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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32
votes
6answers
5k views

Analysis of Mario game Physics [closed]

I know there's a breakdown of Sonic the Hedgehog physics found here, and I was wondering, does there exist a breakdown of any of the Mario games? Something similar to this but for Mario is what I'm ...
8
votes
6answers
649 views

Ragdoll on alive creatures: has somebody already implemented it?

I find that a dead creature falling realistically is boring. I wonder, has any game implemented an animation system where the model moves depending of the muscle forces and the velocity of the limbs, ...
3
votes
5answers
337 views

Forcing one projectile to follow close behind an initial projectile

I'm shooting out a projectile and I want another projectile to closely follow it. I can't simply shoot out the second projectile at a slightly lesser time because the first projectile may change ...
33
votes
2answers
4k views

Water/Ocean simulation and physics

I'm looking for some references about water simulation, and how to model it's interaction with bodies (like boats, ships, submarines). I've found a lot of references on the visual aspects of water ...
5
votes
3answers
2k views

Resources to learn programming rigid body simulation

Where I can start learning about simulating rigid bodys 2d and 3d ?
4
votes
1answer
2k views

Farseer and 2D Action sidescroller game

I'm thinking about using Farseer inside my game (I'm not good in physics), which isn't a bad idea. However something happened while I was thinking about that, I found this tutorial: ...
6
votes
2answers
273 views

Self-righting agents that have fallen over

I need insect-like agents that have fallen/rolled on their back/side to naturally re-orient themselves. The agents are modeled as simple cuboids in the physics engine (Bullet) to approximate an ...
7
votes
2answers
4k views

Is it worth it to use Bullet for 2D physics instead of Box2D for the sake of learning Bullet?

There isn't much more to the question. I'm not concerned about overhead, as I'm sure they are both fine for my purposes. Basically, I am familiar with Box2D concepts because of the Farseer Physics ...
11
votes
4answers
1k views

When should I use a physics engine?

Since I found out Box2D, I'm using it for kind of any game-like application I try to write, from very small prototypes or small programs to test something, to actual projects. Thanks to it it's so ...
4
votes
2answers
643 views

How are physical model programmed in simulation games?

Being a Gran Turismo fan, I'm wondering what are the algorithms used to compute realistic behavior for friction, aerodynamism, velocity, curves etc. Also, are there sophisticated ways to simulate ...
9
votes
2answers
1k views

How to implement 2d explosions that will cause damage taking into account covers and distance?

How can I implement a 2D explosion in a way that it will cause less damage to characters that hide behind crates or other cover? Ideally damage will depend on the strength of the cover (e.g. metal ...
4
votes
3answers
661 views

What do I need to change in Box2D to work in pixels?

Box2D seems to be set up in such a way that you cannot work in pixels (i.e. physics scale = 1). It produces very strange results as it hits maximum speed limits at low speeds and looks very strange. ...
5
votes
1answer
464 views

Strangeness when simulating a chain

I'm using box2d and I simply hook up 10 points each with a similar length constraint to the adjacent point. When I move 1 point, the others follow just like a rope/chain. Just like one would expect. ...
5
votes
4answers
356 views

How would one generate a texture for cracks in different materials?

I would want to have the ability to simulate different variables like brittleness, or other variables to get varied end results. I would mainly need to generate impact cracks, so it would need to ...
6
votes
2answers
2k views

How can I implement rectangle collision response?

I am working on a game in JavaScript and my current implementation of collision uses the shortest distance to push the intersecting object away, which isn't always correct. I've made this diagram of ...
3
votes
1answer
756 views

How to create complex Physics scenes with the Havok Content Tools

For example, Havok Content Tools allows you to define physic bodies, properties, connections, etc in Maya, 3d Studio Max, etc. For creating full scenes/levels is this really the correct approach or ...
3
votes
1answer
836 views

Fundamental physics component(s) in component-based game engine

What are the "smallest" physics components in your component-based game engine? Would it make sense to create something like Positionable, Rotatable, Movable, Collidable and combine them the way you ...
5
votes
2answers
674 views

3D Particle-Geometry collision

I am programming a particle engine for a 3D game written in XNA. I was wondering if somebody could point me in the right direction or perhaps give me some pointers in making the particles collide with ...
8
votes
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
883 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
185 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
18k 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
353 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
958 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
593 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
797 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
616 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
422 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
624 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 ...
174
votes
9answers
45k 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
1k 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
276 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 ...