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SpatialCircle

Updated
globalmapper.SpatialCircle(GM_LayerHandle_t32 aLayer, GM_SpatialOps_Params_t aParams, GM_Distance_t aDistance, GM_FeatureGrouping_t8 aGrouping, str aStr) → GM_Error_t32

The Circle spatial transform creates a new layer with a circle around the center point of each feature or collection of features. The aDistance parameter is the radius in the given units. If aDistance is 0, then it creates a minimum enclosing circle for the entire feature.

Parameters:

  • aLayer (GM_LayerHandle_t32) – Input layer

  • aParams (GM_SpatialOps_Params_t) – Parameters

  • aDistance (GM_Distance_t) – Circle radius

  • aGrouping (GM_FeatureGrouping_t8) – Grouping type

  • aStr (str) – The attribute list string; may be an empty string

Returns:

Error Code

Return type:

GM_Error_t32


BEFORE

AFTER
../_images/multShapes.png ../_images/CircleAfter.png

Example

The following is an example of SpatialCircle.

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_LoadLayerList, array_pointer, array_size_param = gm.LoadLayerList(
    os.path.join(import_dir, "multShapes.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.mResultLayerName = "Circle_Result"
dist = gm.GM_Distance_t()
dist.mDistance = 0.0
dist.mUnits = gm.GM_DistUnit_Kilometers
err_SpatialCircle = gm.SpatialCircle(
    layers_list[0], spatial_params, dist, gm.GM_GroupingNone, ""
)

### END SAMPLE

assert (
    gm.GM_Error_None == err_LoadLayerList
), f"LoadLayerList: Expected {gm.GM_Error_None}, got {err_LoadLayerList}"
assert (
    gm.GM_Error_None == err_SpatialCircle
), f"SpatialCircle: Expected {gm.GM_Error_None}, got {err_SpatialCircle}"

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