[Opensim-dev] Question: would it be possible to add Havok to opensimulator..??

[AJLDuarte]

Hi,
	Cinder almost answered all.
	Viewers only use the mesh tools included on the Havok library
	For Opensim use, viewers use HACD a open source library, also used by Bullet for example.
	One may be better than other.. but that depends on versions.. meshes details  etc..
	It makes sense LL uses havoc, because they are already paying it
	And even server side they are not using the latest version, just because they don't need it.

	For Opensim servers, there is no sense in using a paid library product for physics.
	Even PhysX did had (still has ?) license issues.
	Many of the advances done on Havok, PhysX, bullet, etc, have not that great impact our needs for physics engines
	Those are great for a traditional game running on the client machine either a pc or a game console
	A example maybe the use of GPU on collisions processing (if they do manage to make it outperform main cpu). Only a few Opensim users could pay the extra cost of a server with a good enough gpu installed. Those running Opensim on home pcs with a good GPU, they need it for the viewer. Fluid dynamics, soft bodies, etc.. all great for a potential new viewer using then or a engine on top of them like Unity, etc..

	On Opensim server side the limitation is not on the physics engine used,  but on our own code using it
	The difference btw old ODE and ubODE is a clear example of that, both using the same library.
	Bullet physics engine is another, Bullet physics engine does perform a lot better on other applications.
	PhysX MOSES effort could not be used by Opensim, because it was still far from usable (and had license issues at that time)
	Even if fixed, it would not be  better than our Bullet, because is was done to just clone it, including its wrong implementation of some features (itself based on old ODE model), meanwhile improved.
	If fact seems even MOSES gave up on it, changing to the much better implementation of PhysX done by Inworldz on halcyon.
 
	So imo, what is the physics library used on Opensim is still not that relevant, and if any of those is properly implemented, most bottlenecks will be at our C# code side.

Regards,
	Ubit

(you all know my English is not the best, so take that in consideration reading...)

	



-----Original Message-----
From: opensim-dev-bounces at opensimulator.org [mailto:opensim-dev-bounces at opensimulator.org] On Behalf Of Cinder Roxley
Sent: Tuesday, December 19, 2017 19:33
To: opensim-dev at opensimulator.org
Subject: Re: [Opensim-dev] Question: would it be possible to add Havok to opensimulator..??

On December 19, 2017 at 9:19:57 AM, Haravikk (opensim at haravikk.me) wrote:


> On 19 Dec 2017, at 14:31, André Verwijs <dutch.glory at yahoo.com> wrote:
>
>
> i don't think Firestorm viewer devs are paying that.
> or made a deal with SL ..

Firestorm doesn't have to, because they're not the ones running havok; physics for SL and OpenSim are both handled by the simulator, so they're server side only. All the viewer has to do is show you what happens.

Mostly true. Firestorm doesn’t use the physics engine itself, but it does include the Havok convex decomposition module. This is the entire reason there are two different versions of Firestorm. Havok only licenses their product *per game*. So more than likely, each and every grid who wanted to use Havok would need to purchase a $65,000+ license to use it.

I don't think havok is an option unless they ever start offering a free license for non-profit uses; but as far as I'm aware it doesn't support OpenCL anyway, so Bullet is actually a better option anyway if you can throw some OpenCL capable hardware at it.

Havok does support OpenCL as well as DirectX Compute and is lightyears ahead of Bullet, but it isn’t free. I’m surprised how quickly everyone forgot that MOSES opensourced their PhysX implementation. It needed some work, sure, but it’s basically been abandoned.
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