# Tagged Questions

35 views

### Having problems with collision response (SAT)

i been playing around with SAT collision, and figured out the most part. (By copying/writing codes from countless sites). The SAT collision detection works, since it detects a collision. Now the MTV ...
79 views

### How do I handle this type of collision?

So I've been messing around with simple game development for a while and just found an interesting game idea here . I'm using SFML 2.1 with C++ and so far I have a tilemap in a VertexArray using a ...
77 views

### Identifying groupings of objects

I have a cloud of objects, each with a 3D position, and I want to pick out tight groups of these objects. Specifically, I want to find all objects which form a grouping of radius r within a large ...
46 views

### How to Calculate K-Dops Faster

Ok so I have my general understanding of K-Dops for collision detection. I understand how to calculate them. I also understand the super slow way of recalculating them. Example: I have a simple ...
190 views

### How and when to choose which objects to run collision tests on?

This might be problem with plenty of good solutions, but it's all not very clear to me, so I though I could ask and probably get some good hints. I'm having trouble figuring out how to handle ...
38 views

### Bullet Physics ConvexDecomposition?

I've looked at Bullet Physics ConvexComposition Demo and would like to implement that in my game but the code is so undescriptive and it's hard to understand what is going on. Would any of you people ...
52 views

### Load Meshes with Bullet Physics

I just started implementing some physics in my game with Bullet Physics and I was just wondering how would i use bullet physics to load in meshes. For my for DirectX I load in x files into a ...
218 views

### How can I improve my collision detection's performance?

I'm new to programming and want to speed up the collision detection in my C++ 2D platformer game engine. Currently, only the player's collision detection works: Every frame, the player's update ...
88 views

### How can I align a 2D object properly using tilemap collision

I'm making a mario clone, and I have been working on the collision but I can never seem to get it right. I started out with "true/false" collision, aligning the player at it's last position, and as ...
168 views

### How to architect collision detection in SFML

I have a pretty simple game engine that I'm making for a 2d platformer game. I don't want it to be super advanced, but it does have some basic properties. Most important to this question is a class ...
70 views

### Collision detection in seemingly random locations [closed]

I have a square that moves around with user input and should return to top left of screen when it collides with one of the rectangles on the screen. It works fine when the the rectangles are not ...
467 views

### Triangle-triangle continuous collision detection

I am making a 3D game engine and I use continuous collision detection. I am using Sphere-Trees to cull primitive collision checks to a minimum. However, I'd like to perform continuous ...
279 views

### C++ FPS game collision detection with partitioning system or physics engine? [closed]

I'm working on a small FPS game (as a hobby and for learning purposes, nothing else) built with C++ in OpenGL (from scratch). Documenting online on the kind of strategy someone would approach with ...
148 views

### Collision detection - make sure the player touches the object exactly

I know this is really something I should be able to figure out on my own, but a solution is evading me. Okay, here are a few relevant parts of my code. bool Game::Col(int x1,int y1,int w1,int h1, ...
160 views

### Simple collision detection implementation [closed]

I'm making a game with C++ where the program extracts the lines out of an image (via openCV), stores them in an std::vector< std::vector< int > > and the builds a tile map out of it which is ...
95 views

### Floating point precision issue with Box2D

I'm using Box2D and I am putting edge tiles as b2Bodies so that the tile world can have physics: The problem is that there are 3 b2_kinematic bodies under the player right beside each other. Every ...
77 views

### When and how should I update my collision grid?

When and how should I update my collision grid? Current implementation: buildGrid(): add all entities with collision to the grid handleCollision(timePerFrame, entities): handle all collisions ...
198 views

### Collision Shapes Abstraction Design

Straight to the facts. I have a base CEntity class for different entities in my game: Static entities ( those do not move, simply props and items ) Dynamic entities ( these move, jump ) Each of ...
384 views

### implementing collision detection and handling for tiled 2D world with smooth wall sliding

Im using SFML 2.1 for graphics and my game structure follows SFML book quite closely (SceneGraph implementation etc) My world consists mostly of characters (around 1-400, moving around) and tiles ...
388 views

### Finding Z given X & Y coordinates on terrain?

I need to know the most efficient way of finding Z given X & Y coordinates on terrain. My terrain is set up as a grid, each grid block consisting of two triangles which may be flipped in any ...
899 views

### Pixel Perfect Collision Detection in Cocos2dx

I am trying to port the pixel perfect collision detection in Cocos2d-x the original version was made for Cocos2D and can be found here: ...
280 views

### Collision Detection: Simulation Inexplicably Slowing Down/How To Efficiently Calculate Extremes In Each Dimension

BACKGROUND: As discussed here: Fast 2D collision detection in an unbounded space I am working on a collision detection algorithm for a simulation. The catch that makes this case unique is that the ...
175 views

### Why is my collision detection not accurate?

After trying and trying, I still cannot understand why the leg of character exceeds the wall but no clipping issue when I hit the wall from below. How should I fix it to make him stand still on the ...
1k views

### Optimizing collision engine bottleneck

If this is your first time on this question, I suggest reading the pre-update part below first, then this part. Here's a synthesis of the problem, though: Basically, I have a collision detection ...
252 views

### 2D collision resolution: works on each axis individually, but not with both combined

My collision detection method is solid and detects box to box collision every time. Then comes the resolve part which I'm struggling with quite a bit. It works perfectly when I'm manipulating the ...
337 views

### Efficient Collision Detection With Numerous Objects at Once [duplicate]

I am developing a 2D game with very large levels in which two teams(around 200 objects per team) fight against each other in planes, tanks, turrets,...etc. With every entity shooting bullets at their ...
68 views

### Implementing Frame of reference for physics calculations

How would I alter physical calculations to account for frame of reference of a physical body? Currently I have a world that is a collection of rigid body objects that act on each other. There is no ...
145 views

### Object Detection

I'm building a collision system for my 2D game, broadphasing (sweep and prone + pair detection) works. But I don't know how to separate pickup objects, tiles and the player from each other. My ...
820 views

### Pong collision detection

I am making Pong... again. Anyway, the collision detection. In the past, I had gotten it working, but it used a bunch of globals, and other nasty things. This time, I am trying it where I have a ...
740 views

### UML Class Diagrams for 2D platformer Games? [closed]

I have to develop a small arcade game in C++ for a college assignment using a 2D Game Engine my teacher coded. What would be the best way to make a UML class diagram for it? It's very basic stuff but ...
102 views

### GameTimer too fast, Objects staying intersected and rand not returning value inbetweem min and max [closed]

So I'm developing a game called PongBreakout in c++ using a game engine i got from uni (when i was there..) I've got a few problems with my game that i'm struggling to fix and need some help to figure ...
932 views

### How to do collision detection in 3D using bounding boxes?

I am using c++ in visual studio 2010 with opengl. I am trying to make a programme that has 2 boxes that are able to be stacked on top of each other but I am having some trouble with the collision ...
216 views

### 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 ...
668 views

### AABB-AABB sliding collision response

I have many objects with AABBs and a player surrounded in an AABB. If I represent my player with a point everything works smooth with detection and wall sliding as a response (for example what wall ...
172 views

### Sketchy results from ray-plane intersection code

I've set up a demo with simple first-person controls using C++ and OpenGL, and it seems to work reasonably well. My goal is this: when the player looks at a plane and clicks the left mouse button, ...
2k views

### Collision detection - Smooth wall sliding, no bounce effect

I'm working on a basic collision detection system that provides point - OBB collision detection. I have around 200 cubes in my environment and I check (for now) each of them in turn and see if it ...
631 views

### Online MMO collision detection for players & walls

Let's assume the following: I have a server which stores the player's position (float x, float y, float z) Client sends the server it's updated position ever 250ms or so. Server has bounding boxes ...
540 views

### Collision detection for 2D RTS game in C++

I'm currently working on a real time strategy game in C++, and I need to implement a collision detection algorithm. I need to have a very efficient algorithm because this game will be running on ...
354 views

### Min/Max of two vectors?

This seems like a simple question, but i'm having trouble searching the internet for it. In XNA, during a collision detecting method, I would determin the minimum of some vectors. // Get the minimum ...
94 views

### Collision planes confusion

I'm following this tutorial by thecplusplusguy and in the linked video he explain that for example for the world basement and walls we need to create the actual rendered (shown to the player) walls ...
121 views

### enemy behavior with boundary to change direction

I'm doing space shooter kind of game, the logic is to reflect the enemy if it hits the boundary. With my logic, sometimes enemy behaves like flickering instead of changing the velocity. It's like ...
99 views

### Hit Detection When rotating the camera

This bug/feature has been plaguing me for a while and i want to know the best way to fix it. I'm testing simple hit detection with a wall, like: if (Forward button) if(Inv.w.z < -49 || ...
407 views

### High CPU usage on Pong clone

I just made my first game, a clone of Pong, using OpenGL and C++. But its using ~50% of the CPU, which I guess is very high for a game like this. How can I improve that? Can you please look up my code ...
3k views

### Fast, accurate 2d collision

I'm working on a 2d topdown shooter, and now need to go beyond my basic rectangle bounding box collision system. I have large levels with many different sprites, all of which are different shapes and ...
389 views

### 2D SAT Collision Detection not working when using certain polygons (With example)

My SAT algorithm falsely reports that collision is occurring when using certain polygons. I believe this happens when using a polygon that does not contain a right angle. Here is a simple diagram of ...
217 views

### Checking collision of bullets and Asteroids

I'm trying to detect collision between two list of bullets and asteroids. The code works fine, but when the bullet intersects with an asteroid, and that bullet passes through another asteroid, the ...
62 views

### obb vs obb and resolve/response for 2d space game [duplicate]

Possible Duplicate: OBB vs OBB Collision Detection How can i detect if an rotated obb intersects another rotated obb and resolve it so both obb objects dont go further into each other. I ...
1k views

### Circle-Rectangle collision resolution

I have a non axis aligned rectangle, like a car, in my game. I have to check and resolve the collision between the rectangle and circle, which is stationary. I have found lots of ways to determine ...