Math

Mutable and immutable vectors, and which one you were handed.

Types#

Math types such as Vector2, Matrix3, and Aabb2 come from Ignis' companion ivector_math package.

ivector_math is a reimplementation of a subset of vector_math in which the mutability of an object is explicitly documented by its type.

Warning

Ignis exports ivector_math. Do not add it to your dependencies.

Mutability#

Each type in ivector_math is immutable by default, but an additional mutable implementation is available with an M prefix. For example, Vector2 is immutable, while MVector2 is mutable and implements Vector2.

final position = Vector2(1, 2);
position.x = 3; // Compile-time error: `x` is final.

final velocity = MVector2(1, 2);
velocity.x = 3; // Sets x to 3.

Since the mutable type always implements the immutable type, you may use the prefix-free version throughout your code by default. When mutation is required, that requirement will now be documented explicitly through a type signature.

The library stays as close as practical to the original vector_math API, with a small number of additions and adjustments to support the immutable/mutable split.