Search Results

Search found 1897 results on 76 pages for 'beat detection'.

Page 22/76 | < Previous Page | 18 19 20 21 22 23 24 25 26 27 28 29  | Next Page >

  • How to find 2D grid cells swept by a moving circle?

    - by Nevermind
    I'm making a game based on a 2D grid, with some cells passable and some not. Dynamic objects can move continuously, independent of the grid, but need to collide with impassable cells. I wrote an algorithm to trace a ray against the grid, that gives me all cells that ray intersects. However, actual object are not point-sized; I'm currently representing them as circles. But I can't figure out an effective algorithm to trace a moving circle. Here's a picture of what I need: The numbers show in what order the circle collides with grid cells. Does anybody know the algorithm to find these collisions? Preferably in C#. Update The circle can be bigger than a single grid cell.

    Read the article

  • Why does the player fall down when in between platforms? Tile based platformer

    - by inzombiak
    I've been working on a 2D platformer and have gotten the collision working, except for one tiny problem. My games a tile based platformer and whenever the player is in between two tiles, he falls down. Here is my code, it's fire off using an ENTER_FRAME event. It's only for collision from the bottom for now. var i:int; var j:int; var platform:Platform; var playerX:int = player.x/20; var playerY:int = player.y/20; var xLoopStart:int = (player.x - player.width)/20; var yLoopStart:int = (player.y - player.height)/20; var xLoopEnd:int = (player.x + player.width)/20; var yLoopEnd:int = (player.y + player.height)/20; var vy:Number = player.vy/20; var hitDirection:String; for(i = yLoopStart; i <= yLoopEnd; i++) { for(j = xLoopStart; j <= xLoopStart; j++) { if(platforms[i*36 + j] != null && platforms[i*36 + j] != 0) { platform = platforms[i*36 + j]; if(player.hitTestObject(platform) && i >= playerY) { hitDirection = "bottom"; } } } } This isn't the final version, going to replace hitTest with something more reliable , but this is an interesting problem and I'd like to know whats happening. Is my code just slow? Would firing off the code with a TIMER event fix it? Any information would be great.

    Read the article

  • Using Bullet physics engine to find the moment of object contact before penetration

    - by MooMoo
    I would like to use Bullet Physics engine to simulate the objects in 3D world. One of the objects in the world will move using the position from 3D mouse control. I will call it "Mouse Object" and any object in the world as "Object A" I define the time before "mouse object" and "Object A" collide as t-1 The time "mouse object" penetrate "Object A" as t Now there is a problem about rendering the scene because when I move the mouse very fast, "Mouse object" will reside in "Object A" before "Object A" start to move. I would like the "Mouse Object" to stop right away attach to the "Object A". Also If the "Object A" move, the "Mouse object" should move following (attach) the "Object A" without stop at the first collision take place. This is what i did I find the position of the "Mouse Object" at time t-1 and time t. I will name it as pos(t-1) and pos(t) The contact time will be sometime between t-1 to t, which the time of contact I name it as t_contact, therefore the contact position (without penetration) between "Mouse object" and "Object A" will be pos(t_contact) then I create multiple "Mouse object"s using this equation pos[n] = pos(t-1) * C * ( pos(t) - pos(t-1) ) where 0 <= C <= 1 if I choose C = 0.1, 0.2, 0.3,0.4..... 1.0, I will get pos[n] for 10 values Then I test collision for all of these 10 "Mouse Objects" and choose the one that seperate between "no collision" and "collision". I feel this method is super non-efficient. I am not sure the way other people find the time-of-contact or the position-of-contact when "Object A" can move.

    Read the article

  • How to handle circle penetration

    - by Kaertserif
    I've been working on cirlce to circle collision and have gotten the intersection method working correctly, but I'm having problems using the returned values to actually seperate the circles from one another. This is the method which calculates the depth of the circle collision public static Vector2 GetIntersectionDepth(Circle a, Circle b) { float xValue = a.Center.X - b.Center.X; float yValue = a.Center.Y - b.Center.Y; Vector2 depth = Vector2.Zero; float distance = Vector2.Distance(a.Center, b.Center); if (a.Radius + b.Radius > distance) { float result = (a.Radius + b.Radius) - distance; depth.X = (float)Math.Cos(result); depth.Y = (float)Math.Sin(result); } return depth; } This is where I'm trying to apply the values to actually seperate the circles. Vector2 depth = Vector2.Zero; for (int i = 0; i < circlePositions.Count; i++) { for (int j = 0; j < circlePositions.Count; j++) { Circle bounds1 = new Circle(circlePositions[i], circle.Width / 2); Circle bounds2 = new Circle(circlePositions[j], circle.Width / 2); if(i != j) depth = CircleToCircleIntersection.GetIntersectionDepth(bounds1, bounds2); if (depth != Vector2.Zero) { circlePositions[i] = new Vector2(circlePositions[i].X + depth.X, circlePositions[i].Y + depth.Y); } } } If you can offer any help in this I would really appreciate it.

    Read the article

  • How to design 2D collision callback methods?

    - by Ahmed Fakhry
    In a 2D game where you have a lot of possible combination of collision between objects, such as: object A vs object B = object B vs A; object A vs object C = object C vs A; object A vs object D = object D vs A; and so on ... Do we need to create callback methods for all single type of collision? and do we need to create the same method twice? Like, say a bullet hits a wall, now I need a method to penetrate the wall for the wall, and a method to destroy the bullet for the bullet!! At the same time, a bullet can hit many objects in the game, and hence, more different callback methods!!! Is there a design pattern for that?

    Read the article

  • Checking collision of bullets and Asteroids

    - by Moaz ELdeen
    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 code gives an assertion, and it says about it can't increment the iterator. I'm sure there is a small bug in that code, but I can't find it. for (list<Bullet>::iterator itr_bullet = ship.m_Bullets.begin(); itr_bullet!=ship.m_Bullets.end();) { for (list<Asteroid>::iterator itr_astroid = asteroids.begin(); itr_astroid!=asteroids.end(); itr_astroid++) { if(checkCollision(itr_bullet->getCenter(),itr_astroid->getCenter(), itr_bullet->getRadius(), itr_astroid->getRadius())) { itr_astroid = asteroids.erase(itr_astroid); } } itr_bullet++; }

    Read the article

  • Pygame - CollideRect - But How Do They Collide?

    - by Chakotay
    I'm having some trouble figuring out how I can handle collisions that are specifically colliding on the top or bottom a rect. How can specify those collisions? Here's a little code snippet to give you an idea of my approach. As it is now it doesn't matter where it collides. # the ball has hit one of the paddles. send it back in another direction. if paddleRect.colliderect(ballRect) or paddle2Rect.colliderect(ballRect): ballHitPaddle.play() if directionOfBall == 'upleft': directionOfBall = 'upright' elif directionOfBall == 'upright': directionOfBall = 'upleft' elif directionOfBall == 'downleft': directionOfBall = 'downright' elif directionOfBall == 'downright': directionOfBall = 'downleft' Thanks in advance. **EDIT** Paddle rect: top ____ | | | | | | Sides | | ---- bottom I need to know if the ball has hit either the top or the bottom.

    Read the article

  • Cocos2D - Detecting collision

    - by Grace
    I am a beginner in cocos2d and im facing a problem with detecting collision for my coins. Sometimes it works sometimes it doesn't. So basically, im creating a game which the user (ship) have to avoid the obstacles and collect coins on the way. The collision of the obstacle works well but not for the coins. I was thinking maybe the loops for creating many coins is the problem but im not sure. Can anyone help? My codes: - (void)update:(ccTime)dt{ double curTime = CACurrentMediaTime(); if (curTime > _nextBridgeSpawn) { float randSecs = [self randomValueBetween:3.0 andValue:5.0]; _nextBridgeSpawn = randSecs + curTime; float randX = [self randomValueBetween:50 andValue:500]; float randDuration = [self randomValueBetween:8.0 andValue:10.0]; CCSprite *bridge = [_bridge objectAtIndex:_nextBridge]; _nextBridge++; if (_nextBridge >= _bridge.count) _nextBridge = 0; [bridge stopAllActions]; bridge.position = ccp(winSize.width/2, winSize.height); bridge.visible = YES; [bridge runAction:[CCSequence actions: [CCMoveBy actionWithDuration:randDuration position:ccp(0, -winSize.height)], [CCCallFuncN actionWithTarget:self selector:@selector(setInvisible:)], nil]]; this is where i declare my coins (continued from the update method) int randCoin = [self randomValueBetween:0 andValue:5]; _coin = [[CCArray alloc] initWithCapacity:randCoin]; for(int i = 0; i < randCoin; ++i) { coin = [CCSprite spriteWithFile:@"coin.png"]; coin.visible = NO; [self addChild:coin]; [_coin addObject:coin]; } float randCoinX = [self randomValueBetween:winSize.width/5 andValue:winSize.width - (border.contentSize.width *2)]; float randCoinY = [self randomValueBetween:100 andValue:700]; float randCoinPlace = [self randomValueBetween:30 andValue:60]; for (int i = 0; i < _coin.count; ++i) { CCSprite *coin2 = [_coin objectAtIndex:i]; coin2.position = ccp(randCoinX, (bridge.position.y + randCoinY) + (randCoinPlace *i)); coin2.visible = YES; [coin2 runAction:[CCSequence actions: [CCMoveBy actionWithDuration:randDuration position:ccp(0, -winSize.height-2000)], [CCCallFuncN actionWithTarget:self selector:@selector(setInvisible:)], nil]]; } } this is to check for collision (also in the update method) for (CCSprite *bridge in _bridge) { if (!bridge.visible) continue; if (CGRectIntersectsRect(ship.boundingBox, bridge.boundingBox)){ bridge.visible = NO; [ship runAction:[CCBlink actionWithDuration:1.0 blinks:5]]; } } } //this is the collision for coins which only work at times for (CCSprite *coin2 in _coin) { if (!coin2.visible) continue; if (CGRectIntersectsRect(ship.boundingBox, coin2.boundingBox)) { NSLog(@"Coin collected"); coin2.visible = NO; } } } Thank you.

    Read the article

  • Bitmap & Object Collision Help

    - by MarkEz
    Is it possible to detect when an object and a bitmap collide. I have an arraylist of sprites that I am shooting with an image. I tried using this method here but as soon as the bitmap appears the sprite disappears, this is in the Sprite class: public boolean isCollision(Bitmap other) { // TODO Auto-generated method stub if(other.getWidth() > x && other.getWidth() < x + width && >other.getHeight() > y && other.getHeight() < y + height); return true; }

    Read the article

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

    - by dreta
    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 TOI for two fast moving objects and everything is working smoothly. My issue now is that i can't figure out how to determine whether two fast moving objects should even be checked against each other in the first place. I'm using a quad tree for spacial partitioning and for each fast moving object, i check it against objects in each cell that it passes. This works fine for determining collision with static geometry, but it means that any other fast moving object that could collide with it, but isn't in any of the cells that are checked, is never considered. The only solution to this i can think of is to either have the cells large enough and cross fingers that this is enough, or to implement some sort of a brute force algorithm. Is there a proper way of dealing with this, maybe somebody solved this issue in an efficient manner. Or maybe there's a better way of partitioning space that accounts for this?

    Read the article

  • Android Bitmap: Collision Detecting

    - by Aekasitt Guruvanich
    I am writing an Android game right now and I would need some help in the collision of the Pawns on screen. I figured I could run a for loop on the Player class with all Pawn objects on the screen checking whether or not Width*Height intersects with each other, but is there a more efficient way to do this? And if you do it this way, many of the transparent pixel inside the rectangular area will also be considered as collision as well. Is there a way to check for collision between Bitmap on a Canvas that disregard transparent pixels? The class for player is below and the Pawn class uses the same method of display. Class Player { private Resources res; // Used for referencing Bitmap from predefined location private Bounds bounds; // Class that holds the boundary of the screen private Bitmap image; private float x, y; private Matrix position; private int width, height; private float velocity_x, velocity_y; public Player (Resources resources, Bounds boundary) { res = resources; bounds = boundary; image = BitmapFactory.decodeResource(res, R.drawable.player); width = image.getWidth(); height = image.getHeight(); position = new Matrix(); x = bounds.xMax / 2; // Initially puts the Player in the middle of screen y = bounds.yMax / 2; position.preTranslate(x,y); } public void draw(Canvas canvas) { canvas.drawBitmap(image, position, null); } }

    Read the article

  • 3D Mesh Collision Help

    - by BlackAfricano
    I am new to XNA (I have only been working in it for a countable number of weeks) as well as to these forums (I have only made 1-2 other posts), so this may seem like a strange request, but I am wondering if anybody knows about more advanced collision in XNA. So far I have only been able to figure out BoundingSphere's which seem to be the simplest of the methods, and I was thinking of looking more into BoundingBoxes because the game I have is a 2-3D platformer. The problem I realized was that if I wanted to get any more advanced than stages in the shape of a box, I would face some immediate dilemmas. I was hoping somebody here was knowledgeable on the subject and could inform me where I could get started learning how to do something like this: https://www.youtube.com/watch?v=ekMD_Gtt8d4 Although the game in this video isn't very pretty, the mesh collision looks like what I'm looking for. I am hoping for the most complete solution, if possible.

    Read the article

  • How would I detect if two 2D arrays of any shape collided?

    - by user2104648
    Say there's two or more moveable objects of any shape in 2D plane, each object has its own 2D boolean array to act as a bounds box which can range from 10 to 100 pixels, the program then reads each pixel from a image that represents it, and appropriatly changes the array to true(pixel has a alpha more then 1) or false(pixel has a alpha less than one). Each time one of these objects moves, what would be the best accurate way to test if they hit another object in Java using as few APIs/libraries as possible?

    Read the article

  • Using PhysX, how can I predict where I will need to generate procedural terrain collision shapes?

    - by Sion Sheevok
    In this situation, I have terrain height values I generate procedurally. For rendering, I use the camera's position to generate an appropriate sized height map. For collision, however, I need to have height fields generated in areas where objects may intersect. My current potential solution, which may be naive, is to iterate over all "awake" physics actors, use their bounds/extents and velocities to generate spheres in which they may reside after a physics update, then generate height values for ranges encompassing clustered groups of actors. Much of that data is likely already calculated by PhysX already, however. Is there some API, maybe a set of queries, even callbacks from the spatial system, that I could use to predict where terrain height values will be needed?

    Read the article

  • 3D Box Collision Data Import

    - by cboe
    I'm trying to implement a collision system using oriented bounding boxes, using a center for the box, it's extents as a 3D Vector and a rotation matrix, which is all stuff I picked up online and seem to be somewhat the standard. Detecting the center is no problem so I'm gonna leave these out here. My problem however is importing the data from a 3D file. Say I've placed a box with 2 units length on each side aligned to the world axis. The logic results here are extents of 1,1,1 and I use an identity matrix for rotation - easy. However I'm stuck when I rotate the box in the 3D program, say 30 degrees each axis. How would I parse the box? I only have these 8 vertices as information, and I guess what I would need to do is to find out the rotation of said box, apply it to the vertices so they are aligned to world axes and then calculate the extents out of that. How do I get the rotation of the box when I only have the vertex information of the box available?

    Read the article

  • Bitmap & Object Collision Help

    - by MarkEz
    Is it possible to detect when an object and a bitmap collide. I have an arraylist of sprites that I am shooting with an image. I tried using this method here but as soon as the bitmap appears the sprite disappears, this is in the Sprite class: public boolean isCollision(Bitmap other) { if(other.getWidth() > x && other.getWidth() < x + width && >other.getHeight() > y && other.getHeight() < y + height); return true; }

    Read the article

  • Elastic Collision Formula in Java

    - by Shijima
    I'm trying to write a Java formula based on this tutorial: 2-D elastic collisions without Trigonometry. I am in the section "Elastic Collisions in 2 Dimensions". In step 1, it mentions "Next, find the unit vector of n, which we will call un. This is done by dividing by the magnitude of n". My below code represents the normal vector of 2 objects (I'm using a simple array to represent the normal vector), but I am not really sure what the tutorial means by dividing the magnitude of n to get the un. int[] normal = new int[2]; normal[0] = ball2.x - ball1.x; normal[1] = ball2.y - ball1.y; Can anyone please explain what un is, and how I can calculate it with my array in Java?

    Read the article

  • Intersection of player and mesh

    - by Will
    I have a 3D scene, and a player that can move about in it. In a time-step the player can move from point A to point B. The player should follow the terrain height but slow going up cliffs and then fall back, or stop when jumping and hitting a wall and so on. In my first prototype I determine the Y at the player's centre's X,Z by intersecting a ray with every triangle in the scene. I am not checking their path, but rather just sampling their end-point for each tick. Despite this being Javascript, it works acceptably performance-wise. However, because I am modeling the player as a single point, the player can position themselves so that they are half-in a cliff face and so on. I need to model them as as a solid e.g. some cluster of spheres or a even their fuller mesh. I am also concerned that if they were moving faster they might miss the test altogether. How should I solve this?

    Read the article

  • XNA - Detect click on triangle/circle form of a texture

    - by chr1s89
    How can i detect clicks on a texture (will be a button in my game) that has a form of a triangle or circle. I know only the rectangle solution where u can use the positions + the width/height but this dont work for that because clicks will be detected at the transparent pixels. I heard of pixel-perfect collision is it the right way for this? It would be great if someone can give me a example for such a solution or other.

    Read the article

  • 2D Game Development dynamics in c++ [on hold]

    - by novice
    I am new to developing computer graphic applications in c++ using OpenGl. I want to develop games but I really am facing problems when it comes to understanding concepts like trajectory, collisions, gravity and also the use of various physics engines that are available. when i search the internet I kind of get lost because they aren't for beginners like me. There is some hardcore mathematics, physics and coding involved. I need to pick the concepts that are mostly needed in game dev like trajectory, collision etc. Any good tutorials that can help me out in picking these concepts from the start.

    Read the article

  • Detect rotated rectangle collision

    - by handyface
    I'm trying to implement a script that detects whether two rotated rectangles collide for my game. I used the method explained in the following article for my implementation in Google Dart. 2D Rotated Rectangle Collision I tried to implement this code into my game. Basically from what I understood was that I have two rectangles, these two rectangles can produce four axis (two per rectangle) by subtracting adjacent corner coordinates. Then all the corners from both rectangles need to be projected onto each axis, then multiplying the coordinates of the projection by the axis coordinates (point.x*axis.x+point.y*axis.y) to make a scalar value and checking whether the range of both the rectangle's projections overlap. When all the axis have overlapping projections, there's a collision. First of all, I'm wondering whether my comprehension about this algorithm is correct. If so I'd like to get some pointers in where my implementation (written in Dart, which is very readable for people comfortable with C-syntax) goes wrong. Thanks!

    Read the article

  • Make the player run onto stairs smoothly

    - by misiMe
    I have a 2D Platform game, where the player Always runs to the right, but the terrain isn't Always horizontal. Example: I implemented a bounding-box collision system that just checks for intersections with player box and the other blocks, to stop player from running if you encounter a big block, so that you have to jump, but when I put stairs, I want him to run smoothly just like he is on the horizontal ground. With the collision system you have to jump the stairs in order to pass them! I thought about generating a line between the edges of the stairs, and imposing the player movement on that line... What do you think? Is there something more clever to do?

    Read the article

  • Should my game handle collisions in the Player object?

    - by user1264811
    I'm making a 2D platform game. Right now I'm just working on making a very generic Player class. I'm wondering if it would be more efficient/better practice to have an ActionListener within the Player class to detect collisions with Enemy objects (also have an ActionListener) or to handle all the collisions in the main world. Furthermore, I'm thinking ahead about how I will handle collisions with the platforms themselves. I've looked into the double boolean arrays to see which tiles players can go to and which they can't. I don't understand how to use this class and the player class at the same time.

    Read the article

  • Collision for mobile game

    - by zemiguel12
    I'm writing a little game in as3 using Starling, and I need to check collision between 2 boats that can rotate. I don't need the pixel perfect collision, but bounds collision is not enough too. The boat look more or less like this: I was thinking about create one square on the back of the boat and a triangle on the front, than for each boat, check if the square collide with the other boat square or triangle, and the same for the triangle. I just don't know how to do that, I don't know if it's possible with the Shape.hitTest, or if it's the best way to do that. What can I do?

    Read the article

  • How to drop packets in a custom Intrusion Detection System

    - by tzoukos
    Hi there, I'm trying to build a custom Intrusion Detection and Prevention System (IDS/IPS). I found a great utility named ROPE which can scan the packet payload and drop the packet that doesn't follow the rules, set by a script. This serves my purpose completely, since what I want to do is check the payload for some specific text and then drop it or allow it ( the string feature in iptables wouldn't do me any good, because I want to check more than one string in tha payload, like usernames, id's, etc ). However, ROPE is really old and despite my many attempts I haven't managed to install it properly. Do you know any similar program that will help me drop packets in iptables depending on the payload? Any suggestion is greatly appreciated :)

    Read the article

< Previous Page | 18 19 20 21 22 23 24 25 26 27 28 29  | Next Page >