Merge branch 'main' into 42-add-a-way-to-create-a-new-qgis-line-layer…

…-which-can-be-used-as-a-gate-layer

fvh3t/core/exceptions.py

@@ -19,3 +19,7 @@ class InvalidTrajectoryException(QgsPluginException):
 
 class InvalidFeatureException(QgsPluginException):
     pass
+
+
+class InvalidSegmentException(QgsPluginException):
+    pass

fvh3t/core/trajectory_segment.py

@@ -2,9 +2,19 @@
 
 from typing import TYPE_CHECKING
 
-from qgis.core import QgsGeometry
+from qgis.core import (
+    QgsCoordinateReferenceSystem,
+    QgsCoordinateTransformContext,
+    QgsDistanceArea,
+    QgsGeometry,
+    QgsUnitTypes,
+)
+
+from fvh3t.core.exceptions import InvalidSegmentException
 
 if TYPE_CHECKING:
+    from datetime import timedelta
+
     from fvh3t.core.gate import Gate
     from fvh3t.core.trajectory import TrajectoryNode
 
@@ -19,6 +29,30 @@ def __init__(self, node_a: TrajectoryNode, node_b: TrajectoryNode) -> None:
         self.node_a = node_a
         self.node_b = node_b
 
+    def speed(self, crs: QgsCoordinateReferenceSystem) -> float:
+        da = QgsDistanceArea()
+        da.setSourceCrs(crs, QgsCoordinateTransformContext())
+
+        convert: bool = da.lengthUnits() != QgsUnitTypes.DistanceUnit.DistanceMeters
+
+        distance_m: float = da.measureLine(self.node_b.point, self.node_a.point)
+        if convert:
+            distance_m = da.convertLengthMeasurement(distance_m, QgsUnitTypes.DistanceUnit.DistanceMeters)
+
+        time_difference: timedelta = self.node_b.timestamp - self.node_a.timestamp
+        seconds: float = distance_m / time_difference.total_seconds()
+
+        if seconds > 0:
+            meters_per_second = distance_m / seconds
+
+            return round(meters_per_second * 3.6, 2)
+
+        if seconds < 0:
+            msg = "Node A must be earlier than node B, timewise!"
+            raise InvalidSegmentException(msg)
+
+        return 0.0
+
     def as_geometry(self) -> QgsGeometry:
         return QgsGeometry.fromPolylineXY([self.node_a.point, self.node_b.point])
 

tests/core/test_trajectory_segment.py

@@ -1,5 +1,7 @@
 from typing import TYPE_CHECKING
 
+from qgis.core import QgsCoordinateReferenceSystem
+
 if TYPE_CHECKING:
     from fvh3t.core.trajectory_segment import TrajectorySegment
 
@@ -42,3 +44,7 @@ def test_trajectory_as_segments(two_node_trajectory, three_node_trajectory):
 
 def test_trajectory_segment_as_geometry(trajectory_segment):
     assert trajectory_segment.as_geometry().asWkt() == "LineString (0 0, 0 1)"
+
+
+def test_trajectory_segment_speed(trajectory_segment):
+    assert trajectory_segment.speed(QgsCoordinateReferenceSystem("EPSG:3067")) == 3.6