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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1
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3answers
962 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 ...
9
votes
1answer
2k 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
187 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 ...
19
votes
7answers
31k views

In Pong, how do you calculate the ball's direction when it bounces off the paddle?

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
2answers
1k views

How to create simple physics for a group of balloons colliding in the screen (2D)

The game is 2D, how can I make simple physics for a group of balloons colliding in the screen. What I need is the balloons not to overlap and to bounce when they reach the limits of the screen or ...
3
votes
2answers
302 views

Good ways to edit arbitrary collision shapes for 2D physics engine?

Assume you have several 1024x1024 textures which contain an arbitrarily shaped and relatively complex cave system whose walls need to have collision polygons defined. The polygons need to be convex to ...
14
votes
3answers
4k views

How do I handle moving platforms in a platform game?

I don't want to use box2d or anything, I just want simple moving platforms (up-down, left-right, diagonal and circular paths). My question is to handle the update order / control hierarchy so that the ...
4
votes
2answers
1k views

A good place to learn about Game Programming with Mathematical Vectors?

I am looking for a place in the web where I can turn my current game development process into a vector based approach. I am sorry If this question has been asked once. According to my google search ...
6
votes
4answers
8k views

2D AABB collision response

I'm making a simple platformer, and I wanted simple collision handling. So I gave all my objects an AABB hitbox and tried to resolve collisions. However, I can't get it to work. My main character has ...
8
votes
1answer
452 views

How can I copy or back-calculate definitions for an entire b2World?

I'm working on a platformer where I'd like to be able to move or copy bodies between multiple Box2D b2Worlds. The desire has cropped up three times now - moving objects between documents in my editor, ...
8
votes
2answers
3k views

Box 2D Set Origin

I'm trying to set the origin of a box2d shape. By default, a shape rotates around the center. But I'm trying to get it to rotate around the left of the shape. Like a clock for example. I've heard of ...
6
votes
3answers
3k views

Implementing a 2D Platformer Game Engine

Any ideas where I can find info about making 2D jump & run games? I need some general ideas, so I wouldn't reinvent wheel (at least where game design is concerned). Another point is that I am ...
4
votes
1answer
370 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
995 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 ...
32
votes
6answers
11k 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
652 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
832 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 , ...
9
votes
4answers
694 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? [closed]

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 ...
72
votes
5answers
35k 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 ...
1
vote
5answers
10k views

which is the best physics engine for flash as3? [closed]

i am a game programmer and i use actionscript to do all my collision checking, boundary checking etc...but recently i noticed there are things called "physics engines" that help me concentrate more on ...
9
votes
3answers
329 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
457 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
14
votes
4answers
3k 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 ...
2
votes
4answers
985 views

Good way to implement really basic physics in Flash?

I'm making a somewhat simple side-scroller in Flash. The way I'm currently doing the really basic physics(you don't fall through floors/can't walk through walls) is that I have a big symbol of all the ...
-1
votes
4answers
1k views

Open Dynamics Engine

Has anybody used this library before? What were your experiences? Pros/Cons?
11
votes
4answers
5k 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 ...
8
votes
6answers
663 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 ...
212
votes
10answers
66k views

When should I use a fixed or variable time step?

Should a game loop be based on fixed or variable time steps? Is one always superior, or does the right choice vary by game? Variable time step Physics updates are passed a "time elapsed since last ...
10
votes
2answers
8k views

Using The Box2D Polygon “Set()” function?

I'm using the Box2D physics engine. And there's a type of shape for box2D called b2PolygonShape. In this class, you can create polygons. There is also a Set() function that takes an array of points ...
8
votes
3answers
6k views

Box2D Check If Point Intersects a Body

Is there a way to check if a point is intersecting a body? For example, lets say there's a body in the world at a position of (100,100). Is there a way to check if a point at (100,100) intersects ...
11
votes
3answers
6k views

Box2D Get Bounding Box of a Body

In Box2D, I was curious if it's possible to get a bounding box of a body already created in the world. So basically, the Body is created, it's interacting with the world and such. And I needed that ...
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 ...
10
votes
3answers
1k views

How do I calculate the forces exerted by a taut wire wrapping 2D objects?

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 ...
31
votes
6answers
6k 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. ...
9
votes
1answer
576 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 ...