interchangeable with the current tang primitives, but reducing the number of triangles required (partly because they are already included in the primitives and partly because their shape is more regular).


RE: Proposal of new primitives - Willy Tschager - 2021-07-13

(2021-07-12, 22:19)Massimo Maso Wrote: I propose the introduction of these six primitives (3 version 16 sides and 3 version 48 sides) that could solve some situations.
The example I have attached is the one with which I came up with the idea, in fact the most correct use would be for patterns with incomplete rings of different colors.
The primitives I propose come from the classic ndis to which, however, I moved the vertex of the circumscribed square to bring it to the vertical of the last vertex of the circle.

They should be quite interchangeable with the current tang primitives, but reducing the number of triangles required (partly because they are already included in the primitives and partly because their shape is more regular).

It would help if you add also a thumbnail to have a general idea before downloading the prims.

w.


RE: Proposal of new primitives - Philippe Hurbain - 2021-07-13

(2021-07-12, 22:19)Massimo Maso Wrote: I propose the introduction of these six primitives (3 version 16 sides and 3 version 48 sides) that could solve some situations.
The example I have attached is the one with which I came up with the idea, in fact the most correct use would be for patterns with incomplete rings of different colors.
The primitives I propose come from the classic ndis to which, however, I moved the vertex of the circumscribed square to bring it to the vertical of the last vertex of the circle.

They should be quite interchangeable with the current tang primitives, but reducing the number of triangles required (partly because they are already included in the primitives and partly because their shape is more regular).
Not against it - actually I proposed that when I was a baby parts author a long time ago (Lugnet era...) but tang primitives was said to do the job then. Note that there are many more 48-sided such primitives that make sense (eg. 1-24 or 7-48)!


RE: Proposal of new primitives - Massimo Maso - 2021-07-13

Attached is the image with the comparison of the primitives.


RE: Proposal of new primitives - Travis Cobbs - 2021-07-14

(2021-07-13, 22:00)Massimo Maso Wrote: Attached is the image with the comparison of the primitives.

Would it be agreed that these would all be less than 1/4 circles? In other words, these three, plus the extra 48 ones would be the only possibilities? (I ask because it's unclear what something like 11/16 would look like.)

On the 48 front, the other possible ones would then be:
  • 1-48
  • 1-24 (2/48)
  • 1-12 (4/48)
  • 5-48
  • 7-48
  • 1-6 (8/48)
  • 5-24 (10/48)
  • 11-48



RE: Proposal of new primitives - Massimo Maso - 2021-07-14

Since 1-4tdis would be equal to 1-4ndis, it makes no sense that these primitives exceed 1-4 of a circle. In case you need it, use a normal ndis and tdis for the remaining part.

As for the 48-sided versions, they are useful because they save some lines of code and neighboring but not coincident points for rounding.



In the meantime it occurred to me that the complementary part could already be foreseen (with a lot of imagination I indicated it as tdis2); even if these are already obtainable now with the ndis and adding a triangle would only reduce the number of lines and the possibilities of error.


RE: Proposal of new primitives - Takeshi Takahashi - 2021-07-20

I am for these primitives.

I've found this part Duplo arch u977 has an underside center divider (missing in the part model), and these primitives will fit nicely.
https://www.ldraw.org/cgi-bin/ptdetail.cgi?f=parts/u977.dat


RE: Proposal of new primitives - Philippe Hurbain - 2022-01-16

(2021-07-14, 0:02)Travis Cobbs Wrote: Would it be agreed that these would all be less than 1/4 circles? In other words, these three, plus the extra 48 ones would be the only possibilities? (I ask because it's unclear what something like 11/16 would look like.)

On the 48 front, the other possible ones would then be:
  • 1-48
  • 1-24 (2/48)
  • 1-12 (4/48)
  • 5-48
  • 7-48
  • 1-6 (8/48)
  • 5-24 (10/48)
  • 11-48
Travis, any plan to support these prims in LDView?


RE: Proposal of new primitives - Travis Cobbs - 2022-01-17

(2022-01-16, 16:47)Philippe Hurbain Wrote: Travis, any plan to support these prims in LDView?

I would be willing to support them if they were created and used in parts (unofficial is fine). This thread doesn't appear to have anybody answering the original question, which is whether or not they should be added. I won't preemptively spend the time to support them on the off chance that they might be created at some point in the future (with possibly a completely different name).

Also, I don't understand the proposed name. I'm fine with having 2 appended if we also like the inverse, but I don't know what the "t" stands for. These are effectively ndis primitives that have been cropped to the highest z coordinate along the curve.


RE: Proposal of new primitives - Orion Pobursky - 2022-01-17

Looks like we have 6 tdis currently on the PT they are definitely in use.