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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2answers
68 views

How do I implement friction in a billiards game?

I'm having trouble implementing friction in a billiards game. Currently, the ball only slows on collision with the edges, but I also want some friction with the background. How can I implement ...
-1
votes
0answers
30 views

How to add degrees of freedom for a spacecraft?

I've concluded that the number of degrees of freedom for a UFO in zero gravity should be 10: W (thrust), A (left), S (drag), D (right), Q (lift), E (weight) but this is not enought degress of freedom ...
-1
votes
0answers
30 views

Collision Detection and Response Woes [closed]

I've been trying to implement the collision detection and response detained in this paper: http://www.peroxide.dk/papers/collision/collision.pdf After pretty much copying the code line for line some ...
11
votes
4answers
3k views

Physics engine recommendation which can simulate pool game correctly? [closed]

I'm making a pool-game like game. This game requires correct (or very accurate) reflective bounces. I tried Box2D and Bullet Physics, but they both have this problem. If there is a wall on top of ...
0
votes
0answers
33 views

Determine speed of sprite

I'm trying to calculate the speed of my sprites in Cocos2d but I'm having some difficulties. I'm not sure which units of time/speed cocos2d uses. My background sprite moves 2 positions to left each ...
0
votes
0answers
50 views

Simple Libgdx bullet example

I'm looking for a SIMPLE example of the use of the bullet physics engine in libgdx. Before you point me at the wiki, I have read that, but that mostly describes installation, and just a "raw" ...
0
votes
0answers
23 views

setChaseEntity freezes or jitters the AnimatedSprite

I'm trying to implement setChaseEntity method in a physics based app. I wrote the below code which has an animated sprite ans as the player. The player is movable and it can jump. When i try to focus ...
0
votes
1answer
68 views

Relative Position/Rotation calculation

I have 2 objects each with a 3x3 Matrix (Orientation) and a Vector3 (Translation). Both are relative to world coordinates. How do I calculate the position and orientation of object B in relation to ...
2
votes
1answer
206 views

Transforms in Box2D

I'm attempting to implement a camera in my game. I had it working 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 ...
0
votes
1answer
53 views

Is there any reasons to make sprites and bodies line up?

So in LibGDX the Sprite objects position is where it's 0,0 mark is in the word. In Box2D a a bodies position is in it's center. So to line these up when you update the sprites position with the ...
1
vote
1answer
64 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 ...
2
votes
1answer
218 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 ...
2
votes
2answers
64 views

Can I make a character solid but not lose non-physics behaviour?

My character can walk around in the world, but walks through other objects, for example a cylinder (stand-in for a cannon). To fix this I added a capsule collider to each of the character and ...
0
votes
1answer
75 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 ...
1
vote
0answers
51 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 ...
0
votes
1answer
118 views

How do I prevent other dynamic bodies from affecting the player's velocity with Box2D?

I'm working on my player object for my game. PhysicsBodyDef def; def.fixedRotation = true; def.density = 1.0f; def.position = Vec2(200.0f, 200.0f); def.isDynamic = true; def.size = ...
1
vote
1answer
3k views

LibGDX Box2D Body and Sprite AND DebugRenderer out of sync

I am having a couple issues with Box2D bodies. I have a GameObject holding a Sprite and Body. I use a ShapeRenderer to draw an outline of the Body's and Sprite's bounding boxes. I also added a ...
0
votes
0answers
42 views

How to find correct offset to adjust sprite to the position of box2D body after rotation

I am trying to implement phsyics with the as3 box2d port. I currently have a b2body for each of some certain sprites in my game and I am able to update the sprite's positions correctly from the ...
0
votes
0answers
34 views

2D Collision in JavaFX - Bad accuracy with .intersects()

I have several Shape objects - Circle, Rectangle and Polygon. I use the built-in .intersects(Bounds1, Bounds2) method to detect collision but it's quite inaccurate. Circle c1 = new Circle(20); ...
2
votes
1answer
129 views

Calculating/Predicting a way

I'm just starting with physics, so I'm not always sure about what I'm doing. It's a 2D project but I'm using 3D physical objects like SphereCollider etc.. What I have: Objects floating in space and ...
0
votes
1answer
73 views

How to make character gain acceleration?

I want to create more realistic physics for my 2D games. Currently, the character and the other game objects in my games start moving instantly (achieve maximum speed instantly) and stop instantly ...
0
votes
1answer
62 views

How can I get a function of time for coordinates of a 2D-moving body in a gravitational field from equations of forces?

I am having a hard time with writing code for simulation of 2D motion of a body with mass in a gravitational field of another body. I have 2 masses and a gravitational force equation. I know that ...
1
vote
1answer
671 views

Basic Car Movement, Converting 2D Vectors to 3D problems

I'm trying to follow this guys method for steering a basic car. Link. It's the first example I can sort of get my head around and I'm trying to convert it to a working 3D version. To get some scope, ...
0
votes
1answer
230 views

Circle vs. Rect Collision accuracy problem

The blue ball is dynamic and is supposed to bounce off the walls, as well as the rectangle. Currently, the green rectangle is adding an invisible line to the scene, which doesn't let my ball go where ...
7
votes
4answers
12k views

2D character controller in unity (trying to get old-school platformers back)

This days I'm trying to create a 2D character controller with unity (using phisics). I'm fairly new to physic engines and it is really hard to get the control feel I'm looking for. I would be really ...
0
votes
0answers
51 views

How to design basic physics and movement behavior for 2D platformer?

I want to make a simple 2D platformer. I know some basic 2D physics and how to implement them in a game. How to make a character jump, accelerate, decelerate, etc. But I have no idea how to actually ...
0
votes
0answers
32 views

Issue with implementing friction for player movement

I have been writing a 2.5D FPS engine in the same style of Doom and Duke Nukem 3D. The game is 3D rendered but the world is represented in 2D. This is my current position update code for an entity ...
1
vote
1answer
41 views

How to apply steering to a physics body correctly when using a physics engine?

I have a top down 2d game that uses a physics engine (Farseer). I'm using the standard steering behaviors to make the AI move around but I'm not sure the correct way to take the so called "steering ...
1
vote
0answers
28 views

How do you calculate the rate of rotation using the accelerometer values in Android for a particular axis?

I am developing a simple game which involves a character moving up and down only along the Y axis. Currently I am using the accelerometer readings to change the Y velocity of the character. The game ...
1
vote
0answers
88 views

Conceptual - What is the optimal way to combine steering behaviors with rigid body physics?

I am working on a simple 3D space simulator that makes use of the Bullet physics engine. The spaceships are rigid bodies that have a mass and hitbox so that they can be considered for collisions. At ...
1
vote
0answers
830 views

Why do restitution values less than one still cause infinite bouncing in Box2D?

I'm currently trying to implement basketball bouncing into my game using Box2d (jBox2d technically), but I'm a bit confused about restitution. While trying to create the ball in the testbed first, ...
0
votes
0answers
16 views

Handling gyroscope data

I'm working on a mobile game that allows user to rotate player around an axis using accelerometer. In addition to that, to allow fast, almost instant, rotation I thought of using gyro data. It seems ...
0
votes
3answers
67 views

How can I calculate force and acceleration?

I have problem of calculating the movement of the object. At the moment, I have a vectors calculated from the center of the screen minus the position of the object. direction vector = centerScreen ...
0
votes
2answers
62 views

Artillery Simulation [duplicate]

I need some help on a simulation of an Artillery like this one https://www.youtube.com/watch?v=YktWSKo_UbA. I cant figure out how to make the "tomato" to get to the selected spot. Where can I get ...
3
votes
1answer
88 views

How do you prevent AABBs from passing through each other?

I know what an AABB is, but I don't know how you would check for collision with an object that is going really fast. If an object goes fast enough, it can skip over other bounding boxes without it ...
17
votes
2answers
738 views

How do I make a character capable of walking on walls?

I am trying to get a character to move like a spider: Given a rising slope which a ball would normally not be able to roll up, the spider would slowly crawl up. Similarly, given a mid-air rectangular ...
4
votes
1answer
154 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 ...
0
votes
1answer
151 views

How do I determine a good path for 2D artillery projectiles?

I'm building a little "tank wars" game (like this one). I understand the math, and I am able to define a parabola from the launcher to the objective I want to reach. The parabola depends on the ...
2
votes
1answer
41 views

What are the parameters for btHingeConstraint::setLimit

What does each parameter in btHingeConstraint::setLimit do to the hinge constraint? void btHingeConstraint::setLimit ( btScalar low, btScalar high, btScalar _softness = ...
1
vote
1answer
82 views

Looking for a peer reviewed article that details the benefits of a physics simulation within interactive media [closed]

I'm hoping this is the correct place to ask this question as it is video game related and can be seen as a key ingredient in modern game development. Does anyone know of a peer reviewed article that ...
0
votes
1answer
154 views

Planet gravity? [duplicate]

I am trying to make a game with the Phaser game engine and would like to implement some sort of planetary gravity. Essentially I just want the player to be able to walk on a circle or orbit a point. I ...
0
votes
2answers
191 views

Best collision shape for rooms

I'm wondering what is the most efficient collision shape to use with APIs like Bullet or Havok for rooms/interiors. Rooms tend to be boxes but are concave since the normals point inward which means no ...
1
vote
0answers
67 views

Spin wheel with gesture in Andengine

I want to implement Fortune wheel in Andengine. The wheel would start spinning based on the speed of a finger fling. Then it would stop slowly like real Fortune wheel. What I am able to do now is to ...
0
votes
0answers
83 views

Polygon Collision Response

I'm working on a game engine that has a built in custom physics engine (I know it's a waste of time, but I have years to make this, so why not make it good?). Currently, with any number of polygons, ...
6
votes
1answer
388 views

Weird problem with advect program in fluid simulator

I implemented 2d fluid simulator. Solver runs entirely on GPU. All works fine... on my work PC. But on home PC I have some awful glitches, and I can`t understand how to fix them. Empirically I ...
2
votes
1answer
174 views

3D-Physics of a Rubber Ball (Squash)

I'm trying to simulate the environment on a Squash Court on Android with my own physics and using OpenGL for visualization. Basically, its about a rubber ball bouncing around in 3d, not just on the ...
14
votes
2answers
3k views

Why is RK4 better than Euler integration?

At the end of these great slides, the author compares all the different integrators presented. One way or another, they all fall short except for Improved Euler Integration and Runge Kutta 4 ...
0
votes
1answer
185 views

How do I implement swipe-to-throw in Andengine?

I have a ball sprite and I apply physics to it when the user swipes on it. I'd like the ball to start moving in the direction of the swipe, similarly to how Paper Toss works. How can I do this?
1
vote
1answer
132 views

Ice sliding physics

I am trying to implement ice sliding physics on a plane for my game. There are a lot of N64 games that implemented them perfectly well, like Banjo-Kazooie, Super Mario 64, Zelda: OoT and MM, etc. ...
0
votes
1answer
58 views

Bullet3: Issue with applying force once an object is at rest

I just started using bullet and I'm having an issue where once my rigid body is at reset at the floor it won't move when I apply a force to it. I have created a small demo to show this using the ...