def __init__(self, core, polygon_geog, x0, y0):
"""
Initialises an TilingSystem class for a specified subgrid.
Parameters
----------
core : TPSCoreProperty
defines core parameters of the (sub-) grid
polygon_geog : OGRGeometry
geometry defining the extent/outline of the subgrid
x0 : int
lower-left x (right) coordinates of the subgrid
y0 : int
lower-left y (up) coordinates of the subgrid
"""
self.core = core
self.x0 = x0
self.y0 = y0
self.xstep = self.core.tile_xsize_m
self.ystep = self.core.tile_ysize_m
self.polygon_proj = ptpgeometry.transform_geometry(
polygon_geog, self.core.projection.osr_spref)
self.bbox_proj = ptpgeometry.get_geometry_envelope(
self.polygon_proj, rounding=self.core.sampling)
def __init__(self, core, polygon_geog, tilingsystem=None):
"""
Initialises a TiledProjection().
Parameters
----------
core : TPSCoreProperty
defines core parameters of the (sub-) grid
polygon_geog : OGRGeometry
geometry defining the extent/outline of the subgrid.
if not given, a single global subgrid is assigned to the grid.
tilingsystem : TilingSystem
optional; an instance of TilingSystem()
if not given, a single global tile is assigned to the grid.
"""
self.core = core
self.polygon_geog = ptpgeometry.segmentize_geometry(polygon_geog,
segment=0.5)
self.polygon_proj = ptpgeometry.transform_geometry(
self.polygon_geog, self.core.projection.osr_spref)
self.bbox_proj = ptpgeometry.get_geometry_envelope(
self.polygon_proj, rounding=self.core.sampling)
# does this use anybody? its justs makes problems with the antimeridian!
# self.bbox_geog = ptpgeometry.get_geometry_envelope(
# self.polygon_geog, rounding=self.core.sampling / 1000000.0)
if tilingsystem is None:
tilingsystem = GlobalTile(self.core, 'TG', self.get_bbox_proj())
self.tilesys = tilingsystem
def get_extent_geometry_geog(self):
"""
returns the extent-geometry of the tile in the lon-lat-space.
Returns
-------
OGRGeometry
"""
tile_geom = self.polygon_proj
geo_sr = ptpgeometry.get_geog_spatial_ref()
return ptpgeometry.transform_geometry(tile_geom, geo_sr, segment=25000)
def search_tiles_over_geometry(self, geometry, coverland=True):
"""
Search tiles of the subgrid that are overlapping with the geometry.
Parameters
----------
geometry : OGRGeometry
A point or polygon geometry representing the region of interest.
coverland : Boolean
option to search for tiles covering land at any point in the tile
Returns
-------
overlapped_tiles : list
Return a list of the overlapped tiles' name.
If not found, return empty list.
"""
overlapped_tiles = list()
if geometry.GetGeometryName() in ['MULTIPOINT', 'POINT']:
if geometry.Intersects(self.polygon_geog):
# get intersect area with subgrid in latlon
intersect_geometry = geometry.Intersection(self.polygon_geog)
intersect_geometry = ptpgeometry.transform_geometry(
intersect_geometry, self.projection.osr_spref)
else:
return overlapped_tiles
if geometry.GetGeometryName() in ['POLYGON', 'MULTIPOLYGON']:
# get intersect area with subgrid in latlon
intersect = ptpgeometry.get_lonlat_intersection(
geometry, self.polygon_geog)
# check if geom intersects subgrid
if intersect.Area() == 0.0:
return overlapped_tiles
# transform intersection geometry back to the spatial ref system of the subgrid.
# segmentise for high precision during reprojection.
projected = intersect.GetSpatialReference().IsProjected()
if projected == 0:
max_segment = 0.5
elif projected == 1:
max_segment = 50000
else:
raise Warning(
'Please check unit of geometry before reprojection!')
intersect_geometry = ptpgeometry.transform_geometry(
intersect, self.projection.osr_spref, segment=max_segment)
# get envelope of the geometry
envelope = ptpgeometry.get_geometry_envelope(intersect_geometry)
# get overlapped tiles
tiles = self.tilesys.identify_tiles_overlapping_xybbox(envelope)
for tile in tiles:
# get tile object
t = self.tilesys.create_tile(tile)
# get only tile that overlaps with intersect_geometry
if t.polygon_proj.Intersects(intersect_geometry):
# get only tile if coverland is satisfied
if not coverland or self.tilesys.check_tile_covers_land(
t.name):
overlapped_tiles.append(t.name)
return overlapped_tiles
def _search_tiles_in_roi(self,
roi_geometry=None,
subgrid_ids=None,
coverland=False):
"""
Internal function: Search the tiles of the grid which intersect by the given area.
Parameters
----------
roi_geometry : geometry
a polygon or multipolygon geometry object representing the ROI
sgrid_ids : string or list of strings
subgrid IDs, e.g. specifying over which continent
you want to search.
Default value is None for searching all subgrids.
coverland : Boolean
option to search for tiles covering land at any point in the tile
Returns
-------
list
return a list of the overlapped tiles' name.
If not found, return empty list.
"""
# load lat-lon spatial reference as the default
geog_sr = TPSProjection(epsg=4326).osr_spref
geom_sr = roi_geometry.GetSpatialReference()
if geom_sr is None:
roi_geometry.AssignSpatialReference(geog_sr)
elif not geom_sr.IsSame(geog_sr):
projected = roi_geometry.GetSpatialReference().IsProjected()
if projected == 0:
max_segment = 0.5
elif projected == 1:
max_segment = 50000
else:
raise Warning(
'Please check unit of geometry before reprojection!')
roi_geometry = ptpgeometry.transform_geometry(roi_geometry,
geog_sr,
segment=max_segment)
if roi_geometry.GetGeometryName() == 'MULTIPOLYGON':
roi_polygons = []
for i in range(roi_geometry.GetGeometryCount()):
poly = roi_geometry.GetGeometryRef(i).Clone()
poly.AssignSpatialReference(geog_sr)
roi_polygons.append(poly)
else:
roi_polygons = [roi_geometry]
overlapped_tiles = list()
for roi_polygon in roi_polygons:
# intersect the given grid ids and the overlapped ids
overlapped_grids = self.locate_geometry_in_subgrids(roi_polygon)
subgrid_ids = list(set(subgrid_ids) & set(overlapped_grids))
# finding tiles
for sgrid_id in subgrid_ids:
overlapped_tiles.extend(
self.subgrids[sgrid_id].search_tiles_over_geometry(
roi_polygon, coverland=coverland))
return list(set(overlapped_tiles))
def search_tiles_in_geometry(self, geom, coverland=True):
"""
Search the tiles which are overlapping with the subgrid
Parameters
----------
geom : OGRGeometry
A polygon geometry representing the region of interest.
coverland : Boolean
option to search for tiles covering land at any point in the tile
Returns
-------
overlapped_tiles : list
Return a list of the overlapped tiles' name.
If not found, return empty list.
"""
overlapped_tiles = list()
# check if geom intersects subgrid
if geom.Intersects(self.polygon_geog):
# get intersect area with subgrid in latlon
intersect = geom.Intersection(self.polygon_geog)
else:
return overlapped_tiles
# get spatial reference of subgrid in grid projection
grid_sr = self.projection.osr_spref
# transform intersection geometry back to the spatial reference system
# of the subgrid.
# segmentise for high precision during reprojection.
projected = intersect.GetSpatialReference().IsProjected()
if projected == 0:
max_segment = 0.5
else:
raise Warning('Please check unit of geometry before reprojection!')
intersect = geometry.transform_geometry(intersect, grid_sr,
segment=max_segment)
# get envelope of the Geometry and cal the bounding tile of the
envelope = intersect.GetEnvelope()
lon_min = int(envelope[0]) // self.core.tile_xsize_m \
* self.core.tile_xsize_m
lon_max = (int(envelope[1]) // self.core.tile_xsize_m + 1) \
* self.core.tile_xsize_m
lat_min = int(envelope[2]) // self.core.tile_ysize_m * \
self.core.tile_ysize_m
lat_max = (int(envelope[3]) // self.core.tile_ysize_m + 1) * \
self.core.tile_ysize_m
# get overlapped tiles
lonr = np.arange(
lon_min, lon_max + self.core.tile_xsize_m, self.core.tile_xsize_m)
latr = np.arange(
lat_min, lat_max + self.core.tile_ysize_m, self.core.tile_ysize_m)
for lon, lat in itertools.product(lonr, latr):
geom_tile = geometry.extent2polygon(
(lon, lat, lon + self.core.tile_xsize_m,
lat + self.core.tile_xsize_m), grid_sr)
if geom_tile.Intersects(intersect):
ftile = self.tilesys.point2tilename(lon, lat)
if not coverland or self.tilesys.check_tile_covers_land(ftile):
overlapped_tiles.append(ftile)
return overlapped_tiles