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

learn more… | top users | synonyms

4
votes
5answers
6k views

Box2D physics editor for complex bodies [closed]

Is there any editor out there that would allow me to define complex entities, with joins connecting their multiple bodies, instead of regular single body entities? For example, an editor that would ...
4
votes
3answers
651 views

Designing the main classes in a solar system simulation game in C++

If this is not the right place for this question, could you please direct me to a more suitable site/forum? I'm a beginner in game development (and in the use of this site). I've worked with C++ only ...
4
votes
1answer
226 views

How do I make a cube move by rolling?

I am learning jMonkeyEngine by making some small games with it. I have a simple rectangular cube that I want the player to be able to roll around the game world. When he presses the arrow keys, the ...
4
votes
2answers
388 views

Why are we not using integers in game physics?

We can use integer for game physics (or without physics, simply object representation): mass, position and rotation, where the integers represent, for example, the number of milligrams, millimeters or ...
4
votes
3answers
152 views

Particle dynamics simulation and conservation of energy

Suppose you want to simulate the dynamics of a particle subject to Newton's laws of motion. We could just fix a discretization of the time dt and solve approximate differential equations like ...
4
votes
2answers
1k views

How to achieve smooth gameplay in a physics based multiplayer game? (2d)

I'm using cocos2d 2.0 and Gamekit for networking. I've got a server/client model. It works over wifi (local) and bluetooth. (Xcode 4.3, Objective C) Basically, there's a ball and 2 or more players. ...
4
votes
5answers
955 views

Is knowing physics necessary for game development?

Is knowledge of physics necessary to design quality games? How important is it? Be realistic and explain a few novice examples of how's mandatory. What kind of physics is necessary, ...
4
votes
3answers
776 views

Problem representing torque as a quaternion

Euler angles are much more intuitive to me than quaternions for representing 3-dimensional rotations. In fact, I barely understand quaternions at all. I use quaternions for rotation because people ...
4
votes
2answers
1k views

Calculating the angular direction from velocity

I'm trying to calculate the angular direction of a projectile, knowing it's X and Y velocity I can find the magnitude of its movement, but I'm having a hard time wrapping my mind around getting the ...
4
votes
4answers
451 views

The physics equation for a perpetual seesaw

I am trying to create a game that involves two or more people jumping on a seesaw and propelling each other in the air. I need help with the physics equations Assume no friction and no air ...
4
votes
1answer
191 views

How do I make a tile passable in one direction only?

I want that my character can jump through some of the tiles, like Mario does in this video: http://www.youtube.com/watch?v=zIPYzbNrNhc In this video, Mario jumps up through orange platforms, but ...
4
votes
1answer
169 views

What is the appropriate way to implement collision in 2D worlds?

If I want to create a 2D game map which features areas traversable by a player through standard up/down/left/right inputs, and then have areas that are NOT traversable... perhaps just a bush, or a ...
4
votes
1answer
415 views

Splitting logic into threads in Java tower defence game

I'm making a tower defence game in Java! It's my first game development. I want to know how many threads Do I need to create in a game, to split logic.. I've made this one: Main App thread (adds ...
4
votes
3answers
1k views

Quaternion dfference + time --> angular velocity (gyroscope in physics library)

I am using Bullet Physic library to program some function, where I have difference between orientation from gyroscope given in quaternion and orientation of my object, and time between each frame in ...
4
votes
1answer
385 views

How to balance a ball on a rotating plane?

I'm doing some research and I really don't want a physics engine when a simple mechanism will do. I have a ball that will be balanced on a plane. The ball will always be "stuck" to the plane and ...
4
votes
2answers
250 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. ...
4
votes
3answers
207 views

How do I resolve a sphere-triangle collision in a given direction?

I am trying my hand at game physics. I understand that the basic way to pull back a sphere when it collided is to negate the penetration distance: // If collided... // `distance`: distance form ...
4
votes
2answers
247 views

Game physics presentation by Richard Lord, some questions

I been implementing (in XNA) the examples in this physics presentation by Richard Lord where he discusses various integration techniques. Bearing in mind that I am a newcomer to game physics (and ...
4
votes
1answer
489 views

Making AI jump on a spot effectively

How to calculate, in 3D environment, the closest point, from which an AI character can jump onto a platform? Setup I have an initial velocity V(Vx,Vy,VZ) and a spot where the character stands still ...
4
votes
1answer
7k views

How to detect collision in Unity3D without rigid bodies?

The target platform of my game is mobile devices therefore I try to develop it performance oriented. It will be a strategy game so I don't really need physics in it, consequently I did not add ...
4
votes
1answer
852 views

Efficient physics and collision detection for RTS

I'm thinking about writing my own RTS game and while I'm more or less clear about how the game engine should work, I need some directions as to how to implement physics and collision detection. Now, ...
4
votes
1answer
694 views

How to make an object fly out of a slingshot?

At the moment I'm improvising a slingshot, the user can click and drag the projectile and let go. The force on the object is calculated by getting the distance between the vector of the slingshots two ...
4
votes
4answers
2k views

Which Side Was Hit?

I am working on an Android game and I have two objects A and B (both rectangles) and when they collide I simply want to know which side of B was hit. I have detected the collision fine, but I am ...
4
votes
3answers
507 views

How can I model the physics of an air blower?

I want to model simple lottery machine, it has got a bottom blower. Do you know how can I get force applied to object above blower by air from blower, or equations to model this behavior? Red ...
4
votes
1answer
143 views

Correct order of tasks in each frame for a Physics simulation

I'm playing a bit around with 2D physics. I created now some physic blocks which should collide with each other. This works fine "mostly" but sometimes one of the blocks does not react to a collision ...
4
votes
3answers
256 views

Programming atmosphere for game

I've recently started making game and I want to implement there an atmosphere. My plan is to include in game many compartment, tubes and ventilations. For example if I open and airlock from room with ...
4
votes
2answers
410 views

Simulate forces on a connected chain

I'm building a 2D space game where the player uses a chain to grab on to nearby asteroids. The asteroids move along a specific path with a constant velocity. The chain has a maximum length L and ...
4
votes
1answer
310 views

Techniques for displaying vehicle damage

I wonder how I can displaying vehicle damage. I am talking about a good way to show damage on screen. Which kind of models are common in games and what are the benefits of them? What is state of the ...
4
votes
1answer
300 views

How to synchronise the acceleration, velocity and position of the monsters on the server with the players?

I'm building an MMO using Node.js, and there are monsters roaming around. I can make them move around on the server using vector variables acceleration, velocity and position. acceleration = ...
4
votes
1answer
961 views

Effects of collisons: broken glass, damaged cars, how are they created?

My question is related in particular to achieving the effects of collision in game engine, how is this done? I have searched a bit, read from the internet and went through a few tutorials, and saw ...
4
votes
1answer
541 views

Problem with impulses in my physics engine

I'm currently developing a small 3D impulse-based physic engine for a CS project. It uses GJK for collision detection and is kind of stable at the moment. Nevertheless, I'm not satisfied with my ...
4
votes
4answers
984 views

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, ...
4
votes
3answers
652 views

What do I need to change in Box2D to work in pixels?

Box2D seems to be set up in such a way that you cannot work in pixels (i.e. physics scale = 1). It produces very strange results as it hits maximum speed limits at low speeds and looks very strange. ...
4
votes
2answers
159 views

2D Enemy AI reacting to sound

I'm currently working on a 2D top-down survival game and I'm trying to figure out a good method for enemies to detect player sounds. For instance - if the player fires his gun it should play a sound ...
4
votes
1answer
783 views

GGX specular BRDF is way over 1!

Now, the classic Torrance derivation for roughened surfaces which Cook took into vectorized form yields the familiar parametrization of a specular BRDF where we have the NDF which decides how much ...
4
votes
1answer
232 views

How display path ball will bounce?

I'm trying to figure out a way to show the path a ball will travel, so that the player can line up a shot before they fire the ball. I can't think of a way to calculate this path in advance and ...
4
votes
1answer
1k views

AndEngine: Density, Elasticity, Friction, Gravity concepts

I am new to AndEngine. I have seen some physics examples from AndEngine Example package. I want to know the role of density, elasticity, friction and gravity while implementing physics. How they ...
4
votes
2answers
438 views

What AI technique should I use to control a car in a bumpy environment?

What kind of AI can you recommend controlling a car in a level where there are hills, sharp turns, straight parts, et cetera? There is AI in the game already. It uses points on the road to which the ...
4
votes
2answers
490 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
367 views

Good book or tutorial for learning how to apply integration methods

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
votes
2answers
1k views

2D game - Missile shooting problem on Android

I have to make a tank that sits still but moves his turret and shoots missiles. As this is my first Android application ever and I haven't done any game development either, I've come across a few ...
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 ...
4
votes
2answers
392 views

Modular spaceship control

I am developing a physics based game with spaceships. A spaceship is constructed from circles connected by joints. Some of the circles have engines attached. Engines can rotate around the center ...
4
votes
2answers
281 views

How to implement homing missiles with loops while in transit?

I have implemented missiles that steer towards a target, however this feels kind of boring. I want to add loops! Loops are cool! To do this I thought I could use catmull-rom splines, but that seems ...
4
votes
4answers
642 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 ...
4
votes
3answers
946 views

Interpolate and collisions

Lets take the simple example of a ball bouncing off a wall. The physics is separated from the display. The physics is set to run at say 20 frames per second and the display is running faster than this ...
4
votes
3answers
646 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 ...
4
votes
2answers
794 views

Simulating the effects of wind

I am developing a mobile game for Android. It is a 3D jumping game (like ski jump) where wind plays a important role so i need to simulate it. How could I achieve this? The game uses libgdx for ...
4
votes
1answer
956 views

How to make a 2D Soft-body physics engine?

The definition of rigid body in Box2d is A chunk of matter that is so strong that the distance between any two bits of matter on the chunk is completely constant. And this is exactly what ...
4
votes
2answers
768 views

Development platform for 2D web and mobile games

Is there a game development platform -- similar to Torque, or Unity -- which can be used to deploy 2D games on the following platforms: Web iOs Android Xbox Live Arcade (Preferred but not required) ...