Relating to the motion of objects through space (in 2 dimensions (x,y)) and time. Including concepts such as acceleration (thrust and gravity), mass, collision response, friction and more.

learn more… | top users | synonyms

0
votes
1answer
20 views

Bouncing projectile off of sprite, the sides work but top and bottom do not

I'm having a problem bouncing a projectile off a sprite, we've been asked to move the projectile using the equations of motions which makes things a little more difficult but as far as I can see what ...
1
vote
1answer
81 views

How do I make circles bounce off each other realistically?

I'm trying to create bouncing balls with realistic physics. At the moment, when the balls hit each other, they bounce back in the same direction they came from. How do I make them more realistic? I ...
1
vote
0answers
11 views

Sizing a Box2D ground object

I am developing a platformer game using SDL2 for graphics and Box2D for physics. I am currently designing my levels and would like to know if it is better to make the static part of each level (ie: ...
1
vote
0answers
13 views

Need help in getting sequential impulse method working

i have made a very very simple physics system based on sequential impulse method - with single contacts only and no angular rotation at all. Contact points are calculated using separating axis ...
2
votes
0answers
42 views

How to prevent bullets from passing right through entities?

(sorry for bad english) I'm making 2D arcade game. I write all of physics stuff myself. The problem involves bullet behaviour. Imagine bullet flying towards some entity. If the bullet's velocity is ...
0
votes
0answers
25 views

LibGDX make an object rotate around something

I need to rotate and object, which should be a circle made up with a ShaderRender, around a specified point. In LibGDX there is a method or something which allow me to do this? If it doesn't exist how ...
0
votes
1answer
20 views

Libgdx bouncy effect in a wall

I have an element inside the screen and I want to set my phone's bounds as a wall where elements are bouncing. I want it to be physically correct. How to do this?
0
votes
1answer
79 views

Good collision resolving mechanism

In my game i have plenty of objects that can collide. Literally, most of them can collide with each other.The problem I'm facing is that i can't come up with some good collision resolving way. How can ...
2
votes
2answers
66 views

How do I calculate rotational impulses in rigid body collisions?

I'm writing a simple 2D physics engine to help me understand the inner workings of physics engines. I'm following Randy Gaul's tutorial which can be found here and It's been extremely useful and ...
0
votes
1answer
41 views

Calculating density of an object

I'm using Box2D for physics in my game, and one of the things it needs to know when creating a shape for a physics body is the shape's density. I had no idea what value I should specify, so I went to ...
0
votes
1answer
65 views

Sprite Kit - keeping character level with the terrain 2d endless runner

I've been trying to figure this out exhaustively for the past few days and still haven't found an answer. I have an endless runner built using swift where the character is fixed and the terrain moves ...
0
votes
0answers
14 views

how to trigger a ball from rotating cube in z axis

how to release ball from the cube which is rotating in z axis, ball should move in Y axis and ball should be reloaded after releasing the ball ?? Thanks in advance cheers Gokul
10
votes
4answers
334 views

How is RTS Local Avoidance Done?

Currently, I'm simulating physics impact forces for local avoidance of units but this method sometimes pushes units out of formation and has very undesirable effects when units clump up. For RTS ...
1
vote
1answer
33 views

b2DistanceJoint with frequency equal to 0 vs b2WeldJoint

What is the difference of b2WeldJoint and b2DistanceJoint? They both have frequency and also when you put frequency of Distance Joint to 0 it acts like Weld Joint. It seams that you can create ...
1
vote
1answer
199 views

Why does my character stop a little before landing on the ground?

I made a little game with side-scrolling and a box (the player) jumping across the level. The simple physics are almost done, but I have two problem with the way things behave: On landing, the box ...
2
votes
1answer
53 views

In Box2D, how do I create an infinitely oscillating spring?

How do I create an ideal spring that can oscillate indefinitely using Box2D? A b2DistanceJoint works almost perfectly, but it eventually slows to a stop, even with damping set to 0. I think it is ...
0
votes
1answer
38 views

Unity 2D Current object force

I'm working on a game with an entity firing a shot. This shot could destroy other entities as well as the entity who generated the shot. My first step was to apply a force to the rigidbody2D of the ...
1
vote
0answers
77 views

Create a 2D orbit trajectory like in angry birds space and a circular orbit

I am working on a 2D game, and I am working on adding some space physics : I need to find a way to create a circular orbit and an orbit like angry birds space ( the spiral trajectory ) . So there is 2 ...
0
votes
0answers
31 views

wheeled 2D character controller platform edges problem

I have built a little wheeled 2D character controller (a rectangle for the body and a circle for the legs with a motor joint). Everything is ok but the problem is that when the player reaches the edge ...
0
votes
3answers
111 views

Moving one object from one point to another with acceleration

How would someone implement moving an object from one point in 2D space to another using these formulae to update objects: m_position.setX/Y( m_position.X/Y() + m_velocity.X/Y() * dt + 0.5 * m_acc * ...
2
votes
2answers
85 views

Why doesn't this 2d physics calculation yield the desired jump height?

I found a formula for gravity and jumping in this article: http://error454.com/2013/10/23/platformer-physics-101-and-the-3-fundamental-equations-of-platformers/ I implemented this formula and ...
0
votes
2answers
43 views

unity2D Top-Dow Mobile rigibody2D

im using this code for my 2D TopDown mobile player movement.but when i move player With UI Image buttons player keep moving.it didnt stop.and also player starting of move he is very slow. the he ...
0
votes
0answers
61 views

Rain World : How to have intelligent movement / animation?

In the project RainWorld the characters seem to move "intelligently" as they move "unrestricted". They seem to know "how" to move their limbs and "what" needs to be done. Here for an example the ...
0
votes
1answer
66 views

Spherical Collision

I have a made spherical collision system which creates a major problem, the balls gets stuck to each other on high speed and sometime with low speed collisions. I researched a lot but I couldn't found ...
0
votes
0answers
15 views

How can I track a leader vehicle at a specific angle and distance?

I am using Matlab and have code which allows a vehicle to find its way to certain coordinates chosen by the user. I now want to add a second vehicle which stays fixed at a specific distance and angle ...
0
votes
0answers
96 views

Physics2D.OverlapCircleAll seems to be bigger than my radius

Im trying to make a "Scorched earth"-like game using unity. I managed to fire my bullet and make it explode on contact. What I am trying to do is do some damage to the tanks even if the bullet didn't ...
0
votes
1answer
66 views

How do I make a time lapse in my code so it updates slower?

I have made some collision if statements, but they didn't work. birdbox3.X += 5; birdbox3.Y -= 5; if (birdbox3.Intersects(Banner1)) { birdbox3.Y ...
0
votes
0answers
51 views

Does unused 2D colliders in Unity affects performance? Is an Edge Collider more performance friendly than BoxCollider2D?

I am using a lot of gameobjects for my platformer that uses BoxCollider2D component to make the scene floor. But only an a selected set of gameobjects actually have some interaction with the player, ...
0
votes
0answers
21 views

Launching projectile from a “canon” [duplicate]

I'm working on "Scorched earth"-like game just for learning purpose. I can't figure out how to launch the projectile from my tank's position, with a power of X ([0,100]),at an angle of Y ([-180,180]). ...
0
votes
1answer
51 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 ...
1
vote
1answer
171 views

Cocos2dx+Chipmunk: Fully elastic collision between moving bodies

I'm using Cocos2dx and the built in Chipmunk physics engine, and currently I've got my PhysicsBodys' materials set up with: Density=0 Restitution=1 Friction=0 in order to get fully elastic ...
1
vote
1answer
102 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
53 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, ...
0
votes
0answers
36 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 ...
-1
votes
1answer
55 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
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
2answers
126 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 ...
1
vote
0answers
57 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 ...
2
votes
2answers
270 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. ...
1
vote
1answer
72 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: ...
0
votes
2answers
168 views

Unity2D Collision Issue

I have a crate setup (in pic below) with a rigid body component, box collider and 3 circle colliders(they allow me to push the crate most of the time without getting stuck on the floor textures which ...
-1
votes
1answer
106 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 ...
0
votes
1answer
47 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 ...
1
vote
3answers
87 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 ...
2
votes
1answer
213 views

How can I manage the deceleration of units so that they arrive on-target?

When I first started trying to set up my air units' movement in my RTS game, I thought it was going to be easy with simple Euler method linear acceleration. This was far from the case as the ship ...
1
vote
3answers
642 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
125 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() ...
1
vote
1answer
230 views

Anchoring HingeJoint2D to clicked upon spot

I'm creating a 2D game where the user can click and drag objects around. This is done by connecting a 'Hand' object to the object the user is current clicking on with a HingeJoint2D. Right now it ...
0
votes
0answers
26 views

How to tell if the ball is on the floor (in nape)?

What I wish to do in pseudo code: points = Get the set of all points (x, y) where the ball is touching other surfaces. point = Get the point out of that set with the minimal (y) value. Check if that ...
1
vote
1answer
44 views

Reduce bounciness of dynamic bodies in Box2D

In my 2D platformer game my player character is modeled using a Box2D dynamic body. One thing I thought feels off though is that even though the restitution of the fixture applied is zero, the player ...