larryhastings/vec

A 2D vector class for Python game development.

vec's Issues

Incompatibility with unit libraries

There is an implementation in vec that prevents it from working with unit libraries, like Pint or natu:

import vec
from natu.units import mm

v = vec.Vector2(x=10*mm, y=5*mm)

returns the following error:

raise ValueError(f"'{self.__class__.__name__}': {s}")
ValueError: 'Vector2Metaclass': when x is an object, you must not specify y, r, or theta

The behavior for Pint is the same.
As I understand this is the part of vec that makes it possible to instantiate a vector with a list or alike object.
Is there any workaround for this?

Dot product calculated incorrectly

Should be multiplying the magnitudes instead of adding them:
sqrt(self.r_squared * other.r_squared) * cos(self.theta - other.theta)
instead of:
sqrt(self.r_squared + other.r_squared) * cos(self.theta - other.theta)