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SpatialCrosses

Updated
globalmapper.SpatialCrosses(GM_LayerHandle_t32 aLayer1, GM_LayerHandle_t32 aLayer2, GM_SpatialOps_Params_t aParams) → GM_Error_t32

The Crosses predicate returns the area features in aLayer1 that overlap with line features in aLayer2. Note that as opposed to SpatialOverlaps this is an operation between lines and area features. Passing in two layers of area features will return nothing.

Parameters:

  • aLayer1 (GM_LayerHandle_t32) – Input layer with area features

  • aLayer2 (GM_LayerHandle_t32) – Input layer with line features

  • aParams (GM_SpatialOps_Params_t) – Parameters

Returns:

Error Code

Return type:

GM_Error_t32


BEFORE

AFTER
../_images/CrossesBefore.png ../_images/BlueCircle.png

Example

The following is an example of SpatialCrosses.

import os
import globalmapper as gm

import_dir = "Z:/GM-20069/spatial_operations_sample_data/"
# Close all layers that may be open
layers_are_open = gm.GetLoadedLayerList()
if layers_are_open:
    arr_ptr, arr_size = layers_are_open
    initial_layers = gm.GM_LayerHandle_array_frompointer(arr_ptr)
    for i in range(arr_size):
        gm.CloseLayer(initial_layers[i])

err_LoadLayerList1, array_pointer, array_size_param = gm.LoadLayerList(
    os.path.join(import_dir, "LeftBlueCircle.shp"),
    gm.GM_LoadFlags_HideAllPrompts,
)
err_LoadLayerList2, array_pointer, array_size_param = gm.LoadLayerList(
    os.path.join(import_dir, "line.shp"),
    gm.GM_LoadFlags_HideAllPrompts,
)

# Get handle for the loaded layers
arr_ptr, arr_size = gm.GetLoadedLayerList()
layers_array = gm.GM_LayerHandle_array_frompointer(arr_ptr)
layers_list = gm.carray_to_list(layers_array, arr_size)

### START SAMPLE
spatial_params = gm.GM_SpatialOps_Params_t()
spatial_params.mPredicateResultTarget = gm.GM_PredicateResult_CreateNewLayer
spatial_params.mResultLayerName = "Crosses_Result"
err_SpatialCrosses = gm.SpatialCrosses(
    layers_list[0], layers_list[1], spatial_params
)

### END SAMPLE

assert (
    gm.GM_Error_None == err_LoadLayerList1
), f"LoadLayerList1: Expected {gm.GM_Error_None}, got {err_LoadLayerList1}"
assert (
    gm.GM_Error_None == err_LoadLayerList2
), f"LoadLayerList2: Expected {gm.GM_Error_None}, got {err_LoadLayerList2}"
assert (
    gm.GM_Error_None == err_SpatialCrosses
), f"SpatialCrosses: Expected {gm.GM_Error_None}, got {err_SpatialCrosses}"

assert os.path.isdir(import_dir), f"Import directory doesn't exist: {import_dir}"
assert os.path.exists(
    os.path.join(import_dir, "LeftBlueCircle.shp")
), "Sample data doesn't exist"
assert os.path.exists(
    os.path.join(import_dir, "line.shp")
), "Sample data doesn't exist"

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