INonSharedRegion Module - ability to control flocks of prims within an OpenSim scene

To build from source

Add OpenSimBirds source tree under opensim/addon-modules

./runprebuild.sh against opensim root to build this module into the solution then xbuild, or build within Visual Studio / Monodevelop to produce the binaries

OpenSimBirds has no external dependencies other than the dlls currently included in opensim. The project generates a single dll - OpenSimBirds.Modules.dll which is copied into opensim/bin as part of the build step

Configuration

To become active, the module needs enabled in the ini file. Otherwise it does nothing on startup. If you are running multiple regions on one simulator you can have different Birds settings per region in the configuration file, in the exact same way you can customize per Region setting in Regions.ini

The configuration file for this module is in:

addon-modules/OpenSimBirds/config/OpenSimBirds.ini

and follows the same format as a Regions.ini file, where you specify setting for each region using the [Region Name] section heading.

Here is an example config:

;; Set the Birds settings per named region

[Test Region 1]

	BirdsEnabled = True         ;set to false to disable the module in this region	
	BirdsFlockSize = 100        ;the number of birds to flock
	BirdsMaxSpeed = 3           ;how far each bird can travel per update
	BirdsMaxForce = 0.25        ;the maximum acceleration allowed to the current velocity of the bird
	BirdsNeighbourDistance = 25 ;max distance for other birds to be considered in the same flock as us
	BirdsDesiredSeparation = 20 ;how far away from other birds we would like to stay
	BirdsTolerance = 5          ;how close to the edges of things can we get without being worried
	BirdsBorderSize = 5         ;how close to the edge of a region can we get?
	BirdsMaxHeight = 256        ;how high are we allowed to flock
	BirdsPrim = seagull01       ;By default the module will create a flock of plain wooden spheres, 
	                            ;however this can be overridden to the name of an existing prim that
	                            ;needs to already exist in the scene - i.e. be rezzed in the region.	

Various runtime commands control the flocking module behaviour - described below. These can either be invoked from the Console or in world by directing them to a chat channel. To specify which channel to use:

chat-channel = 118 	the chat channel to listen for Bird commands on

Runtime Commands

The following commands, which can either be issued on the Console, or via a chat channel in-world, control the behaviour of the flock at runtime

flock-stop or /118 stop                       ;stop all flocking and remove birds from the region
flock-start or /118 start                     ;start the flocking simulation
flock-size <num> or /118 size <num>	          ;change the size of the flock
flock-prim <name> or /118 prim <name>	        ;change the bird prim to one already rezzed in the scene
flock-framerate <num> or /118 framerate <num> ;only update the flock positions every <num> frames
                                              ;only really useful for photography and debugging bird
                                              ;behaviour

Bird prims

Any currently rezzed in-scene-object can be used as the bird prim. However fps is very much affected by the complexity of the entity to use. It is easier to throw a single prim (or sculpty) around the scene than it is to throw the constituent parts of a 200 linked prim dragon.

Tests show that <= 500 single prims can be flocked effectively - depending on system and network However maybe <= 300 simple linksets can perform as well.

I intend to allow inventory items and UUIDs to represent the birds - this is not written yet however.

Please Note

This module is currently only tested against opensim master. If it is found to work against a stable release, then that behaviour ought to be considered as a bug - which I will attempt to fix in the next git push.

Next Steps

I want to improve the ability of the birds to avoid obstacles within the scene. Current avoidance is pretty basic, and only functions correctly about fifty percent of the time. Need to improve this without increasing computational cost.

Licence: all files released under a BSD licence If you have any question please contact Jak Daniels, jak@ateb.co.uk