Vector 2d collision how to#
Vector 2d collision code#

That way when you use your color detection to check for collisions you can use the same information to get the normal. The fastest (in runtime) way would be to create a texture that holds this information. In order to get the correct reflection you will need to know the 'normal' of the wall you collide with. v being velocity, n being the normal of the wall scaled by your alignment with said normal. Your velocity after collision will essentially be v - n. It's definitely possible but it's not simple. Now, to get the actual reflected direction, take d and the newly created n and using the formula: e = d - 2 * (d ⋅ n) * n You can get it by taking the x and y components of c and creating the vector (y -x), which is the rotated version of it, and normalizing it. The normal vector is a vector with a length of 1, that's perpendicular to c. First you'll have to get the normal vector of c. First you'll have to convert line AB to a vector, let's call it c for convenience. Here line AB is the line segment, d is the car's direction and e is the direction you want to find. Luckily there's also a way to find this out, but it involves a bit of vector math, mainly the dot product. Next thing we need to now is in which direction it bounces us. So, now we know which line segment the car hit. You can also get the intersection's position, but it's not necessary to calculate it if your cars don't go with a relatively high speed (more than around the car's size every frame). Is greater than or equal to 0, the circle and the line intersect. From this site we see, that to determine whether a circle and a line intersects, we need the start and end points of the line ( (x1 y1) and (x2 y2) in order) and the radius of the circle ( r). Due to the way your cars look like, you could take a circle that fully encloses your car and do a collision check on each side of the polygon separately. If we take your original example, the polygon would look something like the following (I wasn't very exact, but you get the point): This can be done by an algorithm, but if you have only relatively few levels, then writing the tool may require more time than it saves over doing it by hand (This doesn't mean that you should just use a text-editor and estimate where the points are, you should write a program that helps you, but don't create an image analyzer). So, first thing you should do is to polygonize the racetrack. Remember, most players (if not all) don't go over game footage frame-by-frame doing pixel measurements to check whether the angles match up. You can approximate to get a good enough reflection angle. If both pixels are not completely transparent, (y - rectangleB.Top) * rectangleB.Width] (y - rectangleA.Top) * rectangleA.Width] Ĭolor colorB = dataB[(x - rectangleB.Left) + Get the color of both pixels at this pointĬolor colorA = dataA[(x - rectangleA.Left) + Check every point within the intersection bounds Int right = Math.Min(rectangleA.Right, rectangleB.Right) Int left = Math.Max(rectangleA.Left, rectangleB.Left) Int bottom = Math.Min(rectangleA.Bottom, rectangleB.Bottom) Int top = Math.Max(rectangleA.Top, rectangleB.Top) Find the bounds of the rectangle intersection

Vector 2d collision code#

I am going to use the following code to detect pixel collision: static bool IntersectPixels(Rectangle rectangleA, Color dataA, Hopefully someone would be able to explain.

Vector 2d collision how to#

provided an explanation of how to get the pixels color. How to perform the color check is for me still a question now. To get the pixel color under the vehicle I think I have to iterate over all pixels and then check the colors of the pixels infront of the vehicle to make the vehicle bounce in the reflection angle. To execute what suggested I plan on doing the following: I was thinking of defining the inner and outer boundaries using color recognition, in this case white and red, and then check for collision. I am wondering if the implementation is possible especially since I have curves in my track.

If that happens to be the case I want to vehicle to bounce of the track but still move forward using the angle of reflection. I am currently working on a race game where I want to define the collision of my vehicle with the outer and inner borders of the track.