Posts Tagged ‘physics talk’

h1

physics talk abstract and slides

December 25, 2008

So now that my talk is done and over with, I guess I promised earlier to post my abstract/slides. SO IM POSTING THEM JESUS DONT KILL ME OKAY KAYTHX.

They’re here, and you must use the video signal analysis in your brain to interpret the pictures. No one ever gets that and they’re all like ROFLMAO I CANT SEE WTF. silly silly people.

download: physics_talk_08_ccis.7z

That takes care of that.

h1

cs lab ho!

December 18, 2008

I’m currently up in the CS lab. I got my physics test running on their machines. I have the Ubuntu portion of my laptop working with their smart boards. I am now in complete control of this galaxy! Or not.

But man, I’m psyched! This is it, man! 13:00 I’m giving my talk. Then I’m watching several others, including the Othello game presentations.

The CS students are in here freaking out because everything in Othello suddenly broke down, and fixing all kinds of weird crashes related to timing and the AI scripts. T_T But it’s quite amusing. It doesn’t suck as bad as it could, but I’m sitting here all smug because all my stuff works just fine. hehe… 😀

h1

aspergers + adhd = omg problems

December 17, 2008

That’s the second half of the puzzle!  I am definitely an Asperger’s according to my shrink.  I wasn’t told earlier because it might ‘disturb’ me.  This gives me the feeling that nobody knows anything about me, primarily because I have ALWAYS felt better knowing everything about everything.  Here I am wondering why I’m such a freak, then suddenly: “oh, well, you know, you’re like Asperger’s and stuff but we decided not to tell you a long time ago because it might make you feel bad.”  Ooooooh, well thanks for telling me in such direct and punctual fashion, jerks.

Right.  Last time I checked, ignorance is terror not bliss.  How do you think the Iraq and 9/11 coup worked so well?

Well, shucks, it looks like those ‘terrorists’ have attacked us.  No, don’t suspect us or anything.  No, those completely incriminating pictures can be explained away by *not* fabricated science.   Look at this will you?  It totally vaporized!  That explains why the ‘passports’ and ‘DNA evidence’ survived.  Hey, shut up.  Obviously we have to attack those, um, al-Qaeda fiends responsible.  Also, everything ever is linked to al-Qaeda, so let’s just bomb them all!  No, it has nothing to do with oil or world domination, don’t be ridiculous.  Pffft.

I’m thinking of putting a personality badge up everywhere, it’s somehow a comfortable way of communicating my strangeness.  The one produced by the tests at mypersonality.info.  I got “Logical, Musical, INTP, Engineer, Intellectual”.

So, as for the HDR demo, HDR won’t be officially implemented until the scene manager exists.  This was done using the raw utility available on my renderer class, and some shaders.

What’s next?  Probably D3D9 support, and a more flexible vertex buffer.  That is to say: I will allow them to select static or streamed mode (for now it is always static.)  I must quit for tonight, I’m dead tired.  I need to catch up on sleep, as my talk is at long last finally here!  THURSDAY WE WILL ROCK THE HOUSE WITH GEEKERY BITCH.  Other talks include the ongoing Othello networked game program, the Python scriptable AI of the Othello program, the new ZFS filesystem compared and contrasted with the EXT filesystem, and lastly, something about internet security design and issues.  Should all be cool and baller and awesome.

Until next time, I will tear the flesh from your bones bc I zombie4life bitches!!!11!!

h1

hard to blog in nirvana

November 14, 2008

So much good stuff has been happening to me at once.  I feel awesome!  I haven’t updated in a while for a coupla reasons that have been way too cool for me to care.

It looks like I’m actually going to CCIS this spring!  This is such a weight of uncertainly lifted off my mind.  For this reason, I will obtain a laptop.  Yes, a laptop.  My first new computer in ten years.  I’m all giddy!  I am such a performance and optimization wank; I wonder how crazy fast my code is going to run on there.  I’ll also have the power to implement one of my favorites, something I’ve never had the GPU to do before: GPU programs!  Fragment programs, vertex programs, even geometry programs!  This is really sweet.  Shader time.  My excuse for getting it was not empty, but in fact true: I will need a laptop in computer science.  This is very high end though, and will serve me for years to come.  Unless it breaks or gets stolen.  Let’s not even imagine that.  T_T

The other reason is that the whole CCIS talk thing is going forward!  I got a date set too.  Can’t remember it exactly now, this is why I have a schedule.  😛  It’s just before winter break, on Thursday.  December something.  This is when attendance will be highest for the talks in general, so I’ll get a very large crowd, all of them computer scientists or geeks in some way… wow.

When I got the first email on it, I seriously thought I was being fucking punk’d.  This is the first really good thing that’s happened to me in my whole life, aside from my meager group of friends who probably have no idea they are the reason I am not dead in the bathtub.  I thought I was luckier than usual when my mom let me go back to seeing my shrink after I left highschool in order to regroup.  My sanity hung by a thread then.  But now the funeral dirge is over, failed childhood fuck off, it’s time for a sweet-ass talk on physics!

Boy am I pumped.  I sure hope this goes well.  I feel it man, I feel the momentum building.  This could be the beginning of a much less hopeless and miserable chapter of my life!

Here also is Circus Maximus, the prog band I just discovered.  They are the definition of full-on prog wankery mixed with subtle and powerful meaning in real music.  They blend function with form almost as perfectly as Opeth themselves I daresay!

h1

looks like talk is a go + preparation of examples

October 25, 2008

So, it looks like the talk is gonna be a GO.  :3  We’re reserving a room for some coming Tuesday.  I’m basically preparing like a crazy person, because I need to make this count.  Think about it… this could literally evolve in to a free ride for me.

I’ve got my slides, peer reviewed them with a friend, (who was surprisingly supportive,) and got my presentation planned.  Now I’m working on the software aspects of my presentation.  I want the examples program to be at least half full of numbered demos.  I’ve got a Pinchinco like example with balls falling through triangular pegs, but I also want some more practical demonstrations.  Varying restitution, varying friction, dominos, maybe a character control application demo.  I fixed the timing code in both the testbed and the examples program, so that’s all good.

It’s a race to the finish line, and this time it’s not on a motherfucking circle track!  There’s actual progress to be made!  Why couldn’t highschool ever be like that?

h1

time of impact islands + talk presentation thingy

October 23, 2008

HEY HEY HEY HEY HEY HEY HEY HEY *gets smacked down*

GUESS THE FUCK WHAT?

You’re not guessing.  I’ll tell you!  I’m actually giving a talk at Columbia College about my physics project.  Here’s essentially what I got off Dr. Liow.  Dr. Liow is probably one of the best people to recognize anything you do, because he seems like he’d be honest if he didn’t like what you’ve done.  In an email he was all: “Your program is interesting.  Do you want to give a talk about it during lunch, blabitty bloo, blabitty bloo, blabitty bloo, it’s totally unofficial, blabitty bloo, it’s in a room with some people, blabitty bloo, blabitty bloo, this is totally gonna be like a presentation during lunch so omg r u interested?”  Man, I hope he doesn’t read that.  Meh, I don’t really care.  Anyway, I was all “shit yeah” and he’s all “omg I haven’t even checked my email yet so I haven’t responded yet.”  So I’m still waiting for a reply.  But I’m psyched, and I really like the idea of publicising my physics engine, if even on a local scale, so I’m definitely going to be there.  I’m gonna make slides, demos, tacos, nachos, and paper mache!  Okay, actually just slides and demos.  Can you tell I’m giddy?  Huh?  Is it showing?  ANSWER ME!  YAAAAAAAYYYYY!!!!!!!!

This is pretty awesome.  All I’m sayin’.

NOW.  On the topic of actual work that I’m doing on physics.  You may have thought about time of impact and how it would slow everything down.  You’re damn right it will.  The question is, how can we optimize it as much as possible?  In the most accurate TOI model, you find the pending collision with the smallest TOI, advance by that amount, (of course setting a minimum fraction of total timestep so we don’t get stuck at toi==0.0 forever,) handle collisions normally, run the impulse solver, and repeat until the timestep is done.  But what about Joe McStranded off in the distance who won’t collide with anyone for at least a dozen frames?  Should we waste time sub stepping him?  NO.

The solution: islands.  This is a technique I am shamelessly stealing from Bullet Physics.  But we all stand on the shoulders of giants, right?  Anyway, an island is essentially a field of objects which will all interact with one another in the next frame.  An island of objects are all linked by constraints, contacts, and bounding box sweeps.  Anything which may collide with other bodies in the island or be affected by a body in the island is in, basically. This means the loners are all omitted from the expensive sub steps in time of impact solving, and this also means smaller islands who will do less sub steps than the bigger ones.

So, as for sweep algorithms, I have circles down, and I’m trying to do the MSA-sweep now.  I’m not exactly sure of how it will turn out on rotating bodies, as I’ve said before.  I may wind up using the conservative advancement method.  I’ve said this before, I’m just rehashing it.

Think about using islands in your own work.