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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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 ...
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1answer
2k views

New Vector Calculation for Elastic Collision of Circle and Fixed Rectangle

I am writing a fairly simple breakout-style game for Android phones. I have successfully detected the collisions between the ball(s) and bricks. The problem that I am having is in calculating the new ...
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2answers
469 views

Modular spaceship control

I am developing a physics based game with spaceships. A spaceship is constructed from circles connected by joints. Some of the circles have engines attached. Engines can rotate around the center ...
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2answers
298 views

How to implement homing missiles with loops while in transit?

I have implemented missiles that steer towards a target, however this feels kind of boring. I want to add loops! Loops are cool! To do this I thought I could use catmull-rom splines, but that seems ...
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4answers
714 views

Point of contact of 2 OBBs?

I'm working on the physics for my GTA2-like game so I can learn more about game physics. The collision detection and resolution are working great. I'm now just unsure how to compute the point of ...
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3answers
1k views

Interpolate and collisions

Lets take the simple example of a ball bouncing off a wall. The physics is separated from the display. The physics is set to run at say 20 frames per second and the display is running faster than this ...
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3answers
681 views

IndexOutOfRangeException on World.Step after enabling/disabling a Farseer physics body?

Earlier, I posted a question asking how to swap fixtures on the fly in a 2D side-scroller using Farseer Physics Engine. The ultimate goal being that the player's physical body changes when the player ...
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2answers
933 views

Simulating the effects of wind

I am developing a mobile game for Android. It is a 3D jumping game (like ski jump) where wind plays a important role so i need to simulate it. How could I achieve this? The game uses libgdx for ...
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1answer
1k views

How to make a 2D Soft-body physics engine?

The definition of rigid body in Box2d is A chunk of matter that is so strong that the distance between any two bits of matter on the chunk is completely constant. And this is exactly what ...
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2answers
775 views

Development platform for 2D web and mobile games

Is there a game development platform -- similar to Torque, or Unity -- which can be used to deploy 2D games on the following platforms: Web iOs Android Xbox Live Arcade (Preferred but not required) ...
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1answer
236 views

How can I test if an object will “fit” during pathfinding?

I'm tinkering around with a 2d game where obstacles are polygons of arbitrary shapes, sizes and locations, and movable entities (players/enemies) can also be of arbitrary sizes. What's a good general ...
4
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1answer
290 views

Why do my velocity estimates have such a large margin of error

I am writing a script in unity that applies a force to the object to advance it a set distance in an environment without friction or drag, producing a cosine force curve. However, as the target ...
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3answers
974 views

Calculating buoyancy force

I am trying to simulate a buoyancy force for objects submerged/suspended in a fluid in a 2D environment. According to Game Physics: Engine Development: How to Build a Robust Commercial-Grade Physics ...
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1answer
2k views

Non axis aligned bounding box collision and physics

Exactly how much more expensive, and while we're at it, difficult, is it to have non-axis aligned bounding boxes in your framework? I realise that it very much depends on what you're trying to do, so ...
4
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1answer
758 views

Heightmap Physics Optimization/Improvement

I'm working on implementing the physics surrounding a player walking on a heightmap. A heightmap is a grid of points which are evenly spaced on the x and z axes, with varying heights. The physical ...
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1answer
2k views

Farseer and 2D Action sidescroller game

I'm thinking about using Farseer inside my game (I'm not good in physics), which isn't a bad idea. However something happened while I was thinking about that, I found this tutorial: ...
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1answer
417 views

Taking Physics into account for AI Planning

What I've seen in most Game Engines and game engine design is that the Physics Engine is the be all end all system. Basically, AI for example may want to travel to some position, but it simply ...
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1answer
356 views

How to take into consideration the effect of initial rotation of a ball hitting & reflecting off a surface

Hey all, I am trying to take into consideration the effect of inertia of the initial rotation of a ball, hitting a surface, into the exit velocity vector of the ball. My current theory is this: ...
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2answers
269 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 ...
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1answer
190 views

How to manage sleep/awake state of physics body

I have a loop, which updates all the physics, inside the loop I'm updating the position of the objects, first thing is the gravity, which pulls all the objects to the bottom. Now my question is, how ...
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1answer
286 views

Networked Physics - Interpolation Causes Physics Engine to Explode

A major issue I am encountering right now is that my physics engine (BEPU) and my network interpolation are conflicting with each other. The player is a physics object, and so the physics engine ...
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1answer
2k views

making a box2d body move along a Bezier curve/ arc path

I have been trying to make a box2d body move along a Bezier curve/ arc path. Most of the posts I've seen recommend an approach of manipulating SetLinearVelocity and SetTransform to arrive at an ...
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1answer
361 views

BEPUphysics collision with generated terrain?

I've got randomly generated terrain which is stored in a indices and vertex buffer. How do I go about using this for collision in BEPU? It seems I can do it with a Mesh but it would be a waste to ...
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1answer
609 views

Multiplayer box2d networking for turn based game

I am currently in the planning stages for a 2D game for mobile devices which I will be making in C++ using cocos2d-x. The game will be turn based and each turn will have a phase in which the physics ...
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2answers
324 views

Box-box contact information

I have two colliding boxes, How i can calculate contact information like (contact normal, contact point and penetration) . Is there any simple algorithm . Note: i'm using XNA .
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1answer
777 views

RK4 Bouncing a Ball

I am trying to wrap my head around RK4. I decided to do the most basic 'ball with gravity that bounces' simulation. I have implemented the following integrator given Glenn Fiedler's tutorial: /// ...
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1answer
596 views

Tried and true basic movement physics (jumping, not walking through stuff)?

If I sat down long enough, I'm sure I could make this happen, but I don't want to reinvent the wheel if I don't have to, especially if XNA has patterns in place for doing this. For now, I'm working ...
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1answer
243 views

Box2D stable range and position

Box2D marks stable range of object size is 0.1M ~ 10M. This specifies object size range. How about space size? If I make an 1M object at (1000.0f,1000.0f) position? Is it can be stable? Or should I ...
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2answers
423 views

How to detect and collide two elastic line segments?

There are 4 moving physical nodes in 3D space. They are paired with two elastic line segments / strings (1 <-> 2; 3 <-> 4). Part I: How to detect the collision of two segments? Part II: On the ...
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1answer
809 views

Problem with box2d at beggining

I have problem with simple box2d physics: I have two bodies : 1 - static box , 2 - dynamic box. I only want to this dynamic box fall on this static, and lay. But now it looks like that at end , ...
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4answers
611 views

Math and physics, where to start? [closed]

the only math I know how is to add the velocity to position. Thats it. i would like to know how to do more stuff, physics, collision detection with stuff other than perfect circles, etc. But where ...
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2answers
375 views

How to account for speed of the vehicle when shooting shells from it?

I'm developing a simple 3D ship game using libgdx and bullet. When a user taps the mouse I create a new shell object and send it in the direction of the mouse click. However, if the user has tapped ...
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2answers
225 views

Platformer gravity where gravity is greater than tile size

I am making a simple grid-tile-based platformer with basic physics. I have 16px tiles, and after playing with gravity it seems that to get a nice quick Mario-like jump feel, the player ends up moving ...
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2answers
2k views

Easiest Way To Implement “Slow Motion” and variable game speed in XNA?

I have an XNA 4.0 game that I want to be able to switch into slow motion and back again to full speed every now and then. So if you kill an enemy the game switches into slow motion as they explode ...
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1answer
294 views

Change unity physics engine speed

Is there a simple way to change the speed* of unity's physics engine like in the game SuperHot? Any script language is ok but javascript is preferred. *I am not sure if speed is the correct term.
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2answers
189 views

Creating shattering effects without having to use actual physics?

For certain effects like glass shattering and falling objects cracking to reveal their inner contents, are there any tricks or ways to implement these fracture physics without having to use actual ...
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1answer
1k views

Platformer Starter Kit - Collision Issues

I'm having trouble with my game that is based off the XNA Platformer starter kit. My game uses smaller tiles (16x16) then the original (32x40) which I'm thinking may be having an effect on collision ...
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1answer
500 views

Maximum range of projectile fired at given force and elevation

I've gone over this again and again, and my result is obviously wrong when viewed in-action. Here's the initial formula I converted (first one): http://en.wikipedia.org/wiki/Range_of_a_projectile ...
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3answers
1k views

Optimizing Bullet and ODE Physics on consoles and mobile phones

I'd like to use either Bullet or ODE on low powered devices (mobile and consoles), but the frame rates are below the acceptable 25-30fps for simulations. I've found that one articulated body by ...
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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, ...
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1answer
129 views

What is a collision shape?

I am a business developer who is new to game programming. In learning Stencyl, I see that there are things called collision shapes associated with tiles. This seems to be a standard term in game ...
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1answer
404 views

Fluid Particle Grid

So recently I have been looking at some fluid simulation techniques, specifically Smoothed Particle Hydrodynamics. One of the key components is a grid to avoid O(n^2) searches. I have been having some ...
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3answers
895 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 ...
3
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1answer
784 views

Angular Velocity

Hey, I have a particle that is hit with a force F at a particular position on the ball P. How can I calculate the angular velocity of the X,Y and Z axis? The actual rotating of the object should be ...
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3answers
333 views

Adding 'swerve' to a direction

I'm not much of a maths expert, so this is probably quite straight forward. I was playing a soccer flash game where you take free kicks. You provide Power, Swerve and Direction. I'm reading up on ...
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1answer
157 views

Unity's default integration method

Which method(s) does Unity provide for physical integration? RK4? Verlet? Euler?
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3answers
358 views

Throwing a ball and estimating its path using a Physics engine

The problem: A player entity wishes to throw a ball from a known position with a known initial velocity. The surrounding environment contains physical objects that can alter the trajectory of the ...
3
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1answer
137 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 ...
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1answer
5k views

Creating sideways friction in a 2D top down racer

I've been playing around with trying to create some kind of top down racer but I'm having trouble getting the car to turn properly. At the moment this is the code I have to update the position of the ...
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5answers
338 views

Forcing one projectile to follow close behind an initial projectile

I'm shooting out a projectile and I want another projectile to closely follow it. I can't simply shoot out the second projectile at a slightly lesser time because the first projectile may change ...