SL Physics Comparison

I did a test of knocking down 1000 physics enabled boxes in the new Blue Mars building tools, and recorded a video:

http://www.youtube.com/watch?v=8dUBNZ-Qtog
http://www.youtube.com/watch?v=8dUBNZ-Qtog

For those with experience in Second Life Havok physics, how many items can you drop in SL and have comparable performance. I'm curious how they compare. In my test I was getting about 24fps. I know that running physics on my PC is not directly comparable to running it on an SL simulator host (my PC is faster, for one thing *smile* i7-920 vs dual core Opteron 2000s or whatever)

And yes, those are half meter plywood cubes *grin*

Does BM really do physics on the client side? Even though the video fps seemed fine, the physics processing looked a bit slo-mo to me. Is there something like the SL stats bar in BM to show you how many physics fps are happening?

There's a number of physics videos for SL on youtube - just search 'havok4 secondlife' and you'll find some. I like the panchinko one. Dunno how many objects they have going at once, though.

Thanks, I looked at the Pachinko video, and it looks like 100 items in motion caused severe lag (TD= 0.50).

Yes, it really does physics on the client side, since I ran that test on my practice "city", and was not logged in at all to their servers. The development model is all your content creation is done offline, and assembled with a "City Editor". The City Editor can switch from editing mode, where you can place objects, change their textures, etc, to preview mode, where it loads a default avatar that can interact with what you build. That is how I did the video, in preview mode.

Once you are done building, you upload the entire city and its contents to their servers, and then visitors will download it in order to visit. That takes care of the 'static content'. Avatars and inventory items like furniture still have to be streamed in real time. Eventually they will have a way to do incremental updates to a city. For now we download it as a unit. (Actually, they did a patch to their welcome area for Halloween, but we had to download it manually and install it, what they need is a way to automatically do that - Blue Mars is still in early beta, so a lot of stuff isn't finished yet).

If there is more detailed stats available I have not found them yet. I re-ran the video without touching the boxes, and got around 27fps, vs 22fps with them in motion. So 1000 objects in motion makes a noticeable difference. The way their physics is set up, these type of objects are static until something makes them move, so hitting one of them with my avatar starts a chain reaction through the stack. Scripted objects can have physics running all the time on them. There are also static objects which never have physics for themselves, but have collisions with avatars, and objects which don't have collisions

Using the BM build editor is a poor comparison since there's no network. Do it over the network and then post the results.

That video looked pretty good, albeit somewhat slow motion.

Impressive Clip

Little Off topic... recently some direct links appear in the posts. It is now possible to use a working tag URL in the BBCode??
Edit: I saw thank, youtube works with IMG....

all links can work with IMG tags, but if it doesn't show properly when you hit preview, simply add a ? to the end of the url. (adding one to a link that already contains one will break the link in most cases, and apparently the software doesn't like sub-sub domains of the format x.y.z.com/whatever so be aware of that)

Many Thanks for your details

For those who might want to try it out, and to dispell the myth that you have to be a professional content creator to build for Blue Mars:

The purpose of this pack is to be a "starter set" to help new Blue Mars developers. Learning both the Blue Mars editing tools and 3D and graphics software all at the same time is a lot to start with, and not everyone has the textures or the software to convert them to the right format. Even if you have those other programs, a set of basic shapes and textures can be handy.

So this package contains about 135 pre-made basic shapes and 300 textures that you can use directly in the Blue Mars editors, and step by step instructions. For more advanced or custom items, you will need to learn those other programs, but you can do a lot with just this set. For those coming from Second Life, this is essentially a prim and textures kit, and reduces the basic building to the same level as making stuff in SL with prims.

Blue Mars does not have a 10m size limit for objects, but it does have a problem with collision proxies when you change only one dimension of an object. That's why the kit as a variety of shapes of each basic type. You can scale them to any size as long as you change all three dimensions together.

If any part of the instructions are unclear, or if you have other items you would like to see, please let me know so I can improve them. I would also love any feedback on how you think it compares to SL building in difficulty, ease of use, etc.

Download at:

http://www.mediafire.com/?znygmyz2yqh


Photo at:

http://lh4.ggpht.com/_A5TdX8sjcr8/S0ZzfQYAqKI/AAAAAAAAAVs/IQn8S6y1ziM/s1440/Builders%20Kit%20v0.5.JPG