Properly transform coordinates for geotiff contours

pyhgtmap/__init__.py

@@ -1,5 +1,5 @@
 from importlib.metadata import version
-from typing import List, Tuple
+from typing import List, NamedTuple, Tuple
 
 __author__ = "Aurélien Grenotton (agrenott@gmail.com)"
 __version__ = version("pyhgtmap")
@@ -9,4 +9,12 @@
 # Some type aliases
 Polygon = List[Tuple[float, float]]
 PolygonsList = List[Polygon]
-BoudingBox = Tuple[float, float, float, float]
+
+
+class BBox(NamedTuple):
+    """Simple bounding box."""
+
+    min_lon: float
+    min_lat: float
+    max_lon: float
+    max_lat: float

pyhgtmap/hgt/__init__.py

@@ -1,9 +1,8 @@
 from __future__ import annotations
 
-from typing import TYPE_CHECKING, Callable, Iterable, Tuple
+from typing import Callable, Iterable, Tuple
 
-if TYPE_CHECKING:
-    from pyhgtmap import BoudingBox
+from pyhgtmap import BBox
 
 # Coordinates transformation function prototype
 TransformFunType = Callable[
@@ -12,7 +11,7 @@
 ]
 
 
-def makeBBoxString(bbox: BoudingBox) -> str:
+def makeBBoxString(bbox: BBox) -> str:
     return f"{{0:s}}lon{bbox[0]:.2f}_{bbox[2]:.2f}lat{bbox[1]:.2f}_{bbox[3]:.2f}"
 
 
@@ -22,9 +21,9 @@ def transformLonLats(
     maxLon: float,
     maxLat: float,
     transform: TransformFunType | None,
-) -> BoudingBox:
+) -> BBox:
     if transform is None:
-        return minLon, minLat, maxLon, maxLat
+        return BBox(minLon, minLat, maxLon, maxLat)
     else:
         (lon1, lat1), (lon2, lat2), (lon3, lat3), (lon4, lat4) = transform(
             [(minLon, minLat), (maxLon, maxLat), (minLon, maxLat), (maxLon, maxLat)],
@@ -33,4 +32,4 @@ def transformLonLats(
         maxLon = max([lon1, lon2, lon3, lon4])
         minLat = min([lat1, lat2, lat3, lat4])
         maxLat = max([lat1, lat2, lat3, lat4])
-        return minLon, minLat, maxLon, maxLat
+        return BBox(minLon, minLat, maxLon, maxLat)

pyhgtmap/hgt/contour.py

@@ -130,6 +130,8 @@ def trace(self, elevation: int) -> tuple[list[numpy.ndarray], int, int]:
         numOfPaths, numOfNodes = 0, 0
         resultPaths = []
         for path in rawPaths:
+            if self.transform:
+                path = numpy.array(self.transform(path))
             path = simplify_path(path, self.rdp_epsilon)
             splitPaths, numOfNodesAdd, numOfPathsAdd = self.splitList(path)
             resultPaths.extend(splitPaths)

pyhgtmap/hgt/file.py

@@ -12,12 +12,13 @@
 from matplotlib.path import Path as PolygonPath
 from scipy import ndimage
 
+from pyhgtmap import BBox
 from pyhgtmap.hgt import TransformFunType, transformLonLats
 
 from .tile import HgtTile
 
 if TYPE_CHECKING:
-    from pyhgtmap import BoudingBox, Polygon, PolygonsList
+    from pyhgtmap import Polygon, PolygonsList
     from pyhgtmap.cli import Configuration
 
     with suppress(ImportError):
@@ -90,7 +91,7 @@ def parse_hgt_filename(
     filename: str,
     corrx: float,
     corry: float,
-) -> BoudingBox:
+) -> BBox:
     """tries to extract borders from filename and returns them as a tuple
     of floats:
     (<min longitude>, <min latitude>, <max longitude>, <max latitude>)
@@ -123,7 +124,7 @@ def parse_hgt_filename(
             f"something wrong with longitude coding in filename {filename:s}",
         )
     maxLon = minLon + 1
-    return minLon + corrx, minLat + corry, maxLon + corrx, maxLat + corry
+    return BBox(minLon + corrx, minLat + corry, maxLon + corrx, maxLat + corry)
 
 
 def get_transform(
@@ -168,7 +169,7 @@ def parse_geotiff_bbox(
     corrx: float,
     corry: float,
     doTransform: bool,
-) -> BoudingBox:
+) -> BBox:
     try:
         from osgeo import gdal, osr
 
@@ -210,7 +211,7 @@ def parse_geotiff_bbox(
             maxLat,
             transform,
         )
-        return minLon + corrx, minLat + corry, maxLon + corrx, maxLat + corry
+        return BBox(minLon + corrx, minLat + corry, maxLon + corrx, maxLat + corry)
     else:
         # we need to take care for corrx, corry values then, which are always expected
         # to be EPSG:4326, so transform, add corrections, and transform back to
@@ -239,15 +240,15 @@ def parse_geotiff_bbox(
             maxLat,
             reverseTransform,
         )
-        return minLon, minLat, maxLon, maxLat
+        return BBox(minLon, minLat, maxLon, maxLat)
 
 
 def parse_file_for_bbox(
     fullFilename: str,
     corrx: float,
     corry: float,
     doTransform: bool,
-) -> BoudingBox:
+) -> BBox:
     fileExt: str = os.path.splitext(fullFilename)[1].lower().replace(".", "")
     if fileExt == "hgt":
         return parse_hgt_filename(os.path.split(fullFilename)[1], corrx, corry)
@@ -260,15 +261,15 @@ def calc_hgt_area(
     filenames: list[tuple[str, bool]],
     corrx: float,
     corry: float,
-) -> BoudingBox:
+) -> BBox:
     bboxes = [
         parse_file_for_bbox(f[0], corrx, corry, doTransform=True) for f in filenames
     ]
     minLon = sorted([b[0] for b in bboxes])[0]
     minLat = sorted([b[1] for b in bboxes])[0]
     maxLon = sorted([b[2] for b in bboxes])[-1]
     maxLat = sorted([b[3] for b in bboxes])[-1]
-    return minLon, minLat, maxLon, maxLat
+    return BBox(minLon, minLat, maxLon, maxLat)
 
 
 BBOX_EXPAND_EPSILON = 0.1
@@ -544,7 +545,7 @@ def init_as_geotiff(
             else:
                 self.polygons = None
 
-    def borders(self, corrx=0.0, corry=0.0) -> BoudingBox:
+    def borders(self, corrx=0.0, corry=0.0) -> BBox:
         """determines the bounding box of self.filename using parseHgtFilename()."""
         return parse_file_for_bbox(self.fullFilename, corrx, corry, doTransform=False)
 
@@ -558,7 +559,7 @@ def make_tiles(self, opts: Configuration) -> list[HgtTile]:
 
         def truncate_data(
             area: str | None, inputData: numpy.ma.masked_array
-        ) -> tuple[BoudingBox, numpy.ma.masked_array]:
+        ) -> tuple[BBox, numpy.ma.masked_array]:
             """truncates a numpy array.
             returns (<min lon>, <min lat>, <max lon>, <max lat>) and an array of the
             truncated height data.
@@ -628,12 +629,14 @@ def truncate_data(
                     maxLatTruncIndex:minLatTruncIndex,
                     minLonTruncIndex:maxLonTruncIndex,
                 ]
-                return (realMinLon, realMinLat, realMaxLon, realMaxLat), zData
+                return BBox(realMinLon, realMinLat, realMaxLon, realMaxLat), zData
             else:
-                return (self.minLon, self.minLat, self.maxLon, self.maxLat), inputData
+                return BBox(
+                    self.minLon, self.minLat, self.maxLon, self.maxLat
+                ), inputData
 
         def chop_data(
-            inputBbox: BoudingBox,
+            inputBbox: BBox,
             inputData: numpy.ma.masked_array,
             depth=0,
         ):
@@ -666,7 +669,12 @@ def too_many_nodes(data: numpy.ma.masked_array) -> bool:
                     return False
                 return estim_num_of_nodes(data) > maxNodes
 
-            def get_chops(unchoppedData: numpy.ma.masked_array, unchoppedBbox):
+            def get_chops(
+                unchoppedData: numpy.ma.masked_array, unchoppedBbox
+            ) -> tuple[
+                tuple[BBox, numpy.ma.masked_array],
+                tuple[BBox, numpy.ma.masked_array],
+            ]:
                 """returns a data chop and the according bbox. This function is
                 recursively called until all tiles are estimated to be small enough.
 
@@ -684,13 +692,13 @@ def get_chops(unchoppedData: numpy.ma.masked_array, unchoppedBbox):
                 unchoppedNumOfRows = unchoppedData.shape[0]
                 chopLatIndex = int(unchoppedNumOfRows / 2.0)
                 chopLat = unchoppedBboxMaxLat - (chopLatIndex * self.latIncrement)
-                lowerChopBbox = (
+                lowerChopBbox = BBox(
                     unchoppedBboxMinLon,
                     unchoppedBboxMinLat,
                     unchoppedBboxMaxLon,
                     chopLat,
                 )
-                upperChopBbox = (
+                upperChopBbox = BBox(
                     unchoppedBboxMinLon,
                     chopLat,
                     unchoppedBboxMaxLon,

pyhgtmap/hgt/processor.py

@@ -5,7 +5,7 @@
 from multiprocessing.sharedctypes import Synchronized
 from typing import TYPE_CHECKING, Callable, cast
 
-from pyhgtmap import BoudingBox
+from pyhgtmap import BBox
 from pyhgtmap.hgt.file import HgtFile
 from pyhgtmap.output.factory import get_osm_output
 
@@ -68,7 +68,7 @@ def single_output(self) -> bool:
     def get_osm_output(
         self,
         hgt_files_names: list[str],
-        bounding_box: BoudingBox,
+        bounding_box: BBox,
     ) -> Output:
         """Allocate or return already existing OSM output (for consecutive calls in single output mode)
 
@@ -267,7 +267,7 @@ def process_files(self, files: list[tuple[str, bool]]) -> None:
             self.get_osm_output(
                 [file_tuple[0] for file_tuple in files],
                 cast(
-                    BoudingBox,
+                    BBox,
                     [float(b) for b in self.options.area.split(":")],
                 ),
             )

pyhgtmap/hgt/tile.py

@@ -7,11 +7,12 @@
 import numpy
 import numpy.typing
 
+from pyhgtmap import BBox
 from pyhgtmap.hgt import TransformFunType, makeBBoxString, transformLonLats
 from pyhgtmap.hgt.contour import ContoursGenerator, build_contours
 
 if TYPE_CHECKING:
-    from pyhgtmap import BoudingBox, PolygonsList
+    from pyhgtmap import PolygonsList
 
 meters2Feet = 1.0 / 0.3048
 
@@ -32,7 +33,7 @@ class HgtTile:
 
     def __init__(
         self,
-        bbox: BoudingBox,
+        bbox: BBox,
         data: numpy.ma.masked_array,
         increments: tuple[float, float],
         polygons: PolygonsList | None,
@@ -88,7 +89,7 @@ def getElevRange(self) -> tuple[int, int]:
         maxEle = int(self.zData.max())
         return minEle, maxEle
 
-    def bbox(self, doTransform=True) -> BoudingBox:
+    def bbox(self, doTransform=True) -> BBox:
         """returns the bounding box of the current tile."""
         if doTransform:
             return transformLonLats(
@@ -99,7 +100,7 @@ def bbox(self, doTransform=True) -> BoudingBox:
                 self.transform,
             )
         else:
-            return self.minLon, self.minLat, self.maxLon, self.maxLat
+            return BBox(self.minLon, self.minLat, self.maxLon, self.maxLat)
 
     def contourLines(
         self,

pyhgtmap/output/factory.py

@@ -11,12 +11,12 @@
 from . import make_elev_classifier
 
 if TYPE_CHECKING:
-    from pyhgtmap import BoudingBox
+    from pyhgtmap import BBox
     from pyhgtmap.cli import Configuration
 
 
 def make_osm_filename(
-    borders: BoudingBox,
+    borders: BBox,
     opts: Configuration,
     input_files_names: list[str],
 ) -> str:
@@ -81,7 +81,7 @@ def makeBoundsString(bbox: Any) -> str:
 def get_osm_output(
     opts: Configuration,
     input_files_names: list[str],
-    bounds: BoudingBox,
+    bounds: BBox,
 ) -> Output:
     """Return the proper OSM Output generator."""
     outputFilename = make_osm_filename(bounds, opts, input_files_names)

pyhgtmap/output/o5mUtil.py

@@ -9,7 +9,7 @@
 from pyhgtmap.varint import int2str, join, sint2str, writableInt, writableString
 
 if TYPE_CHECKING:
-    from pyhgtmap import BoudingBox
+    from pyhgtmap import BBox
     from pyhgtmap.hgt.tile import TileContours
 
 HUNDREDNANO = 10000000
@@ -42,7 +42,7 @@ def __init__(
         filename,
         osmVersion,
         pyhgtmap_version,
-        bbox: BoudingBox,
+        bbox: BBox,
         elevClassifier: Callable[[int], str],
         writeTimestamp=False,
     ) -> None:

pyhgtmap/output/pbfUtil.py

@@ -15,7 +15,7 @@
 import pyhgtmap.output
 
 if TYPE_CHECKING:
-    from pyhgtmap import BoudingBox
+    from pyhgtmap import BBox
     from pyhgtmap.hgt.tile import TileContours
 
 
@@ -37,7 +37,7 @@ def __init__(
         filename,
         osmVersion,
         pyhgtmap_version,
-        bbox: BoudingBox,
+        bbox: BBox,
         elevClassifier: Callable[[int], str],
     ):
         super().__init__()

tests/hgt/__init__.py

@@ -0,0 +1,24 @@
+import contextlib
+import importlib.util
+from typing import Generator
+
+
+@contextlib.contextmanager
+def handle_optional_geotiff_support() -> Generator[None, None, None]:
+    """
+    Context manager handling the cases where optional GeoTiff support has an impact.
+    Cases should run fully if geotiff dependencies are available, else specific exception is
+    expected.
+    """
+    try:
+        # Execute test case
+        yield
+    except ImportError as ex:
+        if importlib.util.find_spec("osgeo") is not None:
+            # GDAL module is available, do NOT ignore the exception
+            raise
+        # GDAL not available, ensure the proper errror message is raised
+        assert (  # noqa: PT017 # Test is more complex
+            ex.msg
+            == "GeoTiff optional support not enabled; please install with 'pip install pyhgtmap[geotiff]'"
+        )