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

1
vote
1answer
174 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 ...
2
votes
1answer
56 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 ...
1
vote
1answer
16 views

How to move sprite mimicking mouse/touch position on some part of the screen?

I am having a difficulty and I am been doing it wrong, I think. I want to move sprite relatively to touch. Just like when you are playing space shooter like 1943. I just learning some math and try to ...
1
vote
1answer
748 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 ...
0
votes
2answers
122 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 * ...
0
votes
1answer
175 views

Mobile: Physics and movement actions

I've been using spritekit for a while for a few small games. One thing I've noticed is that spritekit is the first game framework I've used that allows me to apply move actions to physics bodies. ...
0
votes
1answer
21 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 ...
0
votes
1answer
313 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 ...
1
vote
1answer
83 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: ...
0
votes
1answer
1k views

Slope polygon collider 2D causing box collider 2D to 'bump' while sliding on it

I'm doing procedural terrain generation. So far I've created the mesh, and attached a 2D polygon collider to it. The terrain is made up of hills going up and down. After doing so, I put a 2D rigid ...
1
vote
0answers
14 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 ...
0
votes
1answer
478 views

Swinging a sword in Xcode with Sprite Kit

I'm working on making an RPG in Xcode, and I'm having a major gameplay issue when it comes to having my character swing his sword in a way that is realistic and gameplay compatible. Right now, when ...
2
votes
1answer
202 views

How to impale and stack targets correctly according to the collider and its coordinate?

I'm making another simple game, a catch game, where a spawning target game object must be captured using a skewer to impale it. Here how: At the start, the falling object (in red) will fall in a ...
2
votes
2answers
248 views

Sprite Kit - containsPoint for SKPhysicsBody?

I have a ball bouncing around the screen. I can pick it up and drag it onto a "bucket". When my touches finish, I use the containsPoint function to check and see if I have dropped the ball onto the ...
2
votes
2answers
303 views

Collision detection via adjacent tiles - sprite too big

I have managed to create a collision detection system for my tile-based jump'n'run game (written in C++/SFML), where I check on each update what values the surrounding tiles of the player contain and ...
0
votes
2answers
553 views

Use both AddForceAtPoint and change velocity property?

I'm using Rigidbody2D for some game objects. It seems that when I AddForce() or AddForceAtPoint(), the game objects are mostly affected on the Y axis and hardly at all on the x axis. I don't ...
0
votes
0answers
26 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 ...
7
votes
4answers
1k views

Determing an object's position along a curve over time

I have some objects in my game which are "thrown". At the moment I am trying to implement this by having these objects follow a parabolic curve. I know the start point, the end point, the vertex and ...
0
votes
2answers
143 views

very simple math destination and speed calculation

My player goes to (destinationX, destinationY) His position is: (x,y) and the player has an update event function update() { this.x = this.x + dx; this.y = this.y + dy; } what is the formula ...
26
votes
2answers
1k views

Calculating the rotational force of a 2D sprite

I am wondering if someone has an elegant way of calculating the following scenario. I have an object of (n) number of squares, random shapes, but we will pretend they are all rectangles. We are ...
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
80 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 ...
0
votes
1answer
69 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 ...
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
42 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 ...
5
votes
2answers
161 views

Determining a sensible gear-like hierarchy for a series of connected objects

I would like a series of objects to behave in similar manner to a series of connected gears. This means that each black object in the diagram below will rotate at a speed based on the ratio of their ...
2
votes
3answers
162 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 ...
10
votes
4answers
340 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
34 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 ...
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 ...
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
2
votes
1answer
57 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 ...
1
vote
1answer
202 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 ...
0
votes
1answer
40 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 ...
5
votes
1answer
257 views

Physics/Logic behind self-bounce

What would a ball look like when it makes itself bounce. Say, for example that the ball had its own "inner power", was made out of (mostly) rubber, and pulled the top of itself inward and then ...
1
vote
0answers
82 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
2answers
284 views

Cocos2dx - Physics - Abort() When Changing Dynamic PhysicBody to Static?

I just learned cocos2dx v3.3 integrated chipmunk physics engine. Here ,as you see, I create a simple circle with physic as: auto sprite = Sprite::create("circle.png"); auto body = ...
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 ...
8
votes
3answers
2k views

2D soft-body physics engines?

Hi so i've recently learned the SFML graphics library and would like to use or make a non-rigid body 2D physics system to use with it. I have three questions: The definition of rigid body in Box2d is ...
4
votes
3answers
4k views

How can I make my main character move in a parabolic arc when jumping?

I'm entering Android game development, and I already have a computer version of a game I want to publish. The thing is, I want to make this as good as it can be. With that said, I need a physics ...
0
votes
1answer
181 views

2D animated sprite jumping and gravity physics [duplicate]

I'm currently writing a Megaman clone for my school project. So far all I did was making the character run and stay put when needed. Know I want to be able to make him jump using the 'X' button. I ...
2
votes
2answers
87 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
65 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
2answers
171 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 ...
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
97 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
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
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 ...