Method __call__

flowmap/visualization/drawing/rendering.py:11–15

(
        self,
        xy: Float[Tensor, "point 2"],
    )

@runtime_checkable
class ColorFunction(Protocol):
    def __call__(
        self,
        xy: Float[Tensor, "point 2"],
    ) -> Float[Tensor, "point 4"]:  # RGBA color
        pass


def generate_sample_grid(