Helpful tools

Assignment 3

Collision System (24/30)

In the past few classes I have attemped to demonstrate what the System part of ECS looks like. There are many Systems we could build but for this project let's just do a simple Collision System.

Build two new classes CollisionComponent and CollisionSystem. The CollisionComponent contains data regarding the type of collision object is being used (sphere, AABB, plane, ...). The ComponentSystem will be tasked with job of doing the math behind collisions.

Let's just do a simple collision. Just in case your forgot how to do the collision response let's just bounce off each other. void CollisionSystem::SphereSphereCollisionResponse(Sphere s1, Ref<PhysicsComponent> pc1, Sphere s2, Ref<PhysicsComponent> pc2) { float e = 1.0f; /// coefficient of restitution Vec3 L = s1.center - s2.center; Vec3 n = VMath::normalize(L); Vec3 v1 = pc1->vel; Vec3 v2 = pc2->vel; float m1 = pc1->mass; float m2 = pc2->mass; float v1p = VMath::dot(v1, n); float v2p = VMath::dot(v2, n); if(v1p - v2p > 0.0f) { /// The colliding objects are not yet free from one and another, come back next cycle return; } float v1p_new = (((m1 - e * m2) * v1p) + ((1.0f + e) * m2 * v2p)) / (m1 + m2); float v2p_new = (((m2 - e * m1) * v2p) + ((1.0f + e) * m1 * v1p)) / (m1 + m2); pc1->vel = v1 + (v1p_new - v1p) * n; pc2->vel = v2 + (v2p_new - v2p) * n; }

Extra: Create the code to automatically to build an AABB around an Object.