def IsWithinBBox(points, bbox):
"""Checks if points are within a 2-d bbox.
The function returns true if points are strictly inside the box. It also
returns true when the points are exactly on the box edges.
Args:
points: a float Tensor of shape [..., 2] of points to be tested. The last
coordinates are (x, y).
bbox: a float Tensor of shape [..., 4, 2] of bboxes. The last coordinates
are the four corners of the bbox and (x, y). The corners are assumed to be
given in counter-clockwise order.
Returns:
Tensor: If ``pshape = tf.shape(points)[:-1]`` and
``bshape = tf.shape(bbox)[:-2]``, returns a boolean tensor of shape
``tf.concat(pshape, bshape)``, where each element is true if the point is
inside to the corresponding box. If a point falls exactly on an edge of the
bbox, it is also true.
"""
bshape = py_utils.GetShape(bbox)[:-2]
pshape = py_utils.GetShape(points)[:-1]
bbox = py_utils.HasShape(bbox, tf.concat([bshape, [4, 2]], axis=0))
points = py_utils.HasShape(points, tf.concat([pshape, [2]], axis=0))
# Enumerate all 4 edges:
v1, v2, v3, v4 = (bbox[..., 0, :], bbox[..., 1, :], bbox[...,
2, :], bbox[...,
3, :])
v1v2v3_check = tf.reduce_all(_IsCounterClockwiseDirection(v1, v2, v3))
v2v3v4_check = tf.reduce_all(_IsCounterClockwiseDirection(v2, v3, v4))
v4v1v2_check = tf.reduce_all(_IsCounterClockwiseDirection(v4, v1, v2))
v3v4v1_check = tf.reduce_all(_IsCounterClockwiseDirection(v3, v4, v1))
with tf.control_dependencies([
py_utils.Assert(v1v2v3_check, [v1, v2, v3]),
py_utils.Assert(v2v3v4_check, [v3, v3, v4]),
py_utils.Assert(v4v1v2_check, [v4, v1, v2]),
py_utils.Assert(v3v4v1_check, [v3, v4, v1])
]):
is_inside = tf.math.logical_and(
tf.math.logical_and(_IsOnLeftHandSideOrOn(points, v1, v2),
_IsOnLeftHandSideOrOn(points, v2, v3)),
tf.math.logical_and(_IsOnLeftHandSideOrOn(points, v3, v4),
_IsOnLeftHandSideOrOn(points, v4, v1)))
has_non_zero_area = tf.greater(_BBoxArea(bbox), 0)
is_inside = tf.logical_and(tf.cast(is_inside, tf.bool), has_non_zero_area)
# Swap the last two dimensions.
is_inside = tf.einsum('...ij->...ji', tf.cast(is_inside, tf.int32))
return tf.cast(is_inside, tf.bool)
def IsWithinBBox(points, bbox):
"""Checks if points are within a 2-d bbox.
The function returns true if points are strictly inside the box. It also
returns true when the points are exactly on the box edges.
Args:
points: a float Tensor of shape [..., 2] of points to be tested. The last
coordinates are (x, y).
bbox: a float Tensor of shape [..., 4, 2] of bboxes. The last coordinates
are the four corners of the bbox and (x, y). The corners are assumed to be
given in counter-clockwise order.
Returns:
If pshape = tf.shape(points)[:-1] and bshape = tf.shape(bbox)[:-2],
a tensor of shape tf.concat(pshape, bshape), of booleans, where
each element is true if the point is inside to the corresponding box.
If a point falls exactly on an edge of the bbox, it is also true.
"""
bshape = py_utils.GetShape(bbox)[:-2]
pshape = py_utils.GetShape(points)[:-1]
bbox = py_utils.HasShape(bbox, bshape + [4, 2])
points = py_utils.HasShape(points, pshape + [2])
# Enumerate all 4 edges:
v1, v2, v3, v4 = (bbox[..., 0, :], bbox[..., 1, :], bbox[..., 2, :],
bbox[..., 3, :])
v1v2v3_check = tf.reduce_all(_IsCounterClockwiseDirection(v1, v2, v3))
v2v3v4_check = tf.reduce_all(_IsCounterClockwiseDirection(v2, v3, v4))
v4v1v2_check = tf.reduce_all(_IsCounterClockwiseDirection(v4, v1, v2))
v3v4v1_check = tf.reduce_all(_IsCounterClockwiseDirection(v3, v4, v1))
with tf.control_dependencies([
py_utils.Assert(v1v2v3_check, [v1, v2, v3]),
py_utils.Assert(v2v3v4_check, [v3, v3, v4]),
py_utils.Assert(v4v1v2_check, [v4, v1, v2]),
py_utils.Assert(v3v4v1_check, [v3, v4, v1])
]):
is_inside = tf.logical_and(
tf.logical_and(
_IsOnLeftHandSideOrOn(points, v1, v2),
_IsOnLeftHandSideOrOn(points, v2, v3)),
tf.logical_and(
_IsOnLeftHandSideOrOn(points, v3, v4),
_IsOnLeftHandSideOrOn(points, v4, v1)))
return is_inside