Tagged Questions

15
votes
6answers
5k views

Are there any alternative JS ports of Box2D?

I have been thinking about creating a top down 2D car game for HTML5. For my first game I wrote the physics and collisions my self but for this one I would like to use some ready made library. I ...
6
votes
2answers
758 views

Scrolling Box2D DebugDraw

I'm developing a game using Box2D (javascript implementation - Box2DWeb), and I would like to know how I can pan the debug draw. I know the usual answer is - don't use debug draw, it's just for ...
4
votes
2answers
3k views

Box2dWeb and Images

How do I import and attach a PNG or GIF to a shape in Box2dWeb? The best resource I could find online is at: http://www.jeremyhubble.com/box2d.html However, this "tutorial" doesn't give much ...
4
votes
1answer
98 views

How to detect whether an Object came to sleep at a specific position?

I'm currently writing a small game with box2dweb and I need some direction for this: I'm throwing a Box and have to hit a specific place and trigger an event when the object that's been thrown isn't ...
4
votes
1answer
325 views

box2d with lines

I have a very simple platform game builder and I've specified the ceilings, walls and floor as line segments. A line has a winding, or normal; you can determine the direction that a line should be ...
3
votes
3answers
319 views

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
160 views

Box2D: Asteroids-Like Spaceship Physics

I'm new to Box2D (JavaScript) (and the world of physics/mathematics) so I'm having a hard time working out the methods I need to use to make a spaceship act like it does in the classic arcade game ...
2
votes
1answer
879 views

Specifying force and angle in ApplyImpulse in box2d

I need to apply an impulse on a object with a particular force and at a particular angle in Box2d. If I am right the syntax would be the following: body.GetBody().ApplyImpulse(new ...
0
votes
1answer
111 views

Basic Use of ApplyImpulse

I am trying to apply a force to a bunch of b2_dynamicBodys, but it seems to only work for a random number of items and then stops with an error. //create some items to move bodyDef.type = ...
0
votes
0answers
55 views

Impact js Multibody entities with animations

I have a simple impactjs project working with box2d. just a "car" that can run over some rough terrain. I would like to have the wheels spin though. I know I could accomplish this with a sprite sheet ...
0
votes
2answers
247 views

Increasing speed of circle over time as linear with Box2d

Assume that there is a circle and it can be moved by using keyboard arrows.Is required that increasing speed over time like increasing car speed. For example; max speed is 25 and time to reach max ...
0
votes
1answer
85 views

Questions for QueryAABB

I'm currently having trouble getting my head around QueryAABB, and hope to find some answers here. The LowerBound of an AABB the upper-left corner (and vice versa). Why is that and what idea is ...
-1
votes
1answer
376 views

Attach my sprite with Box2d [closed]

I'm coding Javascript(HTML5) with Box2D. And I want to ask how to attach Sprite with Box2D. This is function My sprite: function My_Sprite() { this.m_Image = new Image(); this.m_Position = ...
-1
votes
1answer
141 views

Interacting with box2D objects

How can I interact with an object in box2d, I'm completely new to this so I have no clue what to do. The box is created like this: bodyDef.type = b2Body.b2_dynamicBody; fixDef.shape = new ...