In theory, there should be no difference between these mechanisms.
However, on at least Mono 3.2.8 waiting via an event appears to be much more accurate.
This involves making PhysicsActor.PIDActive get as well as set.
On physics components that don't implement this (all characters and some phys engines) we return false.
AvatarFlyingGroundMargin and AvatarFlyingGroundUpForce set to 5.0 and
2.0 respectively which seems to give about the same action as in SL.
Also moved force addition to before the velocity to force computation
so the upward velocity is properly applied to the avatar mass.
This should get around the exception reported in Mantis 7191 and 7204
by checking for the unbuilt child and rebuilding the linkset the next tick.
A warning message is output when this rebuild happens and this message is
clamped to 10 times in case there is a problem with a loop.
For some reason as yet unidentified (feedback?) a threshold above 0.4 here causes the RawVelocity to move between a lower and upper bound rather than remaining constant.
The RawVelocity increased until it triggered the threshold update, at which point it started to decrease until it again triggered the threshhold update.
This delta-v was enough to exceed the checks in ScenePresence.SendTerseUpdateToAllClients() and produce jittery avatar flight because of the fluctuating velocity.
With a threshold of 0.4 (or 0, as with ODE), the RawVelocity remains constant in BulletSim and so avatar flight becomes mostly smooth - remaining occasional glitches appear to be a result of errors in distance extraploation.
There are no obvious problems with commenting out the threshold.
Misterblue, if this is wrong or I've missed some subtlety here, please feel free to revert and/or correct.
The same considerations may or may not apply to object velocity updates.
parameter 'TerrainGroundPlane' which defaults to -500.
BulletSim had assumed altitudes never went negative but that is not true. The
ground plane is just a safety net so things wouldn't fall to infinity.
objects in the world.
This was originally changed in an attempt to make vehicles work better
but the effect was not that large and it causes avatars to float
above the terrain.
a capsule. Set the default to be the rectangle shape and adjust the
parameters in OpenSimDefaults.ini for the new shape.
The rectangle shape will perform better and avatar height can be
computed more accurately.
It originally looked like mesh terrain would perform better for vehicles
but, after much use, heightmap is the clear winner.
Force terrain implementation to heightmap if the physics region is
larger than legacy region size. This solves running out of memory for
very large regions.
Conflicts:
OpenSim/Region/CoreModules/Framework/EntityTransfer/EntityTransferModule.cs
OpenSim/Region/Framework/Scenes/SceneBase.cs
OpenSim/Services/Interfaces/IGridService.cs
OpenSim/Services/LLLoginService/LLLoginResponse.cs
(conflicts were debug statements that are commented out in master branch)
(like sitting on and activating a vehicle) and crossing borders.
This keeps better bookkeeping on compound shapes so BulletSim can
identify them when being freed.
the vehicle buoyancy if the vehicle is above its hover height.
This is a known misfeature of this vehicle flag which has been accepted
since it would break too many implementations. The problem is noticed
when creating a jetski-like vehicle that jumps over sand bars. A boat
normally is configured with neutral buoyancy and hovering at water
height. When it jumps the sandbar, it needs to have gravity applied
to get back to water level.
