dcs_liberation/tests/flightplan/test_waypointsolver.py
Dan Albert 5cb4c363e3 Build common interface for waypoint geometry constraints.
This is a replacement for the existing "zone geometry" classes that are
currently used for choosing locations for IP, hold, and join points.
The older approach required the author to define the methods for
choosing locations at a rather low level using shapely APIs to merge or
mask geometries. Debug UIs had to be defined manually which was a great
deal of work. Worse, those debug UIs were only useable for *successful*
waypoint placement. If there was a bug in the solver (which was pretty
much unavoidable during development or tuning), it wasn't possible to
use the debug UI.

This new system adds a (very simple) geometric constraint solver to
allow the author to describe the requirements for a waypoint at a high
level. Each waypoint type will define a waypoint solver that defines one
or more waypoint strategies which will be tried in order. For example,
the IP solver might have the following strategies:

1. Safe IP
2. Threat tolerant IP
3. Unsafe IP
4. Safe backtracking IP
5. Unsafe backtracking IP

We prefer those in the order defined, but the preferred strategies won't
always have a valid solution. When that happens, the next one is tried.

The strategies define the constraints for the waypoint location. For
example, the safe IP strategy could be defined as (in pseudo code):

* At least 5 NM away from the departure airfield
* Not farther from the departure airfield than the target is
* Within 10 NM and 45 NM of the target (doctrine dependent)
* Safe
* Within the permissible region, select the point nearest the departure
  airfield

When a solver fails to find a solution using any strategy, debug
information is automatically written in a GeoJSON format which can be
viewed on geojson.io.

Fixes https://github.com/dcs-liberation/dcs_liberation/issues/3085.
2023-08-08 21:46:52 -07:00

232 lines
7.1 KiB
Python

import json
from collections.abc import Iterator
from pathlib import Path
import pytest
from dcs.terrain import Caucasus
from shapely.geometry import Point, MultiPolygon
from shapely.geometry.base import BaseGeometry
from game.flightplan.waypointsolver import WaypointSolver, NoSolutionsError
from game.flightplan.waypointstrategy import WaypointStrategy
class NoSolutionsStrategy(WaypointStrategy):
def __init__(self) -> None:
super().__init__(MultiPolygon([]))
def find(self) -> Point | None:
return None
class PointStrategy(WaypointStrategy):
def __init__(self, x: float, y: float) -> None:
super().__init__(MultiPolygon([]))
self.point = Point(x, y)
def find(self) -> Point | None:
return self.point
class OriginStrategy(PointStrategy):
def __init__(self) -> None:
super().__init__(0, 0)
class DebuggableStrategy(NoSolutionsStrategy):
def __init__(self, distance_factor: int) -> None:
super().__init__()
center = Point(0, 0)
self.exclude("foo", center.buffer(1 * distance_factor))
self.exclude(
"bar",
center.buffer(3 * distance_factor).difference(
center.buffer(2 * distance_factor)
),
)
class SolverWithInputs(WaypointSolver):
def describe_inputs(self) -> Iterator[tuple[str, BaseGeometry]]:
yield "foo", Point(0, 0)
yield "bar", Point(1, 1)
def test_solver_tries_strategies_in_order() -> None:
solver = WaypointSolver()
solver.add_strategy(OriginStrategy())
solver.add_strategy(PointStrategy(1, 1))
assert solver.solve() == Point(0, 0)
def test_individual_failed_strategies_do_not_fail_solver() -> None:
solver = WaypointSolver()
solver.add_strategy(NoSolutionsStrategy())
solver.add_strategy(OriginStrategy())
assert solver.solve() == Point(0, 0)
def test_no_solutions_raises() -> None:
solver = WaypointSolver()
solver.add_strategy(NoSolutionsStrategy())
with pytest.raises(NoSolutionsError):
solver.solve()
def test_no_strategies_raises() -> None:
solver = WaypointSolver()
with pytest.raises(ValueError):
solver.solve()
def test_success_does_not_dump_debug_info(tmp_path: Path) -> None:
solver = WaypointSolver()
solver.set_debug_properties(tmp_path, Caucasus())
solver.add_strategy(OriginStrategy())
solver.solve()
assert not list(tmp_path.iterdir())
def test_no_solutions_dumps_debug_info(tmp_path: Path) -> None:
center = Point(0, 0)
solver = WaypointSolver()
solver.set_debug_properties(tmp_path, Caucasus())
strategy_0 = DebuggableStrategy(distance_factor=1)
strategy_1 = DebuggableStrategy(distance_factor=2)
strategy_1.prerequisite(center).is_safe()
solver.add_strategy(strategy_0)
solver.add_strategy(strategy_1)
with pytest.raises(NoSolutionsError):
solver.solve()
strategy_0_path = tmp_path / "0.json"
strategy_1_path = tmp_path / "1.json"
assert set(tmp_path.iterdir()) == {
tmp_path / "solver.json",
strategy_0_path,
strategy_1_path,
}
with strategy_0_path.open("r", encoding="utf-8") as metadata_file:
data = json.load(metadata_file)
assert data["type"] == "FeatureCollection"
assert data["metadata"]["name"] == "DebuggableStrategy"
assert data["metadata"]["prerequisites"] == []
assert len(data.keys()) == 3
features = data["features"]
assert len(features) == 2
for debug_info, feature in zip(strategy_0.iter_debug_info(), features):
assert debug_info.to_geojson(solver.to_geojson) == feature
with strategy_1_path.open("r", encoding="utf-8") as metadata_file:
data = json.load(metadata_file)
assert data["type"] == "FeatureCollection"
assert data["metadata"]["name"] == "DebuggableStrategy"
assert data["metadata"]["prerequisites"] == [
{
"requirement": "is safe",
"satisfied": True,
"subject": solver.to_geojson(center),
}
]
assert len(data.keys()) == 3
features = data["features"]
assert len(features) == 2
for debug_info, feature in zip(strategy_1.iter_debug_info(), features):
assert debug_info.to_geojson(solver.to_geojson) == feature
def test_no_solutions_dumps_inputs(tmp_path: Path) -> None:
solver = SolverWithInputs()
solver.set_debug_properties(tmp_path, Caucasus())
solver.add_strategy(NoSolutionsStrategy())
with pytest.raises(NoSolutionsError):
solver.solve()
inputs_path = tmp_path / "solver.json"
with inputs_path.open(encoding="utf-8") as inputs_file:
data = json.load(inputs_file)
assert data == {
"type": "FeatureCollection",
"metadata": {
"name": "SolverWithInputs",
"terrain": "Caucasus",
},
"features": [
{
"type": "Feature",
"properties": {"description": "foo"},
"geometry": {
"type": "Point",
"coordinates": [34.265515188456, 45.129497060328966],
},
},
{
"type": "Feature",
"properties": {"description": "bar"},
"geometry": {
"type": "Point",
"coordinates": [34.265528100962584, 45.1295059189547],
},
},
],
}
def test_solver_inputs_appear_in_strategy_features(tmp_path: Path) -> None:
solver = SolverWithInputs()
solver.set_debug_properties(tmp_path, Caucasus())
solver.add_strategy(PointStrategy(2, 2))
solver.dump_debug_info()
strategy_path = tmp_path / "0.json"
with strategy_path.open(encoding="utf-8") as inputs_file:
data = json.load(inputs_file)
assert data == {
"type": "FeatureCollection",
"metadata": {
"name": "PointStrategy",
"prerequisites": [],
},
"features": [
{
"type": "Feature",
"properties": {"description": "foo"},
"geometry": {
"type": "Point",
"coordinates": [34.265515188456, 45.129497060328966],
},
},
{
"type": "Feature",
"properties": {"description": "bar"},
"geometry": {
"type": "Point",
"coordinates": [34.265528100962584, 45.1295059189547],
},
},
{
"type": "Feature",
"properties": {"description": "solution"},
"geometry": {
"coordinates": [34.265541013473154, 45.12951477757893],
"type": "Point",
},
},
],
}
def test_to_geojson(tmp_path: Path) -> None:
solver = WaypointSolver()
solver.set_debug_properties(tmp_path, Caucasus())
assert solver.to_geojson(Point(0, 0)) == {
"coordinates": [34.265515188456, 45.129497060328966],
"type": "Point",
}
assert solver.to_geojson(MultiPolygon([])) == {
"type": "MultiPolygon",
"coordinates": [],
}