Skip to main content

SpatialWithin

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

The Within predicate returns the set of features from one layer that are wholly contained by a feature from another layer. A feature is within another feature if the interiors of the features intersect, but the interior of the within feature does not intersect the boundary of the containing feature. The two features can share some boundary.

Parameters:

  • aLayer1 (GM_LayerHandle_t32) – First layer in predicate

  • aLayer2 (GM_LayerHandle_t32) – Second layer in predicate

  • aParams (GM_SpatialOps_Params_t) – Parameters

Returns:

Error Code

Return type:

GM_Error_t32


BEFORE

AFTER
../_images/WithinBefore.png ../_images/WithinAfter.png

Example

The following is an example of SpatialWithin.

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, "OuterBlueCircle.shp"),
    gm.GM_LoadFlags_HideAllPrompts,
)
err_LoadLayerList2, array_pointer, array_size_param = gm.LoadLayerList(
    os.path.join(import_dir, "InnerRedCircle.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 = "Within_Result"
err_SpatialWithin = gm.SpatialWithin(
    layers_list[1], layers_list[0], 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_SpatialWithin
), f"SpatialWithin: Expected {gm.GM_Error_None}, got {err_SpatialWithin}"

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