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c++aabb

Horizontal Collision not working AABB C++

Update

Changed the collision code again and made a Component for AABB, now it seems that the problem is only on Horizontal collision, it doesn't push the object enought it think but is the same code as Y axis so it shouldn't be a problem.

(It do detects the horizontal Collision the resolution is the problem)

image

void Hermes_Player::Collision(GameObject * other)
{
    if (other->GetTag() == "wall") {
        AABB* myAABB = dynamic_cast<AABB*>(this->GetComponent("aabb"));
        AABB* otherAABB = dynamic_cast<AABB*>(other->GetComponent("aabb"));
        if (abs(myAABB->lastCenter.x - otherAABB->lastCenter.x) < myAABB->halfCenter.x + otherAABB->halfCenter.x) {
            std::cout << "y" << std::endl;
            if (myAABB->center.y < otherAABB->center.y) {
                int distance = (myAABB->halfCenter.y + otherAABB->halfCenter.y) - (otherAABB->center.y - myAABB->center.y);
                this->Position.y -= distance;
                myAABB->center.y = (myAABB->center.y - distance);
            }
            if (myAABB->center.y > otherAABB->center.y) {
                int distance = (myAABB->halfCenter.y + otherAABB->halfCenter.y) - (myAABB->center.y - otherAABB->center.y);
                this->Position.y += distance;
                myAABB->center.y = (myAABB->center.y + distance);
            }
        }
        else
        {
            std::cout << "x" << std::endl;

            int dist = myAABB->halfCenter.x + otherAABB->halfCenter.x;
            int dif = (this->Size.x + other->Size.x) /2- abs(dist);
            if (myAABB->center.x < otherAABB->center.x) {
                int distance = (myAABB->halfCenter.x + otherAABB->halfCenter.x) - (otherAABB->center.x - myAABB->center.x);
                this->Position.x -= distance;
                myAABB->center.x = (myAABB->center.x - distance);
            }
            if (myAABB->center.x > otherAABB->center.x) {
                int distance = (myAABB->halfCenter.x + otherAABB->halfCenter.x) - (myAABB->center.x - otherAABB->center.x);
                this->Position.x += distance;
                myAABB->center.x = (myAABB->center.x + distance);
            }
            std::cout << this->Position.x << std::endl;
        }
    }
}
Solution

  • This might not be what you are looking for but trying to resolve both the X and Y axis at the same time can be rather complicated.

    One solution might be to step each axis independently and resolve their collisions separately.

    You have to perform collision detection twice but it makes resolution much simpler, IE instead of checking whether the collision resolution results in more collisions you just stop the movement along the edge of the first object collided with.

    This is an article which assisted me when I was developing my own 2D platformer and it recommends this practice:

    http://higherorderfun.com/blog/2012/05/20/the-guide-to-implementing-2d-platformers/