Box2D is an open-source rigid-body 2D physics simulation library for games, written in C++.
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Good 2D Platformer Physics
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 ...
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votes
5answers
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2D Rope Collision Detection
I'm wanting to create a rope that can collide with objects like in the following youtube video:
2D Game Physics Rope
I'm thinking that you implement the verlet integration which uses points and ...
7
votes
1answer
378 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, ...
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4answers
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Best strategy (tried and tested) for using Box2D in a real-time multiplayer game?
I am currently tackling real-time multiplayer physics updates for a game engine I am writing. My question is how best to use Box2D for networked physics. If I run the simulation on the server, should ...
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3answers
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How do you do AI path following within a 2d physics engine like farseer/box2d?
I'm in the process of moving a 2d top down game I've been working on into a proper rigid body physics engine like Farseer. Up until now, I had just hacked together my own physics code where needed.
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vote
5answers
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What is the proper way to remove a box2d body from the world in libgdx?
I'm wondering how to remove the body from the world, because I found an error when I tried.
I found following error.
java:
...
7
votes
1answer
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Basic Box2D collision detection
I don't understand how to listen for collisions in Cocos2D/Box2D. Say I have two dynamic circle bodies. One is very small and the other is relatively large. When the small circle collides w/ the ...
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3answers
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Polygon/Shape definition changes in Box2D 2.1
I was going through a pretty good tutorial on Box2D here, but I ran into a problem when he made a b2PolygonDef, because the tutorials were made in 2.0, and I'm using 2.1. I could download 2.0 I guess, ...
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3answers
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Semi Fixed-timestep ported to javascript
In Gaffer's "Fix Your Timestep!" article, the author explains how to free your physics' loop from the paint one.
Here is the final code, written in C:
double t = 0.0;
const double dt = 0.01;
double ...
2
votes
1answer
442 views
Stopping on a slope in Box2d
I am creating a simple platformer using Box2d. I've implemented a variant of the technique described here.
To make the player character move more 'platformer-like' I want him to stop on (shallow) ...
1
vote
1answer
940 views
Box2D platformer movement. Are joints a good idea?
So i smashed my brains trying to make my character move. As i wanted later in the game to add explosions and bullets it wasn't a good idea to mess with the velocity and the forces/impulses didn't work ...
5
votes
3answers
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How to remove a box2d body when collision happens?
I’m still new to java and android programming and I am having so much trouble Removing an object when collision happens.
I looked around the web and found that I should never handle removing BOX2D ...
4
votes
2answers
207 views
Detecting a ledge in Box2D [duplicate]
Possible Duplicate:
Detect Open Space in Farseer
How do I detect ledges?
I'm making a 2D platformer with Box2D. The player needs to be able to grab onto a ledge and pull him/herself up.
...
4
votes
1answer
353 views
Cocos2d: Tongue effect like in Munch Time
I'm wanting to do a tongue effect for my character like the one in Munch Time( shown in pic ). The player does some action and his tongue attaches to the nearest platform.
I'm thinking this is ...
4
votes
3answers
535 views
IndexOutOfRangeException on World.Step after enabling/disabling a Farseer physics body?
Earlier, I posted a question asking how to swap fixtures on the fly in a 2D side-scroller using Farseer Physics Engine. The ultimate goal being that the player's physical body changes when the player ...
3
votes
3answers
181 views
Libgdx body passing through block then fall on it
I'm using libgdx and its physic engine Box2d. My question is : how could I make my box2d body go through a block , ignore the first collison than make the block active so the ball can fall onto it. A ...
2
votes
1answer
206 views
How to make a character in a Box2D world jump faster?
I have a question about using Box2D to simulate a physics-platformer.
I manage to make the character move to the right and left, and jumping as well. However, jumping seems extremely slow when ...
2
votes
1answer
269 views
How do I make a rope from point A to B in Box2D?
I need to make a rope (preferably not elastic) from one point to the next in Box2D. If it helps, I'm trying to develop one of those 2D Spiderman games, like this: ...
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vote
2answers
305 views
What is the Box2D coordinates system?
I know that for Box2d I need to translate pixels to meters which is easy peasy. However my problem is what is the orientation of Box2D coordinates system? Is this the same as screen one (right += x, ...
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vote
3answers
663 views
Unable to find good parameters for behavior of a puck in Farseer
EDIT:
I have tried all kinds of variations now. The last one was to adjust the linear velocity in each step: newVel = oldVel * 0.9f - all of this including your proposals kind of work, however in the ...
1
vote
1answer
998 views
Making an object swing from one rope to another
I am trying to make a Tarzan like game with Cocos2D and Box2D. I am having issues with the physics - making an object swing from one rope to another. I am not really sure how to do this. Could anyone ...
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vote
2answers
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Box2D Platform body not moving player body along with it
I am creating a game using Box2D (Javascript implementation) - and I added the ability to have a static platform, that is moved along an axis as a function of a sine.
My problem is when the player ...
0
votes
1answer
352 views
AS3: limit objects to stage width?
I want to limit the creation of objects acording to the stage width.
My method is the following:
for (var i:int = 0; i<7; i++){
If I put something like this, it won't work
for (var i:int = ...
