gaphas.matrix - Gaphas

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# Source code for gaphas.matrix

    """Some Gaphor specific updates to the canvas. This is done by setting the
    correct properties on gaphas' modules.

    Matrix
    ------
    Small utility class wrapping cairo.Matrix. The `Matrix` class adds
    state notification capabilities.
    """

    from __future__ import annotations

    from typing import Callable, SupportsFloat

    import cairo

    Matrixtuple = tuple[float, float, float, float, float, float]

    class Matrix:
        """Matrix wrapper.

        >>> Matrix()
        Matrix(1.0, 0.0, 0.0, 1.0, 0.0, 0.0)
        """

        def __init__(
            self,
            xx: float = 1.0,
            yx: float = 0.0,
            xy: float = 0.0,
            yy: float = 1.0,
            x0: float = 0.0,
            y0: float = 0.0,
            matrix: cairo.Matrix | None = None,
        ) -> None:
            self._matrix = matrix or cairo.Matrix(xx, yx, xy, yy, x0, y0)
            self._handlers: set[Callable[[Matrix, Matrixtuple], None]] = set()

        def add_handler(
            self,
            handler: Callable[[Matrix, Matrixtuple], None],
        ) -> None:
            self._handlers.add(handler)

        def remove_handler(
            self,
            handler: Callable[[Matrix, Matrixtuple], None],
        ) -> None:
            self._handlers.discard(handler)

        def notify(self, old: Matrixtuple) -> None:
            for handler in self._handlers:
                handler(self, old)

        def invert(self) -> None:
            old: Matrixtuple = self.tuple()
            self._matrix.invert()
            self.notify(old)

        def rotate(self, radians: float) -> None:
            old: Matrixtuple = self.tuple()
            self._matrix.rotate(radians)
            self.notify(old)

        def scale(self, sx: float, sy: float) -> None:
            old = self.tuple()
            self._matrix.scale(sx, sy)
            self.notify(old)

        def translate(self, tx: float, ty: float) -> None:
            old: Matrixtuple = self.tuple()
            self._matrix.translate(tx, ty)
            self.notify(old)

        def set(
            self,
            xx: float | None = None,
            yx: float | None = None,
            xy: float | None = None,
            yy: float | None = None,
            x0: float | None = None,
            y0: float | None = None,
        ) -> None:
            updated = False
            m = self._matrix
            old = self.tuple()
            for name, val in (
                ("xx", xx),
                ("yx", yx),
                ("xy", xy),
                ("yy", yy),
                ("x0", x0),
                ("y0", y0),
            ):
                if val is not None and val != getattr(m, name):
                    setattr(m, name, val)
                    updated = True
            if updated:
                self.notify(old)

        def multiply(self, m: Matrix) -> Matrix:
            return Matrix(matrix=self._matrix.multiply(m._matrix))

        def transform_distance(
            self, dx: SupportsFloat, dy: SupportsFloat
        ) -> tuple[float, float]:
            return self._matrix.transform_distance(dx, dy)  # type: ignore[no-any-return]

        def transform_point(
            self, x: SupportsFloat, y: SupportsFloat
        ) -> tuple[float, float]:
            return self._matrix.transform_point(x, y)  # type: ignore[no-any-return]

        def inverse(self) -> Matrix:
            m = Matrix(matrix=cairo.Matrix(*self._matrix))
            m.invert()
            return m

        def tuple(self) -> Matrixtuple:
            return tuple(self)  # type: ignore[arg-type, return-value]

        def to_cairo(self) -> cairo.Matrix:
            return self._matrix

        def __eq__(self, other: object) -> bool:
            # sourcery skip: remove-unnecessary-cast
            return (
                bool(self._matrix == other._matrix) if isinstance(other, Matrix) else False
            )

        def __getitem__(self, val: int) -> float:
            return self._matrix[val]  # type: ignore[no-any-return]

        def __mul__(self, other: Matrix) -> Matrix:
            return Matrix(matrix=self._matrix * other._matrix)

        def __imul__(self, other: Matrix) -> Matrix:
            old: Matrixtuple = self.tuple()
            self._matrix *= other._matrix
            self.notify(old)
            return self

        def __repr__(self) -> str:
            return f"Matrix{tuple(self._matrix)}"