scikit-image

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from ._pnpoly import _grid_points_in_poly, _points_in_poly
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def grid_points_in_poly(shape, verts, binarize=True):
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    """Test whether points on a specified grid are inside a polygon.
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    For each ``(r, c)`` coordinate on a grid, i.e. ``(0, 0)``, ``(0, 1)`` etc.,
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    test whether that point lies inside a polygon.
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    You can control the output type with the `binarize` flag. Please refer to its
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    documentation for further details.
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    Parameters
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    ----------
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    shape : tuple (M, N)
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        Shape of the grid.
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    verts : (V, 2) array
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        Specify the V vertices of the polygon, sorted either clockwise
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        or anti-clockwise. The first point may (but does not need to be)
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        duplicated.
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    binarize: bool
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        If `True`, the output of the function is a boolean mask.
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        Otherwise, it is a labeled array. The labels are:
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        O - outside, 1 - inside, 2 - vertex, 3 - edge.
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    See Also
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    --------
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    points_in_poly
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    Returns
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    -------
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    mask : (M, N) ndarray
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        If `binarize` is True, the output is a boolean mask. True means the
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        corresponding pixel falls inside the polygon.
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        If `binarize` is False, the output is a labeled array, with pixels
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        having a label between 0 and 3. The meaning of the values is:
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        O - outside, 1 - inside, 2 - vertex, 3 - edge.
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    """
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    output = _grid_points_in_poly(shape, verts)
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    if binarize:
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        output = output.astype(bool)
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    return output
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def points_in_poly(points, verts):
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    """Test whether points lie inside a polygon.
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    Parameters
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    ----------
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    points : (K, 2) array
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        Input points, ``(x, y)``.
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    verts : (L, 2) array
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        Vertices of the polygon, sorted either clockwise or anti-clockwise.
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        The first point may (but does not need to be) duplicated.
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    See Also
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    --------
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    grid_points_in_poly
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    Returns
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    -------
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    mask : (K,) array of bool
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        True if corresponding point is inside the polygon.
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    """
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    return _points_in_poly(points, verts)
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