Relating to the motion of objects through space and time. Including concepts such as acceleration (thrust and gravity), mass, collision response, friction and more.

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8
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4answers
1k views

Not sure how to handle “deceleration”

I say "deceleration" because I'm not using acceleration at the moment (it is being calculated, it's just set to 0 0); what I mean is moving the velocity back towards zero, eventually stopping. I'm ...
5
votes
3answers
2k views

Car (or other “object”) acceleration and braking: how to?

I'm not good in math so I'm here to ask you how to manage, in a simple 2d game, the car acceleration and braking. I'm trying to develop it (as a hobby) in c# and sdl.net.
8
votes
1answer
1k views

Realistic slow-falling snow algorithm?

Is there a good algorithm that simulates falling snow? I'm particularly interested in snow that falls slowly, so it doesn't quite fall in a straight line but deviates a bit. Maybe even including ...
4
votes
1answer
414 views

Taking Physics into account for AI Planning

What I've seen in most Game Engines and game engine design is that the Physics Engine is the be all end all system. Basically, AI for example may want to travel to some position, but it simply ...
1
vote
3answers
879 views

What's the best open source physics engine to use with JOGL? [closed]

I have a past with jbullet but the existing jogl compatible sources and demos seems uncompleted. I have managed to implement it to an extent but still looking for a better documented engine with more ...
8
votes
1answer
1k views

What are the common character animation techniques used in tile based hack&slash games?

I wonder what kind of animation techniques are used for creature and character animation in modern hack&slash type tile based games? Keyframing for different actions may be one option. Skeletal ...
3
votes
4answers
184 views

What environment should I use if I just want to test different math things?

For example, I've asked about the breakout formula to calculate the ball bounce. Inside of XNA, I don't know where I would code this and to even display something I would need a lot of code. Is there ...
14
votes
7answers
17k views

How do you calculate where a ball should go when it bounces off the bar?

I'm trying to wrap my head around this very Hello World-y problem in game development. I've created a TicTacToe game in XNA so I guess the next step would be a breakout clone. Keep in mind that I ...
4
votes
1answer
350 views

How to take into consideration the effect of initial rotation of a ball hitting & reflecting off a surface

Hey all, I am trying to take into consideration the effect of inertia of the initial rotation of a ball, hitting a surface, into the exit velocity vector of the ball. My current theory is this: ...
19
votes
6answers
1k views

Data structures for interpolation and threading?

I've been dealing with some frame-rate jittering issues with my game lately, and it seems that the best solution would be the one suggested by Glenn Fiedler (Gaffer on Games) in the classic Fix Your ...
2
votes
1answer
953 views

cocos2d: syncing CCAnimation frames with Box2d Shape manipulations

my cocos2d game currently has a ccsprite attached to a box2d body. during the game i apply different CCAnimations on my sprite, i would like to perform certain manipulations to the box2d body ...
4
votes
1answer
2k views

New Vector Calculation for Elastic Collision of Circle and Fixed Rectangle

I am writing a fairly simple breakout-style game for Android phones. I have successfully detected the collisions between the ball(s) and bricks. The problem that I am having is in calculating the new ...
27
votes
6answers
7k views

About floating point precision and why do we still use it

Floating point has always been troublesome for precision on large worlds. This article explains behind-the-scenes and offers the obvious alternative - fixed point numbers. Some facts are really ...
15
votes
3answers
588 views

Solids as high viscocity Liquids

A friend of mine and I were discussing different idea for allow materials in a world to be destroyed in a very piecemeal fashion and he proposed the idea of representing solids as very viscious ...
4
votes
1answer
792 views

Problem with box2d at beggining

I have problem with simple box2d physics: I have two bodies : 1 - static box , 2 - dynamic box. I only want to this dynamic box fall on this static, and lay. But now it looks like that at end , ...
7
votes
4answers
612 views

How do I make a vehicle move to a point and stop without overshooting or oscillating?

Ok so consider we have a vehicle like the one I described in my answer to this question, with a 2D position, velocity, angular velocity, and drag/friction. It can accelerate and break by a variable ...
3
votes
3answers
1k views

Optimizing Bullet and ODE Physics on consoles and mobile phones

I'd like to use either Bullet or ODE on low powered devices (mobile and consoles), but the frame rates are below the acceptable 25-30fps for simulations. I've found that one articulated body by ...
11
votes
3answers
2k views

Pretty open source game/rendering engine?

It might be outside the domain of open source (as there isn't much in the way of open source games that would want/need to implement all these) but is there an existing open source game or rendering ...
62
votes
5answers
25k views

Good 2D Platformer Physics [closed]

I have a basic character controller set up for a 2D platformer with Box2D, and I'm starting to tweak it to try to make it feel good. Physics engines have a lot of knobs to tweak, and it's not clear to ...
8
votes
3answers
316 views

Connecting physics simulations with different coordinate-systems

I want objects to move between two physics simulations through a "window" and collide with those from both simulations in case they intersect the window plane. The coordinate systems of the ...
-5
votes
2answers
420 views

two balls stick together in a pool game? [closed]

when multiple collisions occur between balls..sometimes they stick together..mostly in cases of either of the balls having high velocity..can somebody explain pls
12
votes
4answers
2k views

How do I calculate rotation caused by bounce friction?

Following on from my previous question: I have the ball quite realistically bouncing from surfaces it hits. Now I'd like to make it spin from the friction of the hit. Showing this is simple enough: I ...
6
votes
2answers
2k views

How to calculate the exit speed of ball bouncing off a solid surface

Hey all, I am working on a simple game to include some rigid body dynamics, involving placing (moving & rotating) some springs to bounce a falling ball into a target area. My problem is correctly ...
-1
votes
4answers
926 views

Open Dynamics Engine

Has anybody used this library before? What were your experiences? Pros/Cons?
11
votes
4answers
4k views

Vehicle physics with skid

How would I go about creating vehicle physics for a car that can loose traction? I want it to seem like the driver has a flat foot, so when you press the gas, they cars driving (rear) wheels loose ...
7
votes
6answers
623 views

Physics library internals

I've seen box2d and bullet ports into javascript, but neither of them attracted me particularly, except by source code. It all seemed, after all, quite simple once I looked inside them. But what are ...
172
votes
9answers
43k views

Fixed time step vs Variable time step

What is better for games when developing game loops, fixed time steps or variable time steps? What type of games are better with one or the other? Variable time steps: With variable time step, I ...
2
votes
3answers
1k views

XNA: Deforming/Destroying a model

I want to be able to destroy and deform a car in-game. For example, I want two cars to crash and a) break the meshes apart (probably applying force to fly them apart) and b) deform the mesh (like ...
8
votes
3answers
992 views

Forces on a wire in a 2D environment? (Physics)

Assume I have a physics primitive I am going to call a "wire" wrapped around a 2D environment (as described in this question). Here's an illustration of what that might look like: In the example ...
26
votes
6answers
4k views

Implementing a wrapping wire (like the Worms Ninja Rope) in a 2D physics engine

I've been trying out some rope-physics recently, and I've found that the "standard" solution - making a rope from a series of objects strung together with springs or joints - is unsatisfying. ...
6
votes
1answer
272 views

Changing orientation by applying torques

Suppose you've got an object floating freely in space. You have a vector you want this object to point towards, and a vector representing the direction it's currently facing. From these two, you can ...