# Tagged Questions

A process of adjusting game objects position after collision.

186 views

### How do you get the collision plane when using AABBs? [duplicate]

My collision detection initially seemed to work well enough, but my answer to this question shows that I have went with SAT testing now instead. My goal was to find the plane at which to slide the ...
227 views

### Simple Bounding Box Multiple Collision problem

I'm making my first game, and in it I use a moving ball to hit static blocks (kinda like breakout). Basically, I loop through all of the static blocks on the screen each frame, update the position ...
235 views

### Determining which edge a collision occurred on in a platformer

First of all, this will be Open Source, and you will be mentioned for the help. We've been programming a Super Mario Remake for the iPhone with Cocos2d for school. It looks pretty great, and we ...
3k views

### Hexagon collision detection for fast moving objects?

A object has a position and a speed vector. Usually only the position is used to check if two objects collide, this is problematic for very fast moving objects as it can happen that the object moves ...
285 views

### Is it possible to get the colliding sides using the separating axis theorem?

The title says it all, is it even possible to get the colliding sides? I'm checking for collisions between two OABBs, which works fine using SAT. Now I want to set the moving object's velocity to the ...
336 views

### When to detect and respond to collisions?

I've usually implemented collision detection like this in the past: Move entity Check if it collides with anything Resolve the collision by moving it back That's also the approach employed by most ...
411 views

### How to deal with pushing objects out of collision in a physics engine

I'm developing a 3D physics engine (I know, I should use one of the many good existing physics libraries, however my collision detection is optimised for objects with highly ordered highly complex ...
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### How was traditional 2D collision detection/resolution being done? [closed]

Just out of pure curiosity, I'm wondering how classic 2D games of the 80s/90s (The Legend of Zelda, Super Mario, Warcraft, ...) approached collision detection/resolution. For some reason I can't ...
322 views

### XNA Collision is quircky/wobbly, how to improve?

I am sorry if this was already answered but I couldn't find the answer. So I am doing a tile based platformer and when I was making collision I had quiet a struggle I looked here and googled for ...
948 views

### Differences between Overlap and Intersection testing?

I have heard of techniques such as overlap testing and intersection testing for collision detection and collision resolution. I looked up on the two techniques, but I don't see what differences they ...
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### Should I negate a variable or use absolute value? [closed]

this is how i was chaning ball postion if(...) //if ball goes to left of screen dx = -dx if(...) //if ball goes right of screen dx = -dx; i found some people using math.abs to move ball postion....
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### Help me please to choose proper path-finding algorithm

I am new to game development and just want to ask for advice. I need to know which path-finding algoritm will be suitable for my scenario: Units - any shape. But in most cases rectangles of ...
248 views

### How can I easily model semi-realistically human movement and collision in a 2D game?

I am writing a sports simulation game in which the simulated players will interact physically with each other (i.e. tackle, push, bump...) as well as do individual actions such as changing direction ...
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### Resolving 2D Collision with Rectangles

For about a week I've been trying to grasp the basics of collision, but I've been driven to the point of wanting to just give up on everything when it comes to collision. I just don't understand it. ...
91 views

### collision between two objects

to test collision i am using intersect function. if(this.getBounds_ball().intersects(this.getBounds_rect())) { but the problem is i dont know how to test where the ball is collision from. i was ...
84 views

### collision test between ball and rect [closed]

need help with collision between ball and rect. i dont know how to test if ball hit the rec from top, bottom, right or left. x = ball x y = ball y radius = ball width and height rx = rect x ry = rect ...
331 views

### Pixel perfect collisions for platforms

i'm trying to do a pixel perfect collision but i don't know how to handle collisions when there is a jump . Here i have one image of a sample map: But maybe I've done a bad supposing all pixel like ...
495 views

### Tile Based Collision Checking In Java?

I have my map stored in 2 arrays: Tiles : Tile names TileTypes : SOLID or BASIC I want to be able to walk through BASIC Tiles (Like ground tiles). But not the SOLID Tiles (Like wall tiles). I ...
142 views

### Collision Response: game character vs. density function

Introduction I am working on my own "novelty" game-engine project, where the world is represented by a continuous density function. It has only one interface, a function that returns the density at a ...
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### Collision Resolution: How to avoid Interpenetration/Tunneling Caused by Prior Collision Handling? [duplicate]

My game processes world collisions followed by entity collisions. The problem here is that entities can break through walls the next frame when world checks are run again as a result of the prior ...
390 views

### Get intersected volume of two planes in 3D

I'm working on AABB - AABB collision response and I'm having trouble figuring one part out. My situation is as follows (see image). I have a player AABB (blue) and an object which collides (brown). ...
990 views

### How to detect screen boundary using AndEngine GLES1?

I am using the AnalogOnScreenControl to move my sprite around the screen. I would like to restrict the sprite so it can not move outside the screen boundaries. I have tried putting a line at the ...
763 views

### 2D tile-based collisions: using different methods by tile?

I'm trying to write a collision handling method that handles each of the 9 potentially colliding tiles (the player's and the 8 around him) differently according to a "CollisionType" value attached to ...
435 views

### Collision in PyGame for spinning rectangular object.touching circles

I'm creating a variation of Pong. One of the differences is that I use a rectangular structure as the object which is being bounced around, and I use circles as paddles. So far, all the collision ...
2k views

### How to calculate collision normal between two AxisAlignedBox's?

I'm writing a physics simulation in Ogre3D and I'm trying to figure out how to calculate the collision normal between two Ogre::AxisAlignedBox's. I am checking for collisions using the "intersects" ...
4k views

### Resolving a collision with forces

In my 2D physics engine, I can detect AABB vs AABB collisions, and resolve them by finding the shortest penetration vector and adding it to the AABB's position. Doing this "pushes" the first AABB ...
351 views

### Slide effect in voxel collisions

I'm making a voxel engine, and I'm trying to figure out the right way to make efficient collisions with a slide response (making the player slide against the wall). Currently my collisions are pretty ...
434 views

### Calculating impulse propagation through a rigid body after a collision

I'm working on a game. I need to work out what the impulse is at different points on a body as a result of a collision. For example, in the following diagram, if there is a collision that results in ...
1k views

### Find the Contact Normal of Rectangle Collision

It seems a lot of people have asked similar questions on this site, and every time it seems like a whole bunch of answers that don't work are given. Basically, I have two rectangles (AABBs) that ...
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### Meaning of offset in pygame Mask.overlap methods

I have a situation in which two rectangles collide, and I have to detect how much did they collide so so I can redraw the objects in a way that they are only touching each others edges. It's a ...
221 views

### Confusing with an articles wording on Clamping a Vector2

I have been reading an article on Collision Detection and how to resolve it. http://www.wildbunny.co.uk/blog/2011/04/20/collision-detection-for-dummies/ In the section describing an AABB vs Circle, ...
467 views

### Separating axis theorem implementation flaky minimum translation vector based on triangle orientation

I've implemented some collision detection using separating axis theorem. Works fine for axis-aligned rectangles and two out of four possible right triangle orientations. For some reason when the ...
1k views

### XNA 4.0 / C# Collision Response

Okay, this is really starting to annoy me. First of all, detecting collisions is nice and easy. I have a list of tiles, and a player. The player and each tile have their own rectangles. (The tiles ...
200 views

### Why does this collision detection & resolution code only work for one side?

I am having a bit of trouble with my collision detection. It only works correctly for the right side, meaning, if I enter the tile from any other side, it brings me to the right side. Here is my code:...
519 views

### How to handle collision resolution in a top-down car game?

I have a top-down car game which takes place in an arena. The game is very very light on physics, so I'm not actually using a physics engine. The cars' movement is mostly managed by a struct I called ...
195 views

### Why is my collision resolution failing on the corners?

I'm tearing my hair out trying to work out how to handle my collision resolution at the corners of the rectangles that I'm colliding with. The code that I'm working with is: class Player(object): ...
319 views

### My 2D collision code does not work as expected. How do I fix it?

I have a simple 2D game with a tile-based map. I am new to game development, I followed the LazyFoo tutorials on SDL. The tiles are in a bmp file, but each tile inside it corresponds to an internal ...
643 views

### Collision resolution - Character walking on ascendent ground

I don't know if the solution to this problem is quite straight-foward but I really don't know how to handle collision resolution on a game where the player walks on an ascendent floor which is not ...
611 views

### How can I get accurate collision resolution on the corners of rectangles?

I have a working collision system implemented, and it's based on minimum translation vectors. This works fine in most cases except when the minimum translation vector is not actually in the direction ...
187 views

### Typical collision detection

I would like to know how is the typical collision detection of most games. For example, you control a character which can move in 2 dimensional directions (except up and down). Now lets asume he walks ...
553 views

### How to make a stack stable? Need help for an explicit resting contact scheme (2-dimensional)

Previously, I struggle with the sequential impulse-based method I developed. Thanks to jedediah referring me to this paper, I managed to rebuild the codes and implement the simultaneous impulse based ...
638 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 ...
407 views

### Move penetrating OBB out of another OBB to resolve collision

I'm working on collision resolution for my game. I just need a good way to get an object out of another object if it gets stuck. In this case a car. Here is a typical scenario. The red car is in ...
165 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 ...
2k views

### Collision Detection Game Design and Architecture

I've reading some articles about collision detection. My question here is about ideas on the design for it. Baically I have a C++ game that has a main loop with entities with an update method. Based ...
2k 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()) - ...
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### XNA 2D vehicle wall collisions

I am attempting to implement collisions for my truck game, where the truck can drive around the world and hit walls surrounding the level and various randomly placed walls within the level. I am able ...
730 views

### Circle vs Edge collision detection / resolution [closed]

I made a javascript class Ball.js that handles physics interactions betweens balls as well as painting. In the v1.0, the ball vs ball collision detection and resolution is well handled. In the next ...