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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7
votes
2answers
451 views

How does braking assist of car racing games work?

There are a lot of PC car racing games around which have this unique driving assist which helps brake your car so that you can safely turn it. While in some games it just an 'assist', it will just ...
7
votes
1answer
230 views

Determining whether two fast moving objects should be submitted for a collision check

I have a basic 2D physics engine running. It's pretty much a particle engine, just uses basic shapes like AABBs and circles, so no rotation is possible. I have CCD implemented that can give accurate ...
2
votes
1answer
738 views

Apply force to a specific point on a rigid body

In unity I have a rigid body object and would like to apply force to a specific point. For example say I had a cube, I want to hit just the top right corner so it spins as a result. One idea I had ...
6
votes
2answers
834 views

“Super meatboy”-ish replay

I'm making a platformer built from mini-levels - and I want to create a sort of a replay of all the player tries that the player did for the level. My question is - what is the best way to record the ...
6
votes
2answers
4k views

Get collision details from Rectangle.Intersects()

I have a Breakout game in which, at some point, I detect the collision between the ball and the paddle with something like this: // Ball class rectangle.Intersects(paddle.Rectangle); Is there any ...
7
votes
1answer
279 views

How do engines avoid “Phase Lock” (multiple objects in same location) in a Physics Engine?

Let me explain Phase Lock first: When two objects of non zero mass occupy the same space but have zero energy (no velocity). Do they bump forever with zero velocity resolution vectors or do they ...
9
votes
3answers
716 views

Impulsioned jumping

There's one thing that has been puzzling me, and that is how to implement a 'faux-impulsed' jump in a platformer. If you don't know what I'm talking about, then think of the jumps of Mario, Kirby, and ...
5
votes
1answer
622 views

Calculate gears rotation for a realtime simulation

Hi I'm trying to do a game with real time simulations of gears. There is a big Gear with inside a smaller gear. I managed to draw gears with different diameters but equal size teeth, but if i try to ...
-1
votes
1answer
242 views

forward motion car physics - gradual slow

Im having trouble creating realistic car movements in xna 4. Right now i have a car going forward and hitting a terminal velocity which is fine but when i release the up key i need to the car to slow ...
0
votes
1answer
210 views

SFX Played Once per Collision or Hit

I have a question about using Box2D (engine for LibGDX used to make realistic physics). I observed on the code that I've made for the physics here below: @Override public boolean touchUp(int screenX, ...
6
votes
1answer
261 views

How can I derive force vectors from velocity vectors?

I'm making a 2d shooter ala Geometry Wars. I've got my own simple physics at work driving the background grid and all my entities. To move anything in the world I apply a Vector2d force to it. The ...
1
vote
1answer
249 views

Numerical stability in continuous physics simulation [closed]

Pretty much all of the game development I have been involved with runs afoul of simulating a physical world in discrete time steps. This is of course very simple, but hardly elegant (not to mention ...
4
votes
1answer
261 views

How display path ball will bounce?

I'm trying to figure out a way to show the path a ball will travel, so that the player can line up a shot before they fire the ball. I can't think of a way to calculate this path in advance and ...
3
votes
2answers
377 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 ...
46
votes
3answers
11k views

2D water with dynamic waves

New Super Mario Bros has really cool 2D water that I'd like to learn how to create. Here's a video showing it. When something hits the water, it creates a wave. There are also constant "background" ...
-2
votes
1answer
231 views

Move projectile in direction the gun is facing [duplicate]

Possible Duplicate: Move sprite in the direction it is facing? I am attempting to have a projectile follow the direction a gun is facing. When using the following code I am unable to make ...
2
votes
5answers
2k views

How to Make Objects Fall Faster in a Physics Simulation

I used the collision physics (i.e. Box2d, Physics Body Editor) and implemented onto the java code. I'm trying to make the fall speed higher according to the examples: It falls slower if light object ...
3
votes
4answers
3k views

How to move a sprite automatically using a physicsHandler in Andengine?

I use a DigitalOnScreenControl (knob with a four-directional arrow control) to move the entity and the entity which is bound to a physicsHandler. physicsHandler.setEntity(sprite); ...
3
votes
3answers
212 views

Scaling Sound Effects and Physics with Framerate

(I'm using XNA and C#) Currently, my game (a shooter) runs flawlessly with 60 FPS (which I developed around). However, if the framerate is changed, there are two major problems: Gunshot sound ...
2
votes
2answers
281 views

Procedural generation of physics-enabled structures (in a 2D world)

Is it possible to procedurally generate stable structures out of rigidbody objects at a reasonable runtime speed? Imagine Angry Birds's levels kind of structures but generated procedurally.
6
votes
4answers
714 views

Sharing data between graphics and physics engine in the game?

I'm writing the game engine that consists of few modules. Two of them are the graphics engine and the physics engine. I wonder if it's a good solution to share data between them? Two ways (sharing ...
1
vote
1answer
379 views

Point inside Oriented Bounding Box?

I have an OBB2D class based on SAT. This is my point in OBB method: public boolean pointInside(float x, float y) { float newy = (float) (Math.sin(angle) * (y - center.y) + Math.cos(angle) * ...
1
vote
2answers
236 views

Perpendicularity of a normal and a velocity?

I'm trying to fake angular velocity on my vehicle when it hits a wall by getting the dot product of the normal of the edge the car is hitting and the vehicle's velocity: Vector2D normVel ...
1
vote
1answer
540 views

How do 2D physics engines solve the problem of resolving collisions along tiled walls/floors in non-grid-based worlds?

I've been working on implementing my SAT algorithm which has been coming along well, but I've found that I'm at a wall when it comes to its actual use. There are plenty of questions regarding this ...
1
vote
3answers
291 views

What different ways are there to model restitution in a physics engine?

In my physics engine I give a body a value for restitution between 0 and 1. When two bodies collide there seems to be different views on how the restitution of the collision should be calculated. To ...
1
vote
1answer
198 views

Who should respond to collision: Unit or projectile?

In an RTS if a projectile hits a unit. Who should handle the collision? If projectile handles the collision, it must be aware of all possible types of units, to know what damage to inflict. For ...
1
vote
1answer
276 views

What is going on in this SAT/vector projection code?

I'm looking at the example XNA SAT collision code presented here: http://www.xnadevelopment.com/tutorials/rotatedrectanglecollisions/rotatedrectanglecollisions.shtml See the following code: private ...
1
vote
3answers
531 views

Implementing distance joint

I would like to implement something that behaves much like a distance joint / revolute joint in Box2D, however I do not want to throw a whole physics engine at this problem. I'm curious where I might ...
4
votes
4answers
727 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 ...
3
votes
1answer
1k views

Engine for 2D Top-Down Physics-Based Skeletal Animation

I just watched at the Sui Generis video, and was completely amazed. Specifically, the part where the big troll thing is beating up the player with his flail. This got me really excited, and I would ...
2
votes
2answers
1k views

What is the best way to check if there is overlap between player and static, non-collidable items in bullet physic engine

I'd like to add non collidable objects (eg: power ups, items, ...) in a game world using Bullet Physics Engine and to know if there is collision between player and them. Some info : there is a lot ...
1
vote
1answer
141 views

Help with Collision Resolution?

I'm trying to learn about physics by trying to make a simplified GTA 2 clone. My only problem is collision resolution. Everything else works great. I have a rigid body class and from there cars and ...
0
votes
1answer
211 views

Player Movement DirectX

I'm reading on a Book that's about Gamedevelopment with C++ and DirectX 9. There is something that interrests me: It says that playermovements are increasing with the power of the CPU. Becouse a ...
1
vote
1answer
1k views

2D OBB collision detection, resolving collisions?

I currently use OBBs and I have a vehicle that is a rigid body and some buildings. Here is my update() private void update() { camera.setPosition((vehicle.getPosition().x * camera.getScale()) - ...
1
vote
1answer
226 views

Game Physics: Implementing Normal Reaction from ground correctly

I am implementing a simple side scrolling platform game. I am using the following strategy while coding the physics: Gravity constantly acts on the character. When the character is touching the ...
43
votes
3answers
1k views

How to determine which thrusters to turn on to rotate the ship?

The configuration of the ship changes dynamically, so I have to determine which thruster to turn on when I want to rotate the ship clockwise or counter clockwise. The thrusters are always axis aligned ...
1
vote
1answer
504 views

Rotating a cube using jBullet collisions

How would one go about rotating/flipping a cube with the physics of jBullet? Here is my Draw method for my cube object: public void Draw() { // center point posX, posY, posZ float ...
1
vote
1answer
156 views

Client Side Prediction for a Look Vector

So I am making a first person networked shooter. I am working on client-side prediction where I am predicting player position and look vectors client-side based on input messages received from the ...
6
votes
2answers
207 views

Timestep schemes for physics simulations

The operations used for stepping a physics simulation are most commonly: Integrate velocity and position Collision detection and resolution Contact resolution (in advanced cases) A while ago I ...
3
votes
1answer
239 views

Simulate 'Shock absorbtion' with tire rubber in PhysX (2.8.x)

This is a kinda tricky question and I fear there is no easy enough solution, but I figured I'd hit SE up before giving up on it and just doing what I can. A machine I am working on has no suspension ...
1
vote
2answers
124 views

How do I apply a force using the object direction and speed?

I have a 3D object moving and I need to be able to apply forces to it such as gravity. In 2D, I would simply store its movement in dx and dy, but since this is in 3D, I am using a Vector3D direction ...
6
votes
1answer
1k views

How do I detect ledges?

In my game, I'd like my character to be able to grab and hold onto ledges, and to be able to pull themselves up if there's room to do so. How do I detect if there's a ledge, and if the character has ...
2
votes
1answer
129 views

How do I prevent a KActor from changing the orientation of its Z-Axis?

So I have an object that inherits from KActor that I would like to behave as a dynamic physics object, but I want its Z-Axis to remain upright, but very stiffly. I've tried the bStayUpright that ...
1
vote
2answers
5k views

How to implement explosion in OpenGL with a particle effect?

I'm relatively new to OpenGL and I'm clueless how to implement explosion. So could anyone give me some ideas how to start? Suppose the explosion occurs at location $(x, y, z)$, then I'm thinking of ...
5
votes
3answers
741 views

'Spring' physics

I'm trying to put together a struct or a method of some sort that will allow me to check the relative position between two objects, and if they're too far apart, apply a force that will draw them ...
1
vote
1answer
902 views

Farseer Physics for Xna missing ConvertUnits class

Im using Farseer Physics with Xna 4.0. Im following a starter guide. It said that to draw, I need to convert the meters to pixels with the ConvertUnits namespace. I looked through all of the engine, ...
3
votes
1answer
2k views

Nape physics - Moving a body

Hey I'm currently getting started with physics engines and I set up a body (box shaped) which represents my character. Question: Which methods can I use to move a Nape.Body aka my char? I tried so ...
0
votes
2answers
654 views

Circle physics and collision using vectors

This is a problem I've been having, When making a set number of filled circles at random locations on a JPanel and applying a gravity (a negative change in the y), each of the circles collide. I want ...
2
votes
3answers
2k views

Game physics / 2D Collision detection AS3

I know there are some methods you can use like hittestPoint and so on, but I want to see where my movieclip colliedes with another another movieclip. Any other methods I can use? by any chance does ...
-1
votes
3answers
522 views

Can these game be fully coded in html5/javascript? [closed]

I mean the mechanics of the game. Would it be possible? -Pokemon GBA series, rendering the world would be easy, but what about battle mechanics? -MapleStory, after seen dragonbound.net which is an ...