# Author: Thomas Moreau <thomas.moreau.2010@gmail.com>
# Author: Olivier Grisel <olivier.grisel@ensta.fr>
# See quad_tree.pyx for details.
cimport numpy as cnp
from ..utils._typedefs cimport float32_t, intp_t
# This is effectively an ifdef statement in Cython
# It allows us to write printf debugging lines
# and remove them at compile time
cdef enum:
DEBUGFLAG = 0
cdef float EPSILON = 1e-6
# XXX: Careful to not change the order of the arguments. It is important to
# have is_leaf and max_width consecutive as it permits to avoid padding by
# the compiler and keep the size coherent for both C and numpy data structures.
cdef struct Cell:
# Base storage structure for cells in a QuadTree object
# Tree structure
intp_t parent # Parent cell of this cell
intp_t[8] children # Array pointing to children of this cell
# Cell description
intp_t cell_id # Id of the cell in the cells array in the Tree
intp_t point_index # Index of the point at this cell (only defined
# # in non empty leaf)
bint is_leaf # Does this cell have children?
float32_t squared_max_width # Squared value of the maximum width w
intp_t depth # Depth of the cell in the tree
intp_t cumulative_size # Number of points included in the subtree with
# # this cell as a root.
# Internal constants
float32_t[3] center # Store the center for quick split of cells
float32_t[3] barycenter # Keep track of the center of mass of the cell
# Cell boundaries
float32_t[3] min_bounds # Inferior boundaries of this cell (inclusive)
float32_t[3] max_bounds # Superior boundaries of this cell (exclusive)
cdef class _QuadTree:
# The QuadTree object is a quad tree structure constructed by inserting
# recursively points in the tree and splitting cells in 4 so that each
# leaf cell contains at most one point.
# This structure also handle 3D data, inserted in trees with 8 children
# for each node.
# Parameters of the tree
cdef public int n_dimensions # Number of dimensions in X
cdef public int verbose # Verbosity of the output
cdef intp_t n_cells_per_cell # Number of children per node. (2 ** n_dimension)
# Tree inner structure
cdef public intp_t max_depth # Max depth of the tree
cdef public intp_t cell_count # Counter for node IDs
cdef public intp_t capacity # Capacity of tree, in terms of nodes
cdef public intp_t n_points # Total number of points
cdef Cell* cells # Array of nodes
# Point insertion methods
cdef int insert_point(self, float32_t[3] point, intp_t point_index,
intp_t cell_id=*) except -1 nogil
cdef intp_t _insert_point_in_new_child(self, float32_t[3] point, Cell* cell,
intp_t point_index, intp_t size=*
) noexcept nogil
cdef intp_t _select_child(self, float32_t[3] point, Cell* cell) noexcept nogil
cdef bint _is_duplicate(self, float32_t[3] point1, float32_t[3] point2) noexcept nogil
# Create a summary of the Tree compare to a query point
cdef long summarize(self, float32_t[3] point, float32_t* results,
float squared_theta=*, intp_t cell_id=*, long idx=*
) noexcept nogil
# Internal cell initialization methods
cdef void _init_cell(self, Cell* cell, intp_t parent, intp_t depth) noexcept nogil
cdef void _init_root(self, float32_t[3] min_bounds, float32_t[3] max_bounds
) noexcept nogil
# Private methods
cdef int _check_point_in_cell(self, float32_t[3] point, Cell* cell
) except -1 nogil
# Private array manipulation to manage the ``cells`` array
cdef int _resize(self, intp_t capacity) except -1 nogil
cdef int _resize_c(self, intp_t capacity=*) except -1 nogil
cdef int _get_cell(self, float32_t[3] point, intp_t cell_id=*) except -1 nogil
cdef Cell[:] _get_cell_ndarray(self)