Messages

76

Darwinbots3 / 2D or 3D?

« on: September 28, 2008, 05:54:46 AM »

I know you have probably been around this cycle of thinking before but bear with me.
Can we not simulate the cells as a circle?
They don’t have to actually look like a circle they could be a roughly circular polygon to allow for direct joining etc.
It would put alot less stress on the physics side of things. As it's the narrow phase collision detection that really screws you.

In fact the physics simulation could look a lot like the current DB2 simulation, circles joined to each other with a tie of varying stiffness; you could then display that as a lattice of polygons all neatly sealed up. The physics underneath just needs to approximate how you wish the objects to behave.

Which do you want this to be closer too, a scientifically accurate simulation, or a game?
If you want accuracy you either need to limit yourself to about a dozen objects or buy some time slots on a super computer

77

Darwinbots3 / 2D or 3D?

« on: September 28, 2008, 05:40:46 AM »

or something like this
http://www.youtube.com/watch?v=gHPDJS74F70...feature=related
in a simulated fluid like this
http://www.youtube.com/watch?v=9oGnCeE5wFM...feature=related

*puts reality goggles back on*

I would say we already have an upper limit of say 800 cells, if each one is described by 3 ridged bodies then we are talking a max of 2400 for the cells and say 200 for particles and projectiles, and that is probably our limit. 2600 objects constantly subjected to various forces and around say 15% of them involved in narrow phase collision detection at any one time is probably nearing the full load of 1 Core

78

Darwinbots3 / 2D or 3D?

« on: September 28, 2008, 04:52:48 AM »

http://www.youtube.com/watch?v=SvqY_pgA6DU...feature=related
http://www.youtube.com/watch?v=DFnmnMK1Yvw...feature=related
Heh Jello Physics would be cool, it's a soft body simulator, but it only looks to be capable of a few dozen active objects.

79

Darwinbots3 / 2D or 3D?

« on: September 27, 2008, 08:14:48 PM »

Well I don’t know if you’re the same but for personal projects I have an annoying tendency to get hung-up about a particular feature and want to keep re-working it until its perfect, which of course just means that the project doesn’t get completed in anything like a reasonable timescale. At work I just get told to leave it be and move on. Get the project up and running so the testers can start playing with it, then come back to look at bits I am not happy with and are in need of some adjustments or refactoring.
Half the time when you come back to it you end up agreeing it’s probably fine as it is anyway.

80

Darwinbots3 / 2D or 3D?

« on: September 27, 2008, 07:00:40 PM »

Well ok let’s try listing all the 2D managed physics libraries we can find then go though each one and review it.
Starting with...
http://www.codeplex.com/Wiki/View.aspx?Pro...=FarseerPhysics
http://physics2d.googlepages.com/
My quad tree used the geometry from Physics2D.net (again with its roots in Box2D)

Ideally it would be good to have the physics as a completely separate module that could be swapped out for another one on a whim. That way you could play-test them all

Also in regards to stacking, I don't think I have ever seen a physics engine do it perfectly. it's normally a matter of playing about with the parameters until you get something you can live with.

81

Darwinbots3 / 2D or 3D?

« on: September 27, 2008, 06:10:24 PM »

I thought chipmunk was the undisputed current flavour of the day in regards to 2D physics libraries I think I have seen an XNA port floating about somewhere too. From the demos I have seen it should be able to handle 2000 objects with ease, say a 1000 for cells and a 800 for clutter/structure in the environment and 200 for projectiles. I have only played about with 3D physics libraries and my own very basic 2D physics before though.

82

Darwinbots3 / P2P Internet Mode

« on: September 27, 2008, 05:42:36 PM »

I have been wanting to do something for the Xbox for a while (I have one too) It would be great for running and displaying the simulation and even sharing bots about.
does the new v3 have any existing graphical concepts? I.e. to look like you’re looking under a microscope

http://www.youtube.com/watch?v=w8O4OolGcPg...feature=related

Is the DNA going to be executed in a single thread (each bots in turn) or in parallel via a thread pool?

83

Darwinbots3 / 2D or 3D?

« on: September 27, 2008, 05:19:12 PM »

Hi, getting interested in this now, I have spend a good few hours now reading though the wiki and the forum for DB3 and I assumed it was going to be 2D but in the wiki it talks about a 3D simulation and plants with roots etc?

What is the current expectation for the physics simulation? And how advanced will it be?
The last time I played about with physics in a game each object in the world was approximated with a small collection of a primitive AABB  ridged body’s with an Octree for spatial partitioning as used in the broad phase collision detection. Then you can go crazy with what it actually looks like later on when rendering in the client (it was a networked game).  Though it would be cool to have a cell approximated as an OBB Polyhedron then it could really change shape and to join two cells you would pick the nearest face on each cell and join up the 6 vertexes.

As for digging, I have seen the fully destructible world demos but I wouldn’t know how to implement an ant digging a tunnel without creating the ground/wall from lots of smaller ‘blocks’ that can be excavated/destroyed.

2D would be simpler, by not a lot in any one area just overall, mainly it’s a little bit simpler and quicker for graphics (lots of objects onscreen), Collision detection, Quad tree instead of Octree.
Having said that 3D would be cool, but you have just given yourself a load of UI issues as I found out with my space RTS, you’re forced into coming up with some really innovative control schemes just to keep the UI usable if its not FPS based.

84

Darwinbots3 / P2P Internet Mode

« on: September 27, 2008, 05:08:31 PM »

Ok I would love to help, It looks like a really interesting project, It’s been like 7 years since I used any VB6 but my C# is current, I am experienced with sockets and GDI+ and a little bit of XNA, but I am sure TAO can't be that hard to learn.

85

Darwinbots3 / P2P Internet Mode

« on: September 27, 2008, 12:58:07 PM »

And in fact after more reading (so far I have spent most of the day reading this forum) with ideas like complex dynamic cell shapes and joins that could well take a cell update into the realms of 128 bits or more which considering the number of cells and frequency of change would make viewing over the internet far too slow, it would still be fine locally, but then what’s the point!

86

Darwinbots3 / P2P Internet Mode

« on: September 27, 2008, 11:28:31 AM »

Ah ok I have misunderstood, after skimming though aload of posts about P2P networking I assumed the talk was of a system closer to the like of Terrarium.

87

Darwinbots3 / P2P Internet Mode

« on: September 27, 2008, 10:31:48 AM »

Hi everyone, I just came across darwinbots.
I was originally just looking to see what was already about in the area of robot programming games (ala C-robots) with a view to creating my own in C#.
But having found Darwinbots have decided not to bother.

Anyway...

I have been reading allot about version 3 design decisions, in regards to networking what is the objective? Is this just for sharing bots in otherwise isolated simulations or are we talking multi-user simulation?

A multi-user simulation might be possible over a classic client-server sockets architecture, which would be the simplest way for networking this kind of game (relatively speaking).
The simulation would be run in a service to which one or more clients could connect and view the current simulation state.

It would better support:-

1)   Evolution Sims, You would be able to run your sim for months in the background as service and just load-up a client viewer every so-often to see what was going on. The service implementation could just save the sim when the service stopped and load it again when the service started.

2)   Different client views on the same data, you could have a basic win forms statistics overview client, a primitive 2D client and a swanky 3D client. These could be developed interpedently from the server and even independently from the server’s platform

3)   Independent simulation speed, it would enforce the total separation of rendering frame rate to simulation frame rate. The client can render as fast as it can, the simulation can simulate as fast as it can and the network can send and receive data as fast as it can, all Independently of each other.

4)   League and shared games, all participants could connect and view the simulation in real-time to check on the progress their entry was making. Users could just set up their own server (simulated environment) and other users can join and introduce their bots and see them interact with other user’s bots.

5)   Performance, it’s going to be the fastest and simplest way of any kind of multi-user simulation. Since this isn’t Counter strike there is no twitch user input or correlating feedback, you only really need to worry about raw bandwidth for sending updates. And in that regard you can just cap and rotate the number of bot updates you send in one tick, you would only need to send a reference ID and accumulated velocity delta’s as regular updates say about 32 bits per bot update, you should be able to manage an update rate of about 32 per tick (in a single UDP packet) with a tick rate of 5 per second, which would give you about 6.7kb/s (160 updates per second) per connection. Obviously for local connections you can achieve a display which approximates the status of the simulation much more tightly by using tick rates closer to that of the simulation frame rates or by updating a larger proportion of the bots in each tick.