# GRAAAAVITY!!!

Hi guys, I just started to really get my head around the GE Python scripting tonight. Great to speak to you all on FreeNode.net! I must say thanks for all the help, encoragement and laughs.

So IPKnightly pointed me to some great resorces. Thanks dude. Here’s what I came up with regarding the simulation of gravity. I know it’s not fully Newtonion yet; but it’s only been a couple of nights!

Download it and give it a whirl! You know… if you watch for long enough, something weird starts happening. I guess you could call it digital resonance. Like Knightly said… thank God-God dosn’t code like I do!

Peace blenderz!

Cool, you’re off to a great start.

Heh, ever fix that moonlander thing? Hmm… only thing missing from this .blend are the cubes exploding when it hit’s earth. Lol, as of right now, my laptop freezes up from the physics calculations. For earth try sphere UV calculation. It looks a lot better, has no seams, except for it’s kinda weird on the top and bottom tips.

Jason Lin

Well this is the start of me fixing the moon-lander thing. Cause I wantto make it so you can really fly the whole way around the moon. Hense learning gravity physics.

I’m gonna get some nice bump maps from NASA and do a GLSH version. So you really can fly around the moon realistically and land on any which side you choose.

Cool eh?!

What do you mean about spherical UV mapping? How do I do that?

For some reason I can’t download the file… it just comes up with the source code and when I select ‘Save Target As…’ it just downloads the HTML file :-?

Oh and spherical UV mapping is simply mapping textures in a spherical manner - to do this you need to first select the faces (in ‘UV Face Select’ mode), press U and then select ‘Sphere’ from the menu. Note that the direction in which you face in the 3D view depends on the shape in which the net is mapped, make sure the rotation of the earth is set to 0 on all axis and switch to front view before you select the mapping method.

Hope that helps,
From Daniel

That;s great, i will try that.

When you click ‘Save Target As…’ in the box that comes up select All files under Save as then rename the file 'My1stGravSim.blend ’ making sure the .blend is a the end.

That’s awsome. Being interested in the manipulation of gravity within the game engine myself, I am finding this very interesting.

O, and maybe you know this already, but using the bullet engine causes the cubes to just pass through the earth and go straight to the center. If you know why this happens could you please tell me. I think it might be another bullet engine bug, so im just trying to make sure.

Also the lighting seems to cast shadows of lesser quality when you start game. Does anyone know why that happens?

Very simple and yet it works fairly well. On my computer its a little jerky sometimes and it slows down considerably when the little red balls try to jam themselves through the earth and the collision detection tries to keep them out. Keep up the good work.

Yeah I cant be slow on some machoines… but that’s just because there are tons of rigid body ojects making calculations. When I finish making it into Lander, there will only be one gravity objext, and it wont have rigid body.

Man! I keep saying “objext” in stead of objects! %|

I think there’s something funny going on with the floats variables of the ridig bodies though. There’s too many calculatoins for what we are seeing, so something weird is going on. ANy ideas anybody?

By the way, I like your avitar Social, pretty cool.

Use the bullet engine perhaps? (F5->World Buttons->From Sumo switch to Bullet). That is if you can figure out how to fix the cubes going through the center of the planet problem, because thats what happens when I tested it using Bullet. (it didn’t seem to detect the collision, maybe a bug but im not sure)

Thanks. I made it with Flash MX.