Land Impact

[Akiko Manamiko]

Hello

I have a larg house 55 m to 25 m and 3 floors mad of 300 prims. I like to change the objects from prims to convex hull in order to reduce land impact. Should i link all prims in one step together? Or is it better to link only smaller parts, e.g. each side separate? Does it matter if i link them complex, in 2 or 3 steps, or should i link them in one step?

Kind regards Akiko

Thank you for the quick respose. I just would link cubes, no objects with scrips, no doors, stairs etc. (i already needed a rollback of my sim :( ) I could find the current size limit of linked objects, so my main question is: should i link smaller or bigger parts and in one step or encapsulated. 

 

 

 

[Rolig Loon]

That's a very hard question to answer because it depends on too many variables.  First of all, is it even possible to link all the prims together, or are they too far apart to be linkable in a single linkset? Then how many of those prims are scripted, and how many of those depend on NOT being linked?  Some doors must not be linked to anything else.  Others must be linked to each other but not to the house. Same with windows, curtains, lights, security systems, and many other things.

Then, what kind of prims are in the house?  When you turn a basic prim (a cube, cylinder, sphere... ) from Physicis Shape Type prim to convex hull, its L.I. drops by 50%.   If you do the same thing to a torus or to a sculpty, the land impact can explode by several hundred times.  The immediate result would be that you'd be over your prim allowance and the servers would return the excess to your Lost & Found. So, even if you linked the parts of your house, turning them convex hull might be a bad idea.

The bottom line is that you are on the safest ground if you built the house and scripted all of its parts yourself, as I have.  Even then it's easy to forget why you left some things unlinked in the first place.  If you weren't the original builder/scripter, you at least need to be able to assess all the risks.  If you don't feel up to the task, don't do it.  On the other hand ...... if you have a backup copy in inventory so you can recover from a disaster .... :smileywink::smileytongue:

[Lindal Kidd]

Besides Rolig's great advice about the fine points of linking objects, you should be aware of what the physics type does to the behavior of objects.

Let's say you have a door frame, made out of a hollowed rectangular prim.  If the physics type is "prim", then you can pass through the hollowed out hole.  But if you change the physics type to "convex hull", then the system treats your prim as if it did not have a hole in it.  If you try to walk through the door, you'll bump your nose.

This can be very problematical if your house's walls are, say, three sides of a hollowed out box.  The whole thing behaves like the original big cube and won't let you inside at all.

Convex Hull saves a ton of land impact if used correctly, but it's not quite an automatic magic wand.