collision-detection

What is the best way to check collision of huge number of circles? It's very easy to detect collision between two circles, but if we check every combination then it is O(n 2 ) which definitely not an optimal solution. We can assume that circle object has following properties: Coordinates Radius Velocity Direction Velocity is constant, but direction can change. I've come up with two solutions, but maybe there are some better solutions. Solution 1 Divide whole space into overlapping squares and check for collision only with circles that are in the same square. Squares need to overlap so there

I have been given an assignement for a graphics module, one part of which is to calculate the minimum bounding ellipse of a set of arbitrary shapes. The ellipse doesn't have to be axis aligned. This is working in java (euch) using the AWT shapes, so I can use all the tools shape provides for checking containment/intersection of objects. Jacob You're looking for the Minimum Volume Enclosing Ellipsoid , or in your 2D case, the minimum area. This optimization problem is convex and can be solved efficiently. Check out the MATLAB code in the link I've included - the implementation is trivial and

I'm trying to use Physics2D.Raycast in order to check if the player is on the ground (I know that there are other approaches to check if the player is on the ground but I think that the raycast is the most reliable). The problem is that in my scenario it returns the player itself as hit and I really don't understand why and what should I do. My code (in PlayerController ) is the following: public bool IsGrounded () { Bounds bounds = this.playerCollider.bounds; Vector3 rayOrigin = bounds.center; rayOrigin.y -= bounds.extents.y; RaycastHit2D hit = Physics2D.Raycast (rayOrigin, Vector2.down, 0.1f

I have made a simple 2D state change game using Bucky's slick Java tutorials, I modified this game and now want to set collisions on the map so that my player can not go through the house on the map. I think I kind of have a idea of how collisions work: you make 2 rectangles using the following code: public Rectangle getBounds() { return new Rectangle(x, y, width, height); } 1 for the player and 1 for the obstacle, how would I put this into my code and how would I tell java that the rectangle for the obstacle is different to the player rectangle? Then after making the 2 rectangles I would set

Ok so I am working on a game on Android. I need to implement pixel perfect collision detection. I already have the bounding boxes set up around each of the images, each bounding box is transformed to match the current rotation of the image. That all works great. I also have the pixel data from each bitmap stored in an array. Can someone help me figure out the most efficient way to go about detecting if the pixels overlap? Thanks in advance for any help! The basic idea is to create a bitmask for each object where you indicate in each pixel if the object is actually there or not. Then you