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Axle primitives incompatibility with HD primitives - Printable Version

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Axle primitives incompatibility with HD primitives - Max Murtazin - 2022-03-23

Recently I have noticed that some axle primitives are incompatible with HD circular primitives. On almost any model using axle primitives have holes show up in some places. Probably, we can introduce series of HD axle primitives that would match the HD circular primitives?
   


RE: Axle primitives incompatibility with HD primitives - N. W. Perry - 2022-03-23

(2022-03-23, 7:43)Max Murtazin Wrote: Recently I have noticed that some axle primitives are incompatible with HD circular primitives. On almost any model using axle primitives have holes show up in some places. Probably, we can introduce series of HD axle primitives that would match the HD circular primitives?

Either that or an adapter ring of some kind. But do the vertices of an axle prim match up with the 1/48th sectors?

Better still, of course, would be the ability to designate any face as being part of a round surface, so that LDraw tools could apply smoothing/prim sub across the board without the need for special LDraw primitives. But that might require a resolution of the vertex normals conversation that has been started and stopped so often…


RE: Axle primitives incompatibility with HD primitives - Max Murtazin - 2022-03-23

(2022-03-23, 14:26)N. W. Perry Wrote: do the vertices of an axle prim match up with the 1/48th sectors?

No, they don't (except for the 4 that match with circular primitives of any resolution).

Btw, I have made set of the high-res axle primitives that fit the high-res circular primitives. Not much would need to be polished about these if it would be decided to add high-res primitives (would be mostly naming and some other minor stuff, like conlines on axlehol8). This includes not all axle primitives, but it's enough for demo of making high-res axle ones is enough for fix of the problem:    


RE: Axle primitives incompatibility with HD primitives - Orion Pobursky - 2022-03-23

A better question is why are we using 48 primitives at axlehole scale?


RE: Axle primitives incompatibility with HD primitives - Max Murtazin - 2022-03-23

(2022-03-23, 15:21)Orion Pobursky Wrote: A better question is why are we using 48 primitives at axlehole scale?

What do you mean?


RE: Axle primitives incompatibility with HD primitives - Orion Pobursky - 2022-03-23

Typically, using 48 segment primitives at the small scale of axleholes is overkill. While there is no formally defined size threshold for switch over to using 48 prims (since it depends on a lot of things including visual look), the normal 16 segment prims are fine for such a small detail level.


RE: Axle primitives incompatibility with HD primitives - Max Murtazin - 2022-03-23

(2022-03-23, 15:34)Orion Pobursky Wrote: Typically, using 48 segment primitives at the small scale of axleholes is overkill. While there is no formally defined size threshold for switch over to using 48 prims (since it depends on a lot of things including visual look), the normal 16 segment prims are fine for such a small detail level.

Oh. The thing is, some software like LDView or Bricklink Studio has an option of substituting 16-primitives for 48-primitives for smoother rendering quality (which is pretty good thing to have in cases when you are making then stuff like lego renders - 16-primitives look a bit too angular with commonly used resolution like 720p, 1080p or higher. 

I originally thought that this is one of intended uses of the 48-primitives, if not then this topic is irrelevant, but I think still that it would've been good to have standardised high-resolution primitives to be universally used in the mentioned cases, and not only for bigger circular/spherical details which require use of 48-primitives to look good


RE: Axle primitives incompatibility with HD primitives - Orion Pobursky - 2022-03-23

(2022-03-23, 15:43)Max Murtazin Wrote: Oh. The thing is, some software like LDView or Bricklink Studio has an option of substituting 16-primitives for 48-primitives for smoother rendering quality (which is pretty good thing to have in cases when you are making then stuff like lego renders - 16-primitives look a bit too angular with commonly used resolution like 720p, 1080p or higher. 

I originally thought that this is one of intended uses of the 48-primitives, if not then this topic is irrelevant, but I think still that it would've been good to have standardised high-resolution primitives to be universally used in the mentioned cases, and not only for bigger circular/spherical details which require use of 48-primitives to look good

Since axleholes are standardized, it would be my expectation for programs that do implement primitive substitution to automatically smooth these primitives to match the cylinder resolution they are substituting to. I believe LDView already does this, Studio probably not. We have added the ering primitives to allow for smooth substitution in those cases where quad/triangle geometry meets round primitives, for the most part proper smoothing and primitive substitution is up to the program developers and is not something we cater to in the library.


RE: Axle primitives incompatibility with HD primitives - Max Murtazin - 2022-03-23

(2022-03-23, 17:45)Orion Pobursky Wrote: Since axleholes are standardized, it would be my expectation for programs that do implement primitive substitution to automatically smooth these primitives to match the cylinder resolution they are substituting to. I believe LDView already does this, Studio probably not. We have added the ering primitives to allow for smooth substitution in those cases where quad/triangle geometry meets round primitives, for the most part proper smoothing and primitive substitution is up to the program developers and is not something we cater to in the library.

Okay, got about that. Is there any guide on using erings? I don't see those listed in primitives list, and mentioned in the description of those prims thread doesn't seem to be very useful for me to understand those


RE: Axle primitives incompatibility with HD primitives - Magnus Forsberg - 2022-03-23

(2022-03-23, 7:43)Max Murtazin Wrote: Recently I have noticed that some axle primitives are incompatible with HD circular primitives. On almost any model using axle primitives have holes show up in some places. Probably, we can introduce series of HD axle primitives that would match the HD circular primitives?

All of the updated axlehole primitives include the ering primitive. You need to update your library.
The part in your image is clearly using the old design. What part is it?