Relating to the motion of objects through space (in 2 dimensions (x,y)) and time. Including concepts such as acceleration (thrust and gravity), mass, collision response, friction and more.

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3
votes
1answer
603 views

Creating a frozen bubble clone [closed]

This photo illustrates the environment: http://i.imgur.com/V4wbp.png I'll shoot the cannon, it'll bounce off the wall and it's SUPPOSED to stick to the bubble. It does at pretty much every other ...
3
votes
1answer
415 views

2D Motocross physics

I'm looking into making a 2D motocross bike game with plausible physics. It should look like this: For a first try, I've created only the player (a motocross driver) and the map (consisting of ...
3
votes
1answer
362 views

Fluid Particle Grid

So recently I have been looking at some fluid simulation techniques, specifically Smoothed Particle Hydrodynamics. One of the key components is a grid to avoid O(n^2) searches. I have been having some ...
1
vote
0answers
377 views

Why won't my Box2d bodies collide? [closed]

I'm doing something wrong when trying to get bodies to collide using jBox2d & Slick2d. Here is have just my basic init, update, and render methods. Render and update seem to work fine for drawing ...
0
votes
2answers
303 views

Making The Player Stop Bouncing And Stop Sinking In The Ground In A Platformer XNA

Heres a problem i've been having. I have a platformer, and whenever my player hits the ground he keeps bounding. Here's the falling code iceBoy.moveY++; iceBoy.position.Y += moveY; Now heres the ...
2
votes
1answer
470 views

Simple 2D hair simulation/manipulation

I would like to simulate very simple hair in a 2D environment, and will need to be able to "brush" the hair. What I want to do: A 2D character is facing squarely towards the player. The player can ...
1
vote
2answers
170 views

limiting jump forces to achieve a maximum jump height [duplicate]

A player and the world are modeled using a physics engine. Jumping is modeled by applying a vertical upward force to the player's physics body when the jump button is pressed. The upward force is ...
16
votes
6answers
9k views

How do I build a 2D physics engine? [closed]

The most advanced games I've made are a 8-ball pool game made with the physics engine Box2dFlashAS3 and a platform game with levels. When I did platform games, I've always wished to know how to make ...
1
vote
1answer
317 views

Debug Render In Cocos2d Android

I want to implement debug render for cocos2d android.So I can view how bodies are created. Right now I use gdx.jar file for box2d and load that jar file following way. static { ...
-1
votes
1answer
125 views

Bullets Spawning in same direction [closed]

I'm using XNA to make a Bullet Hell Shooter game, and I'm running into some troubles when I try to change the direction in which the bullets move. Been trying to debug for awhile, but haven't gotten ...
1
vote
1answer
310 views

Am I implimenting a sweep and prune broadphase correctly? [closed]

The code that I am using is: std::vector <PhysicsBody*> physicsChildren; //containing all objects ... std::sort(physicsChildren.begin(), physicsChildren.end(), sortByLeft); ...
1
vote
2answers
191 views

Collision detection for Monotouch [closed]

What I want to have for my Monotouch 2D projects: simple collision detection and collision polygons working with UIViews Sounds simple, isn't it? I've evaluated a lot of engines available on the ...
0
votes
2answers
85 views

Checking bounds of a quad

I want to know how would I tell if a quad touches another quad in my game built in Slick2D. I have a class that I named "Bounds" which has 4 "Point" objects which just store an X and a Y value and a ...
5
votes
2answers
604 views

Whats the physics behind the doodle jump game?

I'd like to know how we can achieve the doodle jump type physics using andengine. I mean the character is not colliding with the ground blocks when he moves upwards but will collide when he came ...
1
vote
1answer
402 views

In 2d game logic, should I use pixels or world coordinates?

Currently in my game I handle the logic (collisions, movement) using pixels but I find it very limiting espiecially when thinking about variable speed. For example Box2D requires you to use ...
13
votes
3answers
1k views

Powder games: how do they work?

I recently found these two gems: http://powdertoy.co.uk/ http://dan-ball.jp/en/javagame/dust/ My question is: How are the physics with so many elements efficiently handled? Am I just severely ...
1
vote
2answers
186 views

Distribute circles evenly on Screen - circle packing

I want to evenly distribute a random amount of circles with random diameter on the screen for. This level doesn't scroll so the users screen resolution sets the limits. Further I would like the ...
2
votes
1answer
162 views

Physics movement prediction is way off [closed]

I'm making a simple, non-networked game. There are two players and a ball. In implementing the AI for the second player, I've run into a huge problem predicting where the ball will hit the ground. ...
20
votes
7answers
2k views

Optimizing gravity calculations

I've got a bunch of objects of varying size and velocity which gravitate towards each other. On every update, I have to go over every object and add up the forces due to gravity of every other object. ...
1
vote
1answer
131 views

Increase restitution (bounciness) of an object in a JavaScript formula

I'm going slightly around the houses on this one. I originally started a thread over on Stack Overflow about it but then it seemed to diverge into mathematics, with no joy from the SO community over ...
12
votes
3answers
2k views

Resolving a collision with forces

In my 2D physics engine, I can detect AABB vs AABB collisions, and resolve them by finding the shortest penetration vector and adding it to the AABB's position. Doing this "pushes" the first AABB ...
1
vote
1answer
489 views

Collision detection against specific sprite shape using XNA with Farseer Physics?

I am making a 2D XNA Game, using Farseer Physics for collisions. I need collisions to be resolved against the actual shape of the sprite image, ignoring transparent pixels, rather than against the ...
5
votes
2answers
523 views

Ball bouncing infinitely and constantly

Alright, so I've got hold of some simple physics mechanics, and am currently trying to implement bouncing. Based on the first answer of this question, I've developed the following algorithm: ...
-2
votes
1answer
119 views

Help finding a good XNA physics library? [closed]

I'm looking for a good physics library for XNA. Can anyone help me find something good, simple and easy to learn for XNA?
1
vote
2answers
2k 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 ...
2
votes
2answers
895 views

Non-physics character movement in a Box2d Environment

I am in the process of creating a physics platformer. However, I want the player movement to feel very old-school(as in: non-physics like), which means that the character: Should always move equally ...
1
vote
2answers
504 views

Find the Contact Normal of Rectangle Collision

It seems a lot of people have asked similar questions on this site, and every time it seems like a whole bunch of answers that don't work are given. Basically, I have two rectangles (AABBs) that ...
0
votes
1answer
140 views

Separating Axis Theorem fails at certain angles

I'm currently attempting to add an overlap tester for an axis aligned and orientated bounding box but the solution only seems to work accurately when the OBB's angle is between -10 and +10. As the ...
0
votes
2answers
139 views

Circle Collision class not positioning itself correctly

Ok I am using unity3D and the Futile framework. I have everything drawing and working correctly with Futile, but I am trying to attach a circle collision class to the FSprite that I have. I must be ...
1
vote
1answer
247 views

What physics engine support force fields and bodies represented as points?

I need a game engine that supports force fields in 2d or 3d, but suitable for 2d calculations, like bullet. Each body I want to simulate is represented as a set of points. Each point has positive ...
-3
votes
1answer
269 views

Implementation of planets in top-down space shooter [closed]

I am working on a top-down space shooter, and I have come to the point where I need some input on a mechanic. I have implemented enough that I can make this choice; either way will not change the code ...
8
votes
1answer
299 views

Calculate bike heading from front wheel heading and velocity

I have a simple top down bike game that I'm trying to add steering to. I would like to know how I use the heading of the front wheel to determine the heading and velocity of the bike. void Update () ...
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 ...
5
votes
1answer
210 views

Physics/Logic behind self-bounce

I have a game that I am currently working on and I have a problem. What would a ball look like when it makes itself bounce. Say, for example that the ball had its own "inner power", was made out of ...
4
votes
2answers
693 views

Tracking Object Position - Firing on a Trajectory

How can I calculate the position of an object after "firing" it from a fixed point? I am to create a small game - most likely with canvas (pure HTML, JS based) or Adobe Flash - in which the player ...
7
votes
1answer
275 views

How do engines avoid “Phase Lock” (multiple objects in same location) in a Physics Engine?

Let me explain Phase Lock first: When two objects of non zero mass occupy the same space but have zero energy (no velocity). Do they bump forever with zero velocity resolution vectors or do they ...
9
votes
3answers
619 views

Impulsioned jumping

There's one thing that has been puzzling me, and that is how to implement a 'faux-impulsed' jump in a platformer. If you don't know what I'm talking about, then think of the jumps of Mario, Kirby, and ...
13
votes
2answers
4k views

2D Planet Gravity

I'm trying to make a simple game where a spaceship is launched and then its path is effected by the gravity of planets. Similar to this game: http://sciencenetlinks.com/interactives/gravity.html I ...
3
votes
1answer
372 views

2D Smooth Turning in a Tile-Based Game

I am working on a 2D top-view grid-based game. A ball that rolls on the grid made up of different tiles. The tiles interact with the ball in a variety of ways. I am having difficulty cleanly ...
1
vote
2answers
2k views

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 ...
10
votes
3answers
448 views

How to simulate pressure with particles?

I'm trying to simulate pressure with a collection of spherical particles in a Unity game I'm building. A couple notes about the problem: The goal is to fill a constantly changing 2d space/void with ...
4
votes
4answers
669 views

Point of contact of 2 OBBs?

I'm working on the physics for my GTA2-like game so I can learn more about game physics. The collision detection and resolution are working great. I'm now just unsure how to compute the point of ...
2
votes
2answers
267 views

Procedural generation of physics-enabled structures (in a 2D world)

Is it possible to procedurally generate stable structures out of rigidbody objects at a reasonable runtime speed? Imagine Angry Birds's levels kind of structures but generated procedurally.
1
vote
3answers
416 views

Implementing distance joint

I would like to implement something that behaves much like a distance joint / revolute joint in Box2D, however I do not want to throw a whole physics engine at this problem. I'm curious where I might ...
1
vote
1answer
226 views

What is going on in this SAT/vector projection code?

I'm looking at the example XNA SAT collision code presented here: http://www.xnadevelopment.com/tutorials/rotatedrectanglecollisions/rotatedrectanglecollisions.shtml See the following code: private ...
27
votes
11answers
5k views

Do 2D games have a future? [closed]

I'm currently working on a 2D soft-body physics engine (since none exist right now -_-), but I'm worried that there's no point to spending what will most likely be years on it. Although I love ...
12
votes
3answers
3k views

2D game collision response: SAT & minimum displacement along a given axis?

I'm trying to implement a collision system in a 2D game I'm making. The separating axis theorem (as described by metanet's collision tutorial) seems like an efficient and robust way of handling ...
62
votes
5answers
24k 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
1answer
219 views

Game Physics: Implementing Normal Reaction from ground correctly

I am implementing a simple side scrolling platform game. I am using the following strategy while coding the physics: Gravity constantly acts on the character. When the character is touching the ...
0
votes
1answer
246 views

How to implement physical effect, perspective effect on Android

I'm researching about 2D game for Android to implement an Android Game Project. My project looks nearly like PaperToss. Instance of throwing a page, my game will throw a coin. Suppose that I have a ...