Mixed physical/phantom objects now possible...

[Jenni Darkwatch]

No idea if anyone mentioned this before...

I just noticed that it's now possible to have one linked object with a mix of solid/phantom prims, by setting the physics shape of the desired prims as "None" in the build floater. Just in case anyone finds the info useful :)

My presumption is that the less prims are physical on a sim, the better for the sim. So, this is rather good news for me.

Edit: Forgot to mention: This changes the whole build to "opt-in" to the land impact system... which can be good, or can be bad (as in, increase or decrease the prim count of the object MASSIVELY).

[Kwakkelde Kwak]

You can also keep "some" physics by setting prims to convex hull rather than prim... this closes holes in prims, but in a lot of cases they are only visual anyway... does wonders for the primcount...but as you said..it's an open invitation for 'cheating" the system and I'm not quite sure if I really like the options...

[Jenni Darkwatch]

Depends on the object really. If it has anything like a sculpty in it, the prim count explodes Same with some of the more complex shapes like torii and various tortured prims. Mesh fares well, if it's built well - most are not, at this point in time.

[Kwakkelde Kwak]

That's exactly my point. People will set their boxes to convex hull and not the torus and sculpt rubbish. The result? more prims on every simulator, more lag.

 

EDIT..and if your experience is most meshes are not well built right now that's no good news for the future, since I think it's the better builders picking up on it the soonest. Let's hope I'm wrong and maybe people learn to build better.

Changes in LI in mesh are caused by the physical shape, often it doesn't need one at all. So linked or not linked to anything else shouldn't make a difference for mesh I think. Bad physical numbers for a mesh convex hull have nothing to do with the qualify of the build in the first place. If it's built right, it has its own shape for physics.

[Void Singer]

this has actually been possible for a long time before physics shapes were available, just not for the root prim. Setting volume detect true before linking a prim as a child allows specific prims to be effectively phantom within the linkset. there are cases where this will be a better solution than setting the physics shape.

[Jenni Darkwatch]

I'm admittedly fairly clueless with mesh. My curiosity has been enough to get me to peek at mesh a little bit. Rigged mesh seems to often be ridiculously detailed. More triangles are better, right?

It's kind of the same-old, same-old with mesh: What people wear is exempt from any controls or checks. Because of that, I'm actually not too worried about 15k prims or even 30k prims on land. I'm guilty of that too, since most of my avis use sculpted body parts.

@Void:
Yep, that trick I knew of. I never thought it was a terribly good idea, but that's just me. Too often creators left the "phantom script" in the build. One of many pet peeves of mine

[Void Singer]

I agree, and there are two lesser methods that actually require the script to be left in... I have used it with some success in builds though... the prims that act as tiedowns for my airship use this trick to great effect, although I haven't gotten around to checking if I could lower the anchorages PE with physics instead (I kinda like having the tie down stakes physical)

[Kwakkelde Kwak]

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Void Singer wrote:

[...] Setting volume detect true before linking a prim as a child allows specific prims to be effectively phantom within the linkset. there are cases where this will be a better solution than setting the physics shape.

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That makes me curious...When would that be a better solution?

[Void Singer]

when it results in a lower PE than using physics shape.... which is dependent on the build.

[Kwakkelde Kwak]

Same question:) ...can you give an example?

I tried a very simple setup, two linked boxes. If I add the VolumeDetect script to the child prim (and take it out again) the Landimpact is still 2 for the set. This is until the child prim physics are set to "none", then the impact is 1. It's a simple test, I know, but I can't see how the VolumeDetect will ever lower the primcount more than a prim with no physics.

[Void Singer]

depending on the build you won't be setting all child prims to no physics. in some case people are reporting that setting only one or two children to use physics accounting (eve physics:none) increases the PE above the prim count. in the more complex case you may have linked meshs or children using something besides default physics shapes.... the volume detect hack will never lower PE below prim count, but may prevent raising it in situations where mixed physics might lead to a rise using just a physics:none shape on that prim.

experimenting with torii or cut shapes might be the place to find where that makes the most difference

[Kwakkelde Kwak]

completely forgot "your" way keeps the "old" way of primcount intact..very true, no test needed, thanks for pointing that out...

collision prims for sculpts, things like that, would result in big big numbers with the "new" way.

[Void Singer]

heh I wish I could take credit for that lil hack

[DanielWildcat]

For some reason several models i have imported seem to be physical for some and phantom for others _at the same time_  anyone know why?

 

http://i.imgur.com/L9FLDry.png

 

I.E. one person is able to stand on an object that another avatar cannot. (falls right through)