Speaking of which, I found this error in your pseudocode.

// b = [b0 + b1.t] . [b2 + b3.t]

it should be:
b = [b0 + b1*t] /* add, instead of multiply */ + [b2 + b3*t]

I''ve tried the code, but still had no luck. However, I''ve recently read a little more on quadratics in collision detection so I will give it another try. If that doesn''t work, I''ll resort to Bouncer''s method of connecting particles to approximate shapes.

I've finally got the thing working to a level I'm happy with. Penetration happens only in extremely fast movement; otherwise, it is exactly as I wanted to accomplish when I started this whole thing about a year ago. All collision detection and response is incredibly simple yet provides a very believable simulation.

The "solution" to the dynamic line collisions is so damn simple; I cannot believe I was thinking about quadratics! All I had to do was expand the line into a capsule with a radius equal to the larger of the endpoints' velocities. I've rewritten the entire engine and now it is more flexible and refined.

If anyone would like to see what I have now, I'd be happy to upload the new demo. Otherwise, I'll add a GUI, textures, and make it really visually and aesthetically impressive with a simple game demo, rather than the crude graphics I have now. It'd make for a nice surprise :)

Well since I've let my friend try it, I mind as well let you guys:)



kycVerlet.zip (130 kb zipped)

very kind of you sir.

Yes, it's working very well. :)

There are a couple of of times a triangle edge intersected the large sphere. Haven't seen it happen with smaller spheres.

nice! ;)

I'm still working on this :) So far I've added textures, and particles are subject to mass. I've also made some fixes to collision detection and response so the system is more stable. XML support is added, so maps can now be edited. I'm trying to get particle-particle friction working better, but it's currently tolerable and does not subtract from the fun factor. I'd just like the system to be more flexible in case I'd ever want friction to be an important gameplay factor.

Now I just want to work out a few kinks and then I'll get to the widgets. I'm also thinking about making a detailed tutorial about how I'm detecting collisions and resolving them. I'd just like a show of hands to know if the tutorial would be helpful and is worth writing. Now that there are tutorials from olivier, jamie, and metanet, I don't know if people would still be interested in my take of 2d "physics." Just so you know, my methods are unconventional as I just go by what's easy and make almost random tweaks until I get the desired effects. I don't know if it's mathematically correct but it's simple, inexpensive, and looks good, so consider it an idiot's guide to fake physics =)

I'm almost done with a little game I'm entering in a competition.
It's 2D ragdoll fighting with some very simple yet surprisingly cool ai. The game has "bullet time," and features Spiderman with webslinging action :P and possibly 2 other characters to choose from. The ai opponents will be based on seemingly animalistic behavior, such as vulture or wolf. For the time being I plan to support 2 players on the same same computer and about 10 ai opponents. I promise to have it in a stable playable state in 2 weeks, but demos will be available asap as I don't have much further to go.

If I get the chance, I'll upload a screenshot later tonight.

spiderman, right on time!

Is that anything like that
Ragdoll kung fu demo?

That ragdoll kungfu looks interesting, and I'm rather tempted to try making my own version of it.

My game, however, is more like ragdoll megaman :) It's all about slamming yourself skillfully on your opponent and building up your character's strength. The adventure mode will be much like hic quest on the TI-Basic. You will money by fighting 10 different ai opponents, who can be fought over and over again until you get comfortable with the controls or to earn more money. With the money, you can increase your intelligence (increases head mass), or pump up your legs (increase leg mass) :) You can also purchase a skateboard (the smaller board player1 has in the demo) and a skateboy 9000 (the bigger board player2 has in the demo).
You start out without a skateboard, btw, I only put it in the demo to demonstrate the coolness of it:) You can edit out the constraint in players.xml to get an idea of how it'd play when you first start out. Play around with players.xml by changing masses or adding more particles/constraints. Be careful when you do that, because I have not been strict on checking for errors but you shouldn't have a problem if you're careful.
Be sure to backup files before trying to edit them.
There are probably more loose ends I haven't mentioned, but I'll keep shut for now since the release is near!
I'll try not to dissapoint :P

bump, cuz i see some people battling the same problems so maybe this'll help them.