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
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 ...
0
votes
1answer
42 views

Making a gameObject push the player

I am working on a Unity 3D game for Oculus and I have problems with making my objects to apply physics on a player. So getting rid of a CharacterController and using something like a rag doll is not ...
1
vote
1answer
41 views

Gravity Simulation failing at short distances

I have a 2D space simulation with gravity acting on three bodies (e.g. sun and 2x planets). The simulation seems pretty stable with RK4 (was unstable with Euler). The problem arises if the orbit of ...
2
votes
3answers
150 views

Formula for Planetary Alignment

I am attempting to create a game where there is a universe of two 16-bit addresses ranging from -32768, -32768 to 32767,32767, or in hexadecimal, each value can run from $8000 to $FFFF then 0 to ...
3
votes
1answer
81 views

2D Physics: What happens with torque when center of mass changes?

Novice programmer and explorer of simple 2D physics, here. I have a simple 2D object made up of two rigid bodies connected at a fixed joint. The two rigid objects can rotate freely about that fixed ...
0
votes
2answers
72 views

Why does this simple if-statement that checks my main characters state never get called (Java/LibGDX)?

Been working on this for a while - basically I want my player to perform a front flip when he jumps (screen tap -> player jumps). I wrote the animation class Animator (extends Player implements ...
1
vote
1answer
531 views

Spritekit - gradually apply force vector in different direction (space ship turning)

I have a space ship that I'm applying a force vector to using a joystick for control. I would like this to smoothly fly around when I'm switching directions.. Exactly like minisquadron if you've ...
1
vote
1answer
247 views

Bullet 3D Physics Objects Not Rotating?

So I've got Bullet 3D controlling the motion of objects rendered with DirectX. In the clipping below I've got 2 identical rectangles & 5 balls. The lowest rectangle has a mass of 0 and doesn't ...
0
votes
1answer
37 views

Rotate a plane defined by its normal and its distance

First apologies for the amount of pictures, it's a bit hard trying to explain my problem without pictures. Hope I've provided all the relevant code. If you feel you want to know about how I am doing ...
2
votes
0answers
237 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
55 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
900 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
65 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
92 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
271 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
88 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
151 views

LibGDX Bounding Rectangles

I'm creating some rectangles surrounding my sprites for my player and bullet class to detect collisions with the overlaps method in Intersector class of LibGDX. I have a question: When I instantiate ...
0
votes
0answers
42 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
38 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
30 views

LibGDX - Executing 2 different touchDown events in the same method

On the bottom left of my screen is a circle with an Arrow and on the bottom right is a circle with a gun. If the player is in jetpack mode and the Arrow "button" is clicked he flies like flappy bird ...
0
votes
1answer
44 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
1answer
30 views

Getting distance between point of an object and another object in Unity

First, I'd like to apologize because this is a very basic and repetitive question, but I am completely new to game development. I understand that I can find a distance between two objects using: ...
0
votes
2answers
92 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
181 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
611 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
98 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
83 views

Custom arcade physics rate (e.g. bullet time)?

Is there a way to modify the rate that physics is applied, either globally or on a per-sprite basis in Phaser? That is, how can I slow down or speed up the rate at which sprites move around, or fall ...
0
votes
1answer
52 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
70 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
38 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 ...
0
votes
1answer
66 views

Moving CCNode with constant speed in cocos2d

I want to move the object (CCNODE) with constant speed in any direction , what i have did till now is applied a force to object at start to get it moving and set elasticity as 1 and friction as 0 to ...
0
votes
2answers
318 views

3D collision physics. Response when hitting wall, floor or roof

I am having problem with the most basic physic response when the player collide with static wall, floor or roof. I have a simple 3D maze, true means solid while false means air: bool ...
0
votes
1answer
36 views

Immovable object impact physics

I am trying to do some physics calculations from scratch, and as a result am creating a small bouncing ball example. However, I have some issues getting correct results from my impact physics when the ...
0
votes
1answer
22 views

Box2D: Making it Determinsitic?

From articles on the web, I found that floating point math generally has accuracy of at least 6 digits. With this in mind, is it possible to make Box2D which uses floats fully deterministic through ...
1
vote
3answers
2k views

Collider2D and Rigidbody2D, how do they work?

I have been learning JavaScript and Unity for a week now. I learned how to make Cube as a Ground and another Cube as a player and I used this code to make the Player Cube move forward and backward and ...
0
votes
1answer
49 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
37 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
1answer
201 views

Grid collision - finding the location of an entity in each box

I am trying to implement grid-based collision in a 2d game with moving circles. The canvas is 400x400 pixels. Below you can see the code for my Grid class. What I want it to do is check inside which ...
0
votes
4answers
346 views

What is the easiest way to make an object follow the edge of a sprite?

I have a rounded rectangle sprite and another sprite that's just a circle. I want the center of the circle to follow the edge of the rounded rectangle. Is there any easy way to accomplish this task? ...
0
votes
0answers
32 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
43 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 ...
0
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0answers
16 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
117 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
40 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
72 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 ...
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
47 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 ...
3
votes
3answers
129 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, ...
3
votes
2answers
683 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.