private CollisionInfo AABBvsAABB(AABB_Collider lhs, AABB_Collider rhs)
{
Vec2 lhsPos = new Vec2(lhs.transform.position.x, lhs.transform.position.y) + lhs.LocalOffset;
Vec2 rhsPos = new Vec2(rhs.transform.position.x, rhs.transform.position.y) + rhs.LocalOffset;
Vec2 lhsBottomLeft = lhs.BottomLeft + lhsPos;
Vec2 lhsTopRight = lhs.TopRight + lhsPos;
Vec2 rhsBottomLeft = rhs.BottomLeft + rhsPos;
Vec2 rhsTopRight = rhs.TopRight + rhsPos;
if (lhsBottomLeft.x < rhsTopRight.x &&
lhsTopRight.x > rhsBottomLeft.x &&
lhsTopRight.y > rhsBottomLeft.y &&
lhsBottomLeft.y < rhsTopRight.y)
{
Vec2 vMult = Vec2.One;
Vec2 depth = Vec2.Zero;
Vec2 colNorm = Vec2.Zero;
if (lhsPos.x > rhsPos.x)
{
colNorm.x = -1f;
depth.x = rhsTopRight.x - lhsBottomLeft.x;
}
else
{
colNorm.x = 1f;
depth.x = rhsBottomLeft.x - lhsTopRight.x;
}
if (lhsPos.y > rhsPos.y)
{
colNorm.y = -1f;
depth.y = rhsTopRight.y - lhsBottomLeft.y;
}
else
{
colNorm.y = 1f;
depth.y = rhsBottomLeft.y - lhsTopRight.y;
}
if (Mathf.Abs(depth.x) > Mathf.Abs(depth.y))
{
colNorm.x = 0f;
depth.x = 0f;
vMult.y = 0f;
}
else
{
colNorm.y = 0f;
depth.y = 0f;
vMult.x = 0f;
}
return(new CollisionInfo(true, depth, colNorm));
}
return(new CollisionInfo());
}
private CollisionInfo CIRCLEvsAABB(Circle_Collider lhs, AABB_Collider rhs, bool invertNormal)
{
// Vector from A to B
Vector3 n = lhs.transform.position - rhs.transform.position;
// Closest point on A to center of B
Vector3 closest = n;
// Calculate half extents along each axis
float x_extent = rhs.Width * 0.5f;
float y_extent = rhs.Height * 0.5f;
// Clamp point to edges of the AABB
closest.x = Mathf.Clamp(closest.x, -x_extent, x_extent);
closest.y = Mathf.Clamp(closest.y, -y_extent, y_extent);
bool inside = false;
// Circle is inside the AABB, so we need to clamp the circle's center
// to the closest edge
if (n == closest)
{
inside = true;
// Find closest axis
if (Mathf.Abs(n.x) > Mathf.Abs(n.y))
{
// Clamp to closest extent
if (closest.x > 0)
{
closest.x = x_extent;
}
else
{
closest.x = -x_extent;
}
}
// y axis is shorter
else
{
// Clamp to closest extent
if (closest.y > 0)
{
closest.y = y_extent;
}
else
{
closest.y = -y_extent;
}
}
}
Vector3 normal = n - closest;
float d = normal.sqrMagnitude;
float r = lhs.Radius;
float penetration = 0f;
// Early out if the radius is shorter than distance to closest point and
// Circle not inside the AABB
if (d > r * r && !inside)
{
return(new CollisionInfo());
}
// Avoided sqrt until needed
d = Mathf.Sqrt(d);
// Collision normal needs to be flipped to point outside if circle was
// inside the AABB
if (inside)
{
normal = invertNormal ? -normal : normal;
}
else
{
normal = invertNormal ? normal : -normal;
}
penetration = r - d;
Vec2 depth = new Vec2(normal.x, normal.y).Normalize();
return(new CollisionInfo(true, depth * penetration, depth));
}
