Mesh/Mesh Server Weight

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READ THIS FIRST

This is a preliminary design of an unimplemented cost algorithm. EVERYTHING is subject to change, and certainly will change, during the course of implementation.

Motivation

The server must track all pieces, or prims, in the region at all times. As such every individual piece, or prim, has a certain cost to the server regardless of its physical or visual complexity. There are, however, some factors that make an object more or less expensive for the server to track: in particular truly passive objects that are not scripted or physical are much easier to track than scripted or physical objects.

Concept

There are two basic goals for this cost:

• The maximum server load from objects should not increase from mesh content.
• Allow more passive content than before.

Equation

Important: This section is out of date and needs an edit. The revised formula is MIN{ (0.5 * num_prims) + (0.25 * (num_scripts - (num_scripts > 0))), num_prims }

1. Take the number of prims in the object.
2. If the object contains no scripts and is not physical: divide by static_bonus

• per_prim_cost = 1.0
  
• static_bonus = 2.0
  
• cost_scalar = 1.0

The static_bonus only applies if the object is not physical and contains no scripts.

Server weight per prim: cost_scalar * (per_prim_cost / static_bonus)

Examples

Prims	Scripted Or Physical	Server Cost	Non-Mesh Cost
1	No	1	1
1	Yes	1	1
10	No	5	10
10	Yes	10	10
30	No	15	30
30	Yes	30	30

How To Optimize

• Consolidate mesh shapes such that the individual uploaded meshes are as complete as possible.
  • A more complete mesh will generally have a streaming cost of several PE and not be server bound.
• Separate static content from dynamic content when possible.