Exemple #1
0
def calc_surrounding_area(zone_gdf, buffer_m):
    geometry_without_holes = zone_gdf.convex_hull
    geometry_without_holes_gdf = Gdf(geometry=geometry_without_holes.values)
    geometry_without_holes_gdf["one_class"] = "buildings"
    geometry_merged = geometry_without_holes_gdf.dissolve(by='one_class',
                                                          aggfunc='sum')
    geometry_merged_final = Gdf(geometry=geometry_merged.convex_hull)
    new_buffer = Gdf(geometry=geometry_merged_final.buffer(buffer_m))
    area = overlay(geometry_merged_final,
                   new_buffer,
                   how='symmetric_difference')

    # THIS IS ANOTHER METHOD, NOT FUNCTIONAL THOUGH
    # from shapely.ops import Point
    # # new GeoDataFrame with same columns
    # points = []
    # # Extraction of the polygon nodes and attributes values from polys and integration into the new GeoDataFrame
    # for index, row in zone_gdf.iterrows():
    #     for j in list(row['geometry'].exterior.coords):
    #         points.append(Point(j))
    #
    # concave_hull, edge_points = alpha_shape(points, alpha=0.1)
    # simple_polygons = [x for x in concave_hull]
    # geometry_merged_final = Gdf(geometry=simple_polygons)
    # geometry_merged_final.plot()
    # plt.show()
    # new_buffer = Gdf(geometry=geometry_merged_final.buffer(buffer_m))
    # area = overlay(geometry_merged_final, new_buffer, how='symmetric_difference')
    # area.plot()

    return area, geometry_merged_final
Exemple #2
0
def calc_raster_terrain_fixed_elevation(crs, elevation, grid_size, raster_path,
                                        locator, x_max, x_min, y_max, y_min):
    # local variables:
    temp_shapefile = locator.get_temporary_file("terrain.shp")
    cols = int((x_max - x_min) / grid_size)
    rows = int((y_max - y_min) / grid_size)
    shapes = Polygon([[x_min, y_min], [x_max, y_min], [x_max, y_max],
                      [x_min, y_max], [x_min, y_min]])
    geodataframe = Gdf(index=[0], crs=crs, geometry=[shapes])
    geodataframe.to_file(temp_shapefile)
    # 1) opening the shapefile
    source_ds = ogr.Open(temp_shapefile)
    source_layer = source_ds.GetLayer()
    target_ds = gdal.GetDriverByName('GTiff').Create(
        raster_path, cols, rows, 1, gdal.GDT_Float32)  ##COMMENT 2
    target_ds.SetGeoTransform(
        (x_min, grid_size, 0, y_max, 0, -grid_size))  ##COMMENT 3
    # 5) Adding a spatial reference ##COMMENT 4
    target_dsSRS = osr.SpatialReference()
    target_dsSRS.ImportFromProj4(crs)
    target_ds.SetProjection(target_dsSRS.ExportToWkt())
    band = target_ds.GetRasterBand(1)
    band.SetNoDataValue(-9999)  ##COMMENT 5
    gdal.RasterizeLayer(target_ds, [1], source_layer,
                        burn_values=[elevation])  ##COMMENT 6
    target_ds = None  # closing the file