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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What is your Unity 3D physics engine budget for iOS games? [closed]

I'm testing Unity for a game that I'm building, and I've touched its limit. My test scenario: a wanna-be house with 200 elements (cubes rescaled) no textures, box colliders and rigid bodies for each ...
0
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1answer
345 views

How do I rotate a segment + normal so that the normal is (0,-1) and the segment is now axis aligned

I have an arbitrary line segment, which may or may not be axis aligned along with its normal eg: Segment(Coord(-1,-1), Coord(1,1), Coord(-1, 1).normalize) which represents a line segment with a 45 ...
2
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1answer
3k views

in Unity3d, how to automatically create fixed joints in a wall of cubes?

I want to create a wall: width 6 cubes height 7 cubes therefore I have 22 cubes on the margins and 20 cubes inside. For each of the margins cubes(except the corners) I have to set 3 fixed joints, ...
4
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2answers
266 views

Controls for physics-enabled game object

I'm trying to put together 2D game on Flash ActionScript. Game objects positions are updated by physics library and I'm trying to control them applying forces and updating these forces every frame. ...
5
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1answer
866 views

Havok physics with a wide range of object scales

So typically Havok works best with normal human sized objects with a gravity of 9.8m/s^2 and dealing with everything in meters. In my Game though there will be a large variety of scales from ...
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3answers
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Web workers for HTML5 game physics simulation?

A bit related to this question. The idea is to guarantee the same physics behavior as much as possible. Would it be possible to run fixed time step physics on a web worker? The UI would update ...
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5answers
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Why do objects interpenetrate in this simple collision solver?

The code below is from a Microsoft XNA sample here. This is quite a simple rigid body simulation that ignores many physical effects (such as angular momentum), but it does try to push objects ...
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4answers
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Physics engine recommendation which can simulate pool game correctly? [closed]

I'm making a pool-game like game. This game requires correct (or very accurate) reflective bounces. I tried Box2D and Bullet Physics, but they both have this problem. If there is a wall on top of ...
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0answers
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How can I make bodies that do not stick to the wall in Bullet Physics? [duplicate]

Possible Duplicate: Physics engine recommendation which can simulate pool game correctly? I made a Billiards scene with Bullet Physics, but I've got a problem. When the ball is slowing down ...
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3answers
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Can I change shape of a rigid body after it created in Bullet3D?

I'm beginning Bullet3D. Can I change collision shape of a rigid body after it created? A rigid body accepts a collision shape when it's creating, but it's hard to find options changes the collision ...
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3answers
562 views

Gravity strength in first person games

In our game, we set the acceleration due to gravity to the appropriate value of 9.8 m/s^2. Although physically correct, it feels more like moving around on the moon.. It feels about right at a value ...
5
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1answer
243 views

Splitting an object into two

I'm using Farseer physics engine. I have a simple rectangle body and would like it to split into two pieces given a starting coordinate (where the bullet enters the object) and ending coordinate ...
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3answers
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2d Collision detecton axis aligned boxes

I have recently run into some trouble with my collision detection. My game is composed of a map made out of axis aligned squares. The player has an x and y velocity, and I want to know how I can find ...
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vote
1answer
249 views

Mouse joint isn't restricting the ball from going to the other part of the screen

I'm developing a application in cocos2d using the Box2D framework, but unfortunately I am having issues. I'm not able to restrict the orange ball in the half screen area, taking the image below as ...
0
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2answers
254 views

How to apply numerical integration on a graph layout

I've done some basic 1 D integration, but i can't wrap my head around things and apply it to my graph layout. So, consider the picture below: if i drag the red node to the right, i'm forcing his ...
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1answer
4k views

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 ...
8
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1answer
656 views

Finding the point of collision

I'm writing a 2D rigid body simulator. The objects being simulated are convex polygons. My question involves how to decide on the "point" of collision, so that when I apply a response force, I can ...
3
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2answers
1k views

When and how should I apply forces in a Cocos2D + Box2D game?

I have some small circles just rolling across the bottom of the screen in my Cocos2D/Box2D iOS app. The bodies are dynamic... so I make them roll by applying a horizontal force to the center of mass ...
12
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4answers
1k views

Animated examples of different interpolations formulas: any link? [closed]

I remember having spotted a link to a huge page with different equations to non linear interpolation curves, for example if you want to stop a car smoothly, etc. Those can sometime be useful to ...
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2answers
1k views

Physics for a 2.5D platformer with a plane that curves

I'm creating a 2.5D platformer in XNA which uses 3D models that are constrained to travelling along a 2D plane (just like Trine). To make things tricker, however, I want the 2D plane itself to be ...
9
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1answer
2k views

Adding air drag to a golf ball trajectory equation

I'm developing a 2D golf game in VB.NET 2005, but I am stuck on how to implement air or wind drag that should affect the ball. Already I have these equations for projectile: Vo ...
8
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3answers
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Kepler orbit : get position on the orbit over time

I'm developing a space-simulation related game, and I am having some trouble implementing the movement of binary stars, like this: The two stars orbit their centroid, and their trajectories are ...
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2answers
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Why are my objects becoming permanently stuck to walls using Box2D?

I setup a simple simulation environment something like billiards. There are four circle balls (dynamic) and four box walls (static). Simulation works... except one thing. Sometimes when a ball rest ...
4
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1answer
263 views

Box2D stable range and position

Box2D marks stable range of object size is 0.1M ~ 10M. This specifies object size range. How about space size? If I make an 1M object at (1000.0f,1000.0f) position? Is it can be stable? Or should I ...
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vote
1answer
3k views

Best 3D Physics Engine to use with Ogre [closed]

I am looking for a good physics engine to use with an Ogre game I'm writing. I would prefer for it to be free, open source, mature, simple to use, easy to learn, and flexible. I'm currently thinking ...
3
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2answers
433 views

Silverlight scrolling with camera

I'm trying to get my head around scrolling a 2D map that uses a physics engine. If I was to launch a projectile, would I actually be applying the physics to the background images rather than the ...
3
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1answer
516 views

Maximum range of projectile fired at given force and elevation

I've gone over this again and again, and my result is obviously wrong when viewed in-action. Here's the initial formula I converted (first one): http://en.wikipedia.org/wiki/Range_of_a_projectile ...
6
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1answer
865 views

Pseudo-magnet implementation with chipmunk

How should I go about implementing "natural" magnet on a certain body in chipmunk space? Context is of simple bodies lying in the space (think chessboard). When one of the figures is activated as a ...
6
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2answers
2k views

How to make bird to fly using box2d

I am new to Box2D, I have set gravity to 10. How to make an object fly in space even though the gravity is 10. What are the properties I need to set to make object fly? Is there any different ...
2
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2answers
364 views

I'm looking for a paper from Teknikus.dk

I'm looking for this great paper about Verlet integration: http://www.teknikus.dk/tj/gdc2001.htm I've found this link on many websites, forums, blogs, everyone is recommending it ! The website is ...
4
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2answers
507 views

Particle and Physics problem

This was originally a forum post so I hope you guys don't mind it being 2 questions in one. I am making a game and I got some basic physics implemented. I have 2 problems, 1 with particles being ...
4
votes
1answer
380 views

Good book or tutorial for learning how to apply integration methods [closed]

I'm looking to animate a graph layout using edges as springs and nodes as weights (a node with more links will have a bigger weight). I'm not capable of wrapping my head around the usage of ...
4
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1answer
854 views

Angular Velocity

Hey, I have a particle that is hit with a force F at a particular position on the ball P. How can I calculate the angular velocity of the X,Y and Z axis? The actual rotating of the object should be ...
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4answers
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Physics timestep questions

I've got a projectile working perfectly using the code below: //initialised in loading screen 60 is the FPS - projectilEposition and velocity are Vector3 types gravity = new Vector3(0, ...
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votes
2answers
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Find meeting point of 2 objects in 2D, knowing (constant) speed and slope

I have a gun which fires a projectile that has to hit an enemy. The problem is that the gun has to be automatic, i.e. - choose the angle in which it has to shoot, so that the projectile hits the enemy ...
2
votes
1answer
637 views

Calculate the initial velocity of a 3D trajectory

I've got a 2D projectile code sample working, but would like to extend it to 3D. How would I calculate the initial velocity of the Z-axis? At the moment, I've got: initVel.X = (float)Math.Cos(45.0); ...
9
votes
2answers
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Simulating an object floating on water

I'm working on a top down fishing game. I want to implement some physics and collision detection regarding the boat moving around the lake. I would like for be able to implement thrust from either the ...
3
votes
3answers
387 views

Adding 'swerve' to a direction

I'm not much of a maths expert, so this is probably quite straight forward. I was playing a soccer flash game where you take free kicks. You provide Power, Swerve and Direction. I'm reading up on ...
7
votes
5answers
979 views

Is it possible to have vehicles with physics like GTA in an MMO game?

I haven't seen any MMO games with vehicles with realistic physics and that could achieve high speed, why? Is it because of network bandwidth limitations? Second Life has vehicles, but physics are ...
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4answers
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How to build a bones animation engine?

I want to develop a flash game. It would draw a stick man, and edit his pose. I think what I need to learn are bones animation and physics engine. Can anyone introduce some good resources to learn ...
3
votes
1answer
351 views

Approximating walking physics via simpler sliding physics

I am modeling walking insects. I implement them as cuboids and use forces (including friction and drag), to control motion. However, the movement characteristics of this 'sliding box' physics don't ...
2
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2answers
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Using box2d DrawDebugData with multi layer scene?

In my Game, a Scene is composed by several layers. Each layer has different camera transformations. This way I can have a layer at z=3 (GUI), z=2 (Monsters), z=1 (scrolling background), and this 3 ...
1
vote
1answer
208 views

2D Game Physics: How to evaluate when an accelerating ray is close to a point?

Given a ray in a 2D world at position p with initial velocity u and acceleration a how can I tell when it's within a certain distance r from a certain point.
1
vote
1answer
602 views

How to use the chipmunk physics-engine?

I am developing a game demo where I want a physics simulation with balls and obstacles. I know that this is possible with the chipmunk physics-engine but I don't know how to use it. Can anybody give ...
14
votes
1answer
3k views

Any fixed-point portable open-source 3D physics engines?

I'm looking for a fixed-point 3D physics engine (basic kynematics and collision detection-resolution... nothing too fancy.) I need fixed-point math because I'd like to have deterministic results, for ...
1
vote
2answers
3k views

Voronoi regions of a (convex) polygon

I'm looking to add circle-polygon collisions to my Separating Axis Theorem collision detection. The metanet software tutorial (http://www.metanetsoftware.com/technique/tutorialA.html#section3) on ...
12
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1answer
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Separating physics and game logic from UI code

I'm working on a simple block-based puzzle game. The game play consists pretty much of moving blocks around in the game area, so it's a trivial physics simulation. My implementation, however, is in ...
18
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6answers
2k views

AI control for a ship with physics model

I am looking for ideas how to implement following in 2D space. Unfortunately I don't know much about AI/path finding/autonomous control yet. Let's say this ship can move freely but it has mass and ...
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0answers
227 views

Simple project - make a 3D box tumble and fall to the ground [duplicate]

Possible Duplicate: Resources to learn programming rigid body simulation Hi guys, I want to try learning rigid-body dynamic simulation. I have done a fluid and cloth simulation before, but ...
3
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1answer
701 views

Breakout clone, how to handle/design for collision detection/physics between objects?

I'm working on a breakout clone, and I wish to create some realistic physics effects for collision - angles on the paddle should allow the ball to bounce, as well as doing curve balls etc. I could use ...