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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4
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1answer
2k 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 ...
1
vote
1answer
959 views

Need to translate a Rotation Matrix to Rotation y, x, z OpenGL & Jitter for 3D Game

I am using the Jitter Physics engine which gives a rotation matrix: M11 M12 M13 M21 M22 M23 M21 M32 M33 And I need it so OpenGL can use it for rotation GL.Rotate(xr, 1, 0, 0) GL.Rotate(yr, 0, 1, ...
0
votes
0answers
2k views

Platform game: applying gravity and jumping [duplicate]

I am making a 2D platform game in Java but I don't know how to apply gravity and jumping on my player and other living creatures in game that it looks natural and that it is physical correct. I have ...
2
votes
2answers
406 views

Canting of track in a racing game

I am trying to create a small racing game in which the track would be modeled using a BSpline curve for the path's center line and directional vectors to define the canting of the track at each point. ...
0
votes
1answer
479 views

Showing trajectory indicator

From the image you can see that the ball fired on the left that fire behind it, does not match the calculated trajectory. Im drawing the ball trajectory using an equation from a SO question, this is ...
7
votes
2answers
378 views

How to implement a tractor beam?

I'm working on a game where the player can pick up objects using something like a tractor beam, and carry them around. Attracting the object towards the center of the beam is not difficult. But once ...
2
votes
0answers
232 views

How do I compute the angle between a pixel on an irregular curve and a circle colliding with it?

I'm building a custom physics engine to accompany a level-editor. This image shows how the level-editor outputs levels: Now, some explanation is in order. The curve is defined by the red points. ...
0
votes
1answer
238 views

Issues calculating frame independent movement

I'm developing a Breakout style game in C++ using SDL. The problem so far is that the ball slows down and speeds up for no particular reason. The slowdowns usually last a few seconds. EDIT : When ...
3
votes
1answer
772 views

How to implement throw curve with virtual height in a 2D side-view game

I am working on a 2d side-view soccer game that looks like this image: But now I stuck on how to implement parabola pass ball. I have found many questions corresponding to my problem: Calculating ...
2
votes
1answer
724 views

How can I implement a simple “jump” action with three.js and/or Physijs?

Assume I have a simple Physijs object like this car. How can I adapt something like this to "jump" (hydraulics ftw!) when pressing spacebar for instance? I'm currently thinking applyCentralImpulse ...
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votes
2answers
743 views

Move a player in the opposite direction they are looking

I'm looking to move the player in the opposite direction they are facing with a specified force. Rather than try to explain that better I created an image showing what I mean, I've tried reversing ...
9
votes
1answer
465 views

Multiplayer platformer - Are server corrections normally required with a single client on the server?

I am currently working on a rather simple multiplayer platformer. I read quite a bit of articles on the techniques used to hide latency, but I still fail to get my head around certain of the concepts. ...
4
votes
3answers
132 views

Propel entities at some angle (depending on explosion's position)

I have a 2D platformer. There are multiple particles that are just 1x1 colored pixels. Let's assume there are 256 particles laid out as a 16x16 cube. Say I popped an explosion right in the middle. All ...
4
votes
1answer
486 views

Simple 3D collision detection for general polyhedra

I have correctly set up a SAT system. I now need to determine a simple, fast, and general purpose collision detection mechanism to identify the collision points. These points will then be used to ...
3
votes
3answers
2k views

Unity 4 - Some Rigidbodies Won't Fall Asleep

I'm having this problem in the free edition of Unity 4.1 where rigidbodies aren't falling asleep (and yes, I've tried playing with the sleepVelocity and sleepAngularVelocity values!). I've read the ...
8
votes
1answer
3k views

A simple flight simulator

In a 3D flight simulator with a Crimson Skies level of realism (as in, arcade level rather than realistic), how do you determine the movement of an aircraft each game clock tick? (Crimson Skies is an ...
3
votes
1answer
376 views

GPGPU physics & game logic

I'm wondering about gpu accelarated physics after reading about Erwin Coumans presentation on GPU accelerated physics: http://www.gdcvault.com/play/1018185/GPU-Rigid-Body-Rigid-Body (demo video here: ...
1
vote
3answers
975 views

How to move around a player in a curved tunnel?

In a scenario where the player moves freely along the walls of a tunnel (like this), what is the best way to move the player along the walls of the tunnel? I'm using Unity3d game engine. I've tried ...
4
votes
3answers
223 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 ...
0
votes
1answer
240 views

Resolving a collision between point and moving line

I am designing a 2d physics engine that uses Verlet integration for moving points (velocities mentioned below can be derived), constraints to represent moving line segments, and continuous collision ...
0
votes
1answer
1k views

gamemaker getting a ball to bounce 90 degrees off of a 45 angle

I am trying to get a circle to bounce off a 45 degree diamond shap using Gamemaker Studio. I would like the ball to bounce in straight lines so my directions would be 0, 90, 180, or 270 degrees, ...
0
votes
1answer
423 views

How to simulate the movement of a ball in 2D due to force, gravity, and friction with surface?

I have a ball which I kick with some force. It has a starting x,y position, sat (2,3) and an intended target x,y say (7,8) position. That means I have to translate by (7-2, 8-3) i.e. 5 x units and ...
0
votes
4answers
5k views

Smooth jumping in 2D platformers [duplicate]

I have a very simple 2D game, similar to old-school Mario or Metroid. I'm having a lot of trouble figuring out the proper way to handle player jumping. I've tried several different methods. The first ...
2
votes
1answer
264 views

Implementing a time scale in game with fixed physics update

I'm currently putting together my game loop based on the "Fix Your Timestep" article at gafferongames.com. This is going fine, but I'm also trying to implement a 'time scale', i.e. a way to control ...
0
votes
3answers
834 views

Box2D body jitters when colliding with static body

I am developing a game where a body is moved within the scene using touch. The scene has a boundary wall made up of static rectangular bodies. When I move the object along the boundaries, on ...
1
vote
1answer
514 views

Calculating distance by force

I am trying to predict a ball(sphere) movement. The formula of force which I know is Force=Mass*Accelaration What I want is how can I get distance or displacement by giving particular force? I want ...
4
votes
3answers
333 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 ...
2
votes
1answer
373 views

How do I make my camera follow a Box2D object?

I'm implementing a camera in my game. It worked for regular objects, but I began using Box2D and obviously things changed a bit. I have a Body object that I want to draw at the center of the screen. ...
11
votes
0answers
4k views

Creating Rope Physics for Unity [closed]

I want to create a bungee jumping-like game in Unity and therefore I need a rope physics. I especially need elastic ropes with capability to pull objects with velocity after a little extension. Do you ...
1
vote
1answer
1k views

2D Destructible Terrain with Box2D / Cocos2D -> Image Tracing

Bear with me as this will be a rather lengthy post. For the last month I have been working on an open source Cocos2D, Box2D Destructible Terrain Engine. I have some questions regarding its ...
26
votes
5answers
3k views

Simulating pressure in a grid based liquid simulation

I have a 2D grid based water system in my XNA game, we have a method using cellular automata to simulate water falling and spreading. Example of water flowing down a slope: Each tile can contain a ...
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votes
1answer
438 views

How is destructable terrain made in SDL?

I'm looking for terrain that gets removed in chunks (like in Worms, of instance). How do you do this in SDL?
2
votes
1answer
533 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 ...
1
vote
1answer
433 views

How should I invoke a physics engine?

I'm new to writing games. I'm planning to write a 2D battle game which may require an physics engine. Suppose I've written one, but how can I combine it with the main routine of my game? Should I ...
1
vote
1answer
1k views

Box2d contant speed before and after collision

I want to make my body fly at constant speed, how to make it fly at constant speed before and after collision? I set restitution of my body to 1.0 but after some direct and powerful collisions my ...
5
votes
2answers
607 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 ...
3
votes
1answer
534 views

Sensor based vs. AABB based collision

I'm trying to write a simple collision system, which will probably be primarily used for 2D platformers, and I've been planning out an AABB system for a few weeks now, which will work seamlessly with ...
4
votes
2answers
393 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 ...
0
votes
1answer
850 views

Detect when a bullet rigidbody is on ground

I have a rigidbody that is on top of a plane or another rigidbody. How do I check if said rigidbody is on top of it? I tried to check the Y-part of the velocity but it is never 0, it is always a ...
3
votes
0answers
134 views

How to make the Angry Birds “shot arch” dotted line? [duplicate]

I am making a game that includes 2D projectile flight paths like that of Angry Birds. Angry Birds employs the notion that a previous shot is shown with a dotted line "arch" showing the player where ...
3
votes
1answer
609 views

How to implement server side physics?

I am working on 2-player 2d sidescroller. How should I implement the physics on the server? Use one world for every game or use a big world in which I add every 2 player that start a game? I have ...
1
vote
1answer
563 views

Making Ball Fling in a Curve Direction

I was wondering how to figuring out how to slice a ball (banana kick) by flinging it curve-ways. However, according to the LibGDX's gesture listener, the method for flinging only focuses on a straight ...
2
votes
1answer
295 views

Using Box2D for range detection?

I have two entities. One has a sword, one has a bow and arrow. When the bow entity is 100 units away, he needs to begin attacking. Likewise, when the sword entity is 10 units away, he needs to begin ...
9
votes
3answers
1k views

Are collision detection always O(n^2)?

Are physics engine able to decrease that complexity, for example by grouping objects who are near each other and check for collisions inside this group instead of against all objects ? (for example, ...
0
votes
1answer
222 views

Formula throwing a ball to destination [duplicate]

I am throwing a ball using this: double v, vx, vy, alpha, t2 = 0; if (Keyboard.GetState().IsKeyDown(Keys.Up)) { alpha = MathHelper.ToRadians(60f); v = ...
1
vote
2answers
597 views

Jump without bouncing in physics engine

I am using Ogre3D as my rendering API, and OgreBullet as my physics engine. I have an test entity that when the y part of the velocity is 0 and spacebar is pressed, the velocity changes to, lets say: ...
0
votes
1answer
855 views

Moving a Box2D object in the direction it is facing using applyForce [duplicate]

I'm trying to apply force to a polygon physics object to move it. Whilst I can get it to move upwards easily enough, I'm trying to get it to move in the direction in which it is pointing. Here's my ...
0
votes
3answers
523 views

how can we define dynamic Path of ViewObject(Bitmap) On Canvas

I am Currently working on One 2D Android Game, In this game One ViewObject(Bitmap) is moving Across Screen On Parabola Path Like in this Image, But this Path is Static, the Static path is getting ...
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vote
1answer
129 views

Ring and Pole - Box2d

How I can make a b2Body in box2d so that it could form a ring which does not collide from the center just like a ring. like when we flick the object and there's another body (like pole), the pole can ...
0
votes
2answers
251 views

Physics for space game [duplicate]

I am making a space game where you fly a ship. I am trying to work out the physics for such a game and so far came up with: var thrust; //between 1 & 100 how much the engines are pushing var ...