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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2
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0answers
253 views

Inverse Dynamics How to [closed]

I have some motion capture data (kinect) that records all body joints (32fps) and I want to take particular positions (for example when a person moves both of his hands up in the sky in celebration ...
2
votes
1answer
64 views

How to restrict jumping to a single jump?

I'm making a VolleyBall game in HTML5 with PandaJs GameEngine and plugin is used physics and Box2D. The problem is that players can jump, but they can jump over the net with multiple jumps. I have ...
3
votes
3answers
1k views

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 ...
0
votes
0answers
209 views

Anti-Roll bar doesn't work

I'm making a racing game in Unity that has trucks as vehicles. For the truck movement, I'm using WheelColliders. After some testing, I found out that after a certain speed (~60km/h), turning made the ...
2
votes
1answer
178 views

Frame independent buoyancy using Substepping

I am having trouble with a frame independent buoyancy force using substepping in Unreal Engine 4. The original problem (which I am attempting to solve using substepping) is that when you apply a ...
4
votes
2answers
309 views

Jelly ground collision

For fun I am trying to replicate the mechanics from The Floor is Jelly. So far I have successfully created "jelly islands/blocks" which are represented by an array of points and then drawn by using ...
2
votes
1answer
159 views

Unintended sliding blocks Unity (5) physics

A game I'm working on right now relies on the Unity physics system for collisions, gravity etc. This all works well except for one strange thing. When an explosive is placed on a stone cube, it'll ...
0
votes
1answer
77 views

Using Box2D for soccer physics

I've learned quite a bit of Box2D and I've succeeded basic stuff concluding ball physics. I want to implement 'opposing forces', as the character kicks the ball with a certain strength, with the leg ...
0
votes
0answers
87 views

How can I handle ball interaction with lanes in a pinball game?

In a pinball game, how can I handle collision or constraints on the ball for convincing movement on those highway rails/tracks? I assume using physics and a mesh collider would not work, even when ...
0
votes
1answer
54 views

Dragging an object and moving it back to it's original position on release?

I'm making a small game, and I'm trying to add this mechanic where if you click on an object and move it, then you release the object it will snap back to it's original position. Currently, each ...
0
votes
1answer
98 views

How to reference the right object in Unity

So, I'm developing this small 2D project where I have a sphere that detects if objects get close to it from three different directions. I have successfully found a way to detect if an object ...
0
votes
2answers
284 views

Realistically drivable car

I want my car to be realistically drivable (like in real life...) Unfortunately all I did so far is Rotate the whole vehicle using A and D; and AddForce in forward-backward direction using W and S ...
1
vote
3answers
419 views

How to implement accurate frame-rate-independent physics?

So, I have been working on a project for a while now and recently stumbled across a problem: The common approach to frame-rate independent physics is to either use a fixed update interval (ie. Unity) ...
4
votes
3answers
693 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 ...
2
votes
1answer
203 views

2D bouncing ball simulation - angular velocity

How does angular velocity of a ball affects it's speed after a bounce? I'm trying to simulate 2D bouncing ball physics. I've found a nice solution how to calculate ball's velocity after a bounce: ...
0
votes
1answer
90 views

How do I get realistic sliding contact between objects in a voxel grid?

I have a 3D grid of voxels in my game. Entities walk around with simple physics that represents them as an axis aligned bounding box with velocity, mass and acceleration. The way I'm doing collision ...
1
vote
1answer
99 views

What is the purpose of integration in physics engines?

All online resources seem to assume that you know what this means and/or state that this is related to object movement in some way. How does this differ than just position.x++ and position.y++ and ...
0
votes
1answer
55 views

How to move a car model on a plane?

I want to create a 3 dimensional car game. But i have a problem in moving a car in other directions and accelerating. I have a car model and a road model placed appropriately. To move car forward, I ...
1
vote
1answer
219 views

Dynamic body in Box2D with fixed position

I need to fix the dynamic body position so that it would not rotate and would not move even if there are other forces, collisions and so on. Let me first explain why I need this. I have a dynamic ...
0
votes
1answer
57 views

Physics-based rotation with an array of pixels

Say I have a simple system, that has a large array of pixels with their own weight, velocity, coordinates etc. (by using classes) if each of those pixels can be connected to 4 other pixels (top, ...
1
vote
1answer
56 views

Finding the side of a shape a ray intersects

For some simple 3D shapes (cubes, prisms) how can I determine which side a ray intersects, knowing the direction of the ray, and the normals of the shapes' sides. I thought of using plane ...
0
votes
0answers
57 views

PhysicsJS object falls through the world

I have a problem while using PhysicsJS when it comes to collisions. I created a physics world, an object and applied gravity. I put the object at a certain position, it falls down because of the ...
0
votes
0answers
117 views

moving a character in sprite kit

So I've created a game in which a number of tiles are created from a txt file to create a level for the player to navigate through, but I'm having trouble moving the player. func ...
-1
votes
1answer
83 views

Relative movement in Box2D (keep object from falling off planet)

I'm creating a game with planets orbiting around a sun, like this: The brown square is the earth, rotating around its center and around the sun. The yellow square is the sun, which doesn't move. Now ...
1
vote
0answers
19 views

Java JBullet models not colliding [duplicate]

Hello I wan't to do model collsion in JBullet but that don't won't to work. Models look like have some invisble holes. Here the code for creating collsion shape: int triangles_count = (int) ...
-1
votes
2answers
145 views

Does conservation of energy exist in most physics engines?

The reason I am wondering, is because while trying to create gravity around a point in the physics game I am creating, I wondered "If I create an object in the middle of the screen, where would the ...
0
votes
0answers
49 views

Stuck on a steering problem

i'm building a car game, and currently working on the steering. i would like to change the motion of Z rotation so that the car rotates around the Z axis when the wheels are turned. I can't set the ...
0
votes
2answers
215 views

How do I derive an appropriate acceleration value for my game?

I am creating a Flappy Bird clone from this tutorial. I have a question about acceleration in libgdx. The author assigned the bird a constant acceleration vector in the constructor of the bird ...
2
votes
2answers
413 views

2D Boat controlling physics

I'm working on a top-down 2D boat game with Unity3D. I couldn't able to understand how to implement physics of rudder controlling. My physics knowledge is not enough to think how rudder dynamics work. ...
0
votes
1answer
275 views

Explain the difference between extrapolation and interpolation

http://www.unagames.com/blog/daniele/2010/06/fixed-time-step-implementation-box2d here there are two algorithms of smoothing in case of fixed time step physics simulation. I don't understand the ...
0
votes
0answers
13 views

How to experiment for the value of gravity in Libgdx? [duplicate]

I am following a guide on how to play a flappy bird clone in the LibGdx framework. -http://www.kilobolt.com/day-5-the-flight-of-the-dead---adding-the-bird.html I am currently on the part where the ...
0
votes
3answers
89 views

[Unity]Avoid boucing when ground move down

I have a sphere & a quad, when the quad move down, the sphere fall after and bounce back continuously. I dont want to change my project setting like bounciness, gravity,mass and I need the sphere ...
1
vote
0answers
74 views

Farseer: Friend/Foe Collision - cannot push foes but friends

we are using Farseer in our project and I try to find a setup to achieve the following quite complicated collision behavior: Friendly Units can push each other aside. However, the push should be a ...
3
votes
3answers
177 views

Sound Synthesis from object collision in Virtual Reality Environment

I have a project whose subject is "Sound Synthesis from object collision in Virtual Reality Environment" First of all, I have to define some objects with certain attributes (like shape, mass, ...
1
vote
1answer
73 views

Lots of bouncing balls sink into each other [closed]

I'm trying to model a system that simulates an arbitrary number of bouncing balls with some gravity. So far I've come up with a solution that can be seen here: ...
3
votes
2answers
789 views

Calculating torque required to turn an object to a target rotation, depending on timestep

The function below works fine, when the timesteps of the physicsengine are short enough for the function to update often. It determinates when the ship(the object) needs to start decelerating to reach ...
19
votes
4answers
7k views

Is there a 2d physics engine that can model fluids and gases? [closed]

At this point the platform and programming language don't matter I would just like to know if something out there exists for this. Any help is appreciated.
0
votes
1answer
67 views

Using box2d with starling

In my game I have a Main class in which i am initializing starling framework by passing Game class like below myStraling = new Starling(Game , stage); In the game class I have Instances of Welcome ...
66
votes
5answers
31k 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
votes
1answer
146 views

2D bouncing formula doesn't work properly

am new to unity, and i am trying to create a bouncing ball, so i've did many researches about bouncing realted physics and i found a formula : Formula: -2*(V dot N)*N + V Where V is the velocity ...
9
votes
4answers
1k views

How do I implement deceleration?

I say "deceleration" because I'm not using acceleration at the moment; what I mean is moving the velocity back towards zero, eventually stopping. I'm new to vectors and not so great with physics and ...
0
votes
1answer
54 views

How to reposition a bouncing ball after it has passed through a surface

I have a bouncing ball which can collide with lines of a random slope. The ball passes through the lines a bit and I need to set the ball back some distance from the line. The ball (defined by ...
0
votes
2answers
8k views

Why would Rigidbody.AddForce not resulting in movement of my objects?

I'm trying to get my card objects to spread out randomly but nothing happens. I know the method is called cause I get the prints in the console for each card. But they don't move. No errors reported. ...
1
vote
3answers
98 views

Unity2D: Apply gravity to some items, when everything else is gravity-free?

Sorry for the incredibly vague title: Let's say you have an NPC, and when he dies he'll spawn items, coins for example. Instead of just pushing the coins in random directions it would look a lot ...
5
votes
1answer
405 views

Programming Dynamic 3D Water/Waves?

I'm a little bit stuck on how I might go about programming dynamic, interesting water in a game. To qualify that a little bit, I'm interested in creating water with broad, rolling waves that affect ...
1
vote
3answers
885 views

Unity rigidbody2d.velocity jumping causes weird bouncing

Im working on a game 2d game that has some platforming. I followed this video as guidance and produced the following code: public class PlayerControler : MonoBehaviour public float ...
0
votes
0answers
63 views

Calculate hit-normal from collision

I am trying to implement a swept test collision between an AABB and a Line Segment and I found this implementation working great ... Except that it doesn't cover how to calculate the hitNormal and ...
0
votes
2answers
2k views

Unity Physics Material - Character Slides Too Much

I am currently working on a 2D platformer in Unity. I am using a prefab from the AssetStore for my character (The last paragraph contains a link to the prefab). The character has a circle collider for ...
0
votes
0answers
211 views

SpriteKit: Is applyImpulse not working correctly?

I am writing a free throwing system and because of this, I created a ball using following code. self.ball.position = CGPointMake(posX, posY) self.ball.fillColor = SKColor.blueColor() ...
2
votes
3answers
166 views

How to make an object oscillate left and right?

I can't seem to make an object move left and right, back and forth, on room start whilst on solid ground. Codes I used: Step Event: if image_index is greater than 5, then physics_apply_force ...