utils.py

# Copyright (c) 2024 Open Navigation LLC
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
 
 
import math
 
from geometry_msgs.msg import Quaternion, Transform
from nav_msgs.msg import OccupancyGrid
import numpy as np
import tf_transformations
 
"""
Transformation utilities for the loopback simulator
"""
 
 
def addYawToQuat(quaternion: Quaternion, yaw_to_add: float) -> Quaternion:
    q = [quaternion.x, quaternion.y, quaternion.z, quaternion.w]
    q2 = tf_transformations.quaternion_from_euler(0.0, 0.0, yaw_to_add)
    q_new = tf_transformations.quaternion_multiply(q, q2)
    new_quaternion = Quaternion()
    new_quaternion.x = q_new[0]
    new_quaternion.y = q_new[1]
    new_quaternion.z = q_new[2]
    new_quaternion.w = q_new[3]
    return new_quaternion
 
 
def transformStampedToMatrix(transform: Transform) -> np.ndarray[np.float64, np.dtype[np.float64]]:
    translation = transform.transform.translation
    rotation = transform.transform.rotation
    matrix = np.eye(4)
    matrix[0, 3] = translation.x
    matrix[1, 3] = translation.y
    matrix[2, 3] = translation.z
    rotation_matrix = tf_transformations.quaternion_matrix([
        rotation.x,
        rotation.y,
        rotation.z,
        rotation.w
    ])
    matrix[:3, :3] = rotation_matrix[:3, :3]
    return matrix
 
 
def matrixToTransform(matrix: np.ndarray[np.float64, np.dtype[np.float64]]) -> Transform:
    transform = Transform()
    transform.translation.x = matrix[0, 3]
    transform.translation.y = matrix[1, 3]
    transform.translation.z = matrix[2, 3]
    quaternion = tf_transformations.quaternion_from_matrix(matrix)
    transform.rotation.x = quaternion[0]
    transform.rotation.y = quaternion[1]
    transform.rotation.z = quaternion[2]
    transform.rotation.w = quaternion[3]
    return transform
 
 
def worldToMap(world_x: float, world_y: float, map_msg: OccupancyGrid) -> tuple[int, int]:
    map_x = int(math.floor((world_x - map_msg.info.origin.position.x) / map_msg.info.resolution))
    map_y = int(math.floor((world_y - map_msg.info.origin.position.y) / map_msg.info.resolution))
    return map_x, map_y
 
 
def getMapOccupancy(x: int, y: int, map_msg: OccupancyGrid):  # type: ignore[no-untyped-def]
    return map_msg.data[y * map_msg.info.width + x]