bonk-docs/content/api/IShape2D.md

title	date	weight
IShape2D	2019-09-15T11:06:50-07:00	5

An IShape2D is an interface that, when implemented, allows for spatial hashing and the computation of Minkowski Differences.

Your IShape2D implementations should be structs for memory efficiency purposes.

Properties

public AABB { get; }

An axis-aligned bounding box for the shape. This is stored so we can efficiently transform the AABB when necessary.

Methods

Vector2 Support(Vector2 direction, Transform2D transform)

A method which implements a support function for use with a Minkowski Difference.

The support function must, given a directional vector and a Transform2D, return the farthest possible vertex of the transformed shape in the given direction.

For example, the support function for Bonk's Circle implementation:

public Vector2 Support(Vector2 direction, Transform2D transform)
{
    return Vector2.Transform(Vector2.Normalize(direction) * Radius, transform.TransformMatrix);
}

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AABB TransformedAABB(Transform2D transform)

A method which returns the axis-aligned bounding box for the transformed shape.

For example, the AABB method for Bonk's Circle implementation:

public AABB TransformedAABB(Transform2D Transform2D)
{
    return AABB.Transformed(AABB, transform2D);
}