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Add iOS bindings for cluster properties (#15515)

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This commit is contained in:
Jordan Kiley
2019-10-11 13:46:41 -07:00
committed by GitHub
parent a1f124c394
commit e4e2a78033
11 changed files with 244 additions and 8 deletions
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32
platform/darwin/src/MGLShapeSource.h
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@@ -41,6 +41,38 @@ FOUNDATION_EXTERN MGL_EXPORT const MGLShapeSourceOption MGLShapeSourceOptionClus
*/
FOUNDATION_EXTERN MGL_EXPORT const MGLShapeSourceOption MGLShapeSourceOptionClusterRadius;
/**
An `NSDictionary` object where the key is an `NSString`. The dictionary key will
be the feature attribute key. The resulting attribute value is
aggregated from the clustered points. The dictionary value is an `NSArray`
consisting of two `NSExpression` objects.
The first object determines how the attribute values are accumulated from the
cluster points. It is an `NSExpression` with an expression function that accepts
two or more arguments, such as `sum` or `max`. The arguments should be
`featureAccumulated` and the previously defined feature attribute key. The
resulting value is assigned to the specified attribute key.
The second `NSExpression` in the array determines which
attribute values are accessed from individual features within a cluster.
```swift
let firstExpression = NSExpression(format: "sum:({$featureAccumulated, sumValue})")
let secondExpression = NSExpression(forKeyPath: "magnitude")
let clusterPropertiesDictionary = ["sumValue" : [firstExpression, secondExpression]]
let options : [MGLShapeSourceOption : Any] = [.clustered : true,
.clusterProperties: clusterPropertiesDictionary]
```
This option corresponds to the
<a href="https://www.mapbox.com/mapbox-gl-style-spec/#sources-geojson-clusterProperties"><code>clusterProperties</code></a>
source property in the Mapbox Style Specification.
This option only affects point features within an `MGLShapeSource` object; it
is ignored when creating an `MGLComputedShapeSource` object.
*/
FOUNDATION_EXTERN MGL_EXPORT const MGLShapeSourceOption MGLShapeSourceOptionClusterProperties;
/**
An `NSNumber` object containing an integer; specifies the maximum zoom level at
which to cluster points if clustering is enabled. Defaults to one zoom level

53
platform/darwin/src/MGLShapeSource.mm
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@@ -3,6 +3,7 @@
#import "MGLLoggingConfiguration_Private.h"
#import "MGLStyle_Private.h"
#import "MGLStyleValue_Private.h"
#import "MGLMapView_Private.h"
#import "MGLSource_Private.h"
#import "MGLFeature_Private.h"
@@ -19,6 +20,7 @@
const MGLShapeSourceOption MGLShapeSourceOptionBuffer = @"MGLShapeSourceOptionBuffer";
const MGLShapeSourceOption MGLShapeSourceOptionClusterRadius = @"MGLShapeSourceOptionClusterRadius";
const MGLShapeSourceOption MGLShapeSourceOptionClustered = @"MGLShapeSourceOptionClustered";
const MGLShapeSourceOption MGLShapeSourceOptionClusterProperties = @"MGLShapeSourceOptionClusterProperties";
const MGLShapeSourceOption MGLShapeSourceOptionMaximumZoomLevel = @"MGLShapeSourceOptionMaximumZoomLevel";
const MGLShapeSourceOption MGLShapeSourceOptionMaximumZoomLevelForClustering = @"MGLShapeSourceOptionMaximumZoomLevelForClustering";
const MGLShapeSourceOption MGLShapeSourceOptionMinimumZoomLevel = @"MGLShapeSourceOptionMinimumZoomLevel";
@@ -84,6 +86,57 @@ mbgl::style::GeoJSONOptions MGLGeoJSONOptionsFromDictionary(NSDictionary<MGLShap
geoJSONOptions.cluster = value.boolValue;
}
if (NSDictionary *value = options[MGLShapeSourceOptionClusterProperties]) {
if (![value isKindOfClass:[NSDictionary<NSString *, NSArray *> class]]) {
[NSException raise:NSInvalidArgumentException
format:@"MGLShapeSourceOptionClusterProperties must be an NSDictionary with an NSString as a key and an array containing two NSExpression objects as a value."];
}
NSEnumerator *stringEnumerator = [value keyEnumerator];
NSString *key;
while (key = [stringEnumerator nextObject]) {
NSArray *expressionsArray = value[key];
if (![expressionsArray isKindOfClass:[NSArray class]]) {
[NSException raise:NSInvalidArgumentException
format:@"MGLShapeSourceOptionClusterProperties dictionary member value must be an array containing two objects."];
}
// Check that the array has 2 values. One should be a the reduce expression and one should be the map expression.
if ([expressionsArray count] != 2) {
[NSException raise:NSInvalidArgumentException
format:@"MGLShapeSourceOptionClusterProperties member value requires array of two objects."];
}
// reduceExpression should be a valid NSExpression
NSExpression *reduceExpression = expressionsArray[0];
if (![reduceExpression isKindOfClass:[NSExpression class]]) {
[NSException raise:NSInvalidArgumentException
format:@"MGLShapeSourceOptionClusterProperties array value requires two expression objects."];
}
auto reduce = MGLClusterPropertyFromNSExpression(reduceExpression);
if (!reduce) {
[NSException raise:NSInvalidArgumentException
format:@"Failed to convert MGLShapeSourceOptionClusterProperties reduce expression."];
}
// mapExpression should be a valid NSExpression
NSExpression *mapExpression = expressionsArray[1];
if (![mapExpression isKindOfClass:[NSExpression class]]) {
[NSException raise:NSInvalidArgumentException
format:@"MGLShapeSourceOptionClusterProperties member value must contain a valid NSExpression."];
}
auto map = MGLClusterPropertyFromNSExpression(mapExpression);
if (!map) {
[NSException raise:NSInvalidArgumentException
format:@"Failed to convert MGLShapeSourceOptionClusterProperties map expression."];
}
std::string keyString = std::string([key UTF8String]);
geoJSONOptions.clusterProperties.emplace(keyString, std::make_pair(std::move(map), std::move(reduce)));
}
}
if (NSNumber *value = options[MGLShapeSourceOptionLineDistanceMetrics]) {
if (![value isKindOfClass:[NSNumber class]]) {
[NSException raise:NSInvalidArgumentException

13
platform/darwin/src/MGLStyleValue.mm
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@@ -44,3 +44,16 @@ id MGLJSONObjectFromMBGLValue(const mbgl::Value &value) {
id MGLJSONObjectFromMBGLExpression(const mbgl::style::expression::Expression &mbglExpression) {
return MGLJSONObjectFromMBGLValue(mbglExpression.serialize());
}
std::unique_ptr<mbgl::style::expression::Expression> MGLClusterPropertyFromNSExpression(NSExpression *expression) {
if (!expression) {
return nullptr;
}
NSArray *jsonExpression = expression.mgl_jsonExpressionObject;
auto expr = mbgl::style::expression::dsl::createExpression(mbgl::style::conversion::makeConvertible(jsonExpression));
return expr;
}

5
platform/darwin/src/MGLStyleValue_Private.h
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@@ -12,12 +12,15 @@
#include <mbgl/style/conversion/color_ramp_property_value.hpp>
#include <mbgl/style/conversion/property_value.hpp>
#include <mbgl/style/conversion/position.hpp>
#include <mbgl/style/expression/dsl.hpp>
#import <mbgl/style/transition_options.hpp>
#import <mbgl/style/types.hpp>
#import <mbgl/util/enum.hpp>
#include <mbgl/util/interpolate.hpp>
#include <memory>
#if TARGET_OS_IPHONE
#import "UIColor+MGLAdditions.h"
#else
@@ -45,6 +48,8 @@ NS_INLINE mbgl::style::TransitionOptions MGLOptionsFromTransition(MGLTransition
return options;
}
std::unique_ptr<mbgl::style::expression::Expression> MGLClusterPropertyFromNSExpression(NSExpression *expression);
id MGLJSONObjectFromMBGLExpression(const mbgl::style::expression::Expression &mbglExpression);
template <typename MBGLType, typename ObjCType, typename MBGLElement = MBGLType, typename ObjCEnum = ObjCType>

7
platform/darwin/src/NSExpression+MGLAdditions.h
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@@ -84,6 +84,13 @@ FOUNDATION_EXTERN MGL_EXPORT const MGLExpressionInterpolationMode MGLExpressionI
*/
@property (class, nonatomic, readonly) NSExpression *featureIdentifierVariableExpression;
/**
`NSExpression` variable that corresponds to the
<a href="https://docs.mapbox.com/mapbox-gl-js/style-spec/#accumulated"><code>id</code></a>
expression operator in the Mapbox Style Specification.
*/
@property (class, nonatomic, readonly) NSExpression *featureAccumulatedVariableExpression;
/**
`NSExpression` variable that corresponds to the
<a href="https://www.mapbox.com/mapbox-gl-js/style-spec/#expressions-properties"><code>properties</code></a>

43
platform/darwin/src/NSExpression+MGLAdditions.mm
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@@ -553,6 +553,10 @@ const MGLExpressionInterpolationMode MGLExpressionInterpolationModeCubicBezier =
return [NSExpression expressionForVariable:@"lineProgress"];
}
+ (NSExpression *)featureAccumulatedVariableExpression {
return [NSExpression expressionForVariable:@"featureAccumulated"];
}
+ (NSExpression *)geometryTypeVariableExpression {
return [NSExpression expressionForVariable:@"geometryType"];
}
@@ -648,7 +652,6 @@ NSArray *MGLSubexpressionsWithJSONObjects(NSArray *objects) {
@"let": @"MGL_LET",
};
});
if (!object || object == [NSNull null]) {
return [NSExpression expressionForConstantValue:nil];
}
@@ -667,11 +670,10 @@ NSArray *MGLSubexpressionsWithJSONObjects(NSArray *objects) {
}];
return [NSExpression expressionForConstantValue:dictionary];
}
if ([object isKindOfClass:[NSArray class]]) {
NSArray *array = (NSArray *)object;
NSString *op = array.firstObject;
if (![op isKindOfClass:[NSString class]]) {
NSArray *subexpressions = MGLSubexpressionsWithJSONObjects(array);
return [NSExpression expressionForFunction:@"MGL_FUNCTION" arguments:subexpressions];
@@ -839,6 +841,8 @@ NSArray *MGLSubexpressionsWithJSONObjects(NSArray *objects) {
return NSExpression.heatmapDensityVariableExpression;
} else if ([op isEqualToString:@"line-progress"]) {
return NSExpression.lineProgressVariableExpression;
} else if ([op isEqualToString:@"accumulated"]) {
return NSExpression.featureAccumulatedVariableExpression;
} else if ([op isEqualToString:@"geometry-type"]) {
return NSExpression.geometryTypeVariableExpression;
} else if ([op isEqualToString:@"id"]) {
@@ -961,6 +965,9 @@ NSArray *MGLSubexpressionsWithJSONObjects(NSArray *objects) {
if ([self.variable isEqualToString:@"zoomLevel"]) {
return @[@"zoom"];
}
if ([self.variable isEqualToString:@"featureAccumulated"]) {
return @[@"accumulated"];
}
if ([self.variable isEqualToString:@"geometryType"]) {
return @[@"geometry-type"];
}
@@ -1046,6 +1053,8 @@ NSArray *MGLSubexpressionsWithJSONObjects(NSArray *objects) {
case NSFunctionExpressionType: {
NSString *function = self.function;
BOOL hasCollectionProperty = !( ! [self.arguments.firstObject isKindOfClass: [NSExpression class]] || self.arguments.firstObject.expressionType != NSAggregateExpressionType || self.arguments.firstObject.expressionType == NSSubqueryExpressionType);
NSString *op = MGLExpressionOperatorsByFunctionNames[function];
if (op) {
NSArray *arguments = self.arguments.mgl_jsonExpressionObject;
@@ -1057,16 +1066,31 @@ NSArray *MGLSubexpressionsWithJSONObjects(NSArray *objects) {
NSExpression *count = [NSExpression expressionForFunction:@"count:" arguments:self.arguments];
return [NSExpression expressionForFunction:@"divide:by:" arguments:@[sum, count]].mgl_jsonExpressionObject;
} else if ([function isEqualToString:@"sum:"]) {
NSArray *arguments = [self.arguments.firstObject.collection valueForKeyPath:@"mgl_jsonExpressionObject"];
NSArray *arguments;
if (hasCollectionProperty) {
arguments = [self.arguments.firstObject.collection valueForKeyPath:@"mgl_jsonExpressionObject"];
} else {
arguments = [self.arguments valueForKeyPath:@"mgl_jsonExpressionObject"];
}
return [@[@"+"] arrayByAddingObjectsFromArray:arguments];
} else if ([function isEqualToString:@"count:"]) {
NSArray *arguments = self.arguments.firstObject.mgl_jsonExpressionObject;
return @[@"length", arguments];
} else if ([function isEqualToString:@"min:"]) {
NSArray *arguments = [self.arguments.firstObject.collection valueForKeyPath:@"mgl_jsonExpressionObject"];
NSArray *arguments;
if (!hasCollectionProperty) {
arguments = [self.arguments valueForKeyPath:@"mgl_jsonExpressionObject"];
} else {
arguments = [self.arguments.firstObject.collection valueForKeyPath:@"mgl_jsonExpressionObject"];
}
return [@[@"min"] arrayByAddingObjectsFromArray:arguments];
} else if ([function isEqualToString:@"max:"]) {
NSArray *arguments = [self.arguments.firstObject.collection valueForKeyPath:@"mgl_jsonExpressionObject"];
NSArray *arguments;
if (!hasCollectionProperty) {
arguments = [self.arguments valueForKeyPath:@"mgl_jsonExpressionObject"];
} else {
arguments = [self.arguments.firstObject.collection valueForKeyPath:@"mgl_jsonExpressionObject"];
}
return [@[@"max"] arrayByAddingObjectsFromArray:arguments];
} else if ([function isEqualToString:@"exp:"]) {
return [NSExpression expressionForFunction:@"raise:toPower:" arguments:@[@(M_E), self.arguments.firstObject]].mgl_jsonExpressionObject;
@@ -1074,7 +1098,12 @@ NSArray *MGLSubexpressionsWithJSONObjects(NSArray *objects) {
return [NSExpression expressionWithFormat:@"%@ - modulus:by:(%@, 1)",
self.arguments.firstObject, self.arguments.firstObject].mgl_jsonExpressionObject;
} else if ([function isEqualToString:@"mgl_join:"]) {
NSArray *arguments = [self.arguments.firstObject.collection valueForKeyPath:@"mgl_jsonExpressionObject"];
NSArray *arguments;
if (!hasCollectionProperty) {
arguments = [self.arguments valueForKeyPath:@"mgl_jsonExpressionObject"];
} else {
arguments = [self.arguments.firstObject.collection valueForKeyPath:@"mgl_jsonExpressionObject"];
}
return [@[@"concat"] arrayByAddingObjectsFromArray:arguments];
} else if ([function isEqualToString:@"stringByAppendingString:"]) {
NSArray *arguments = self.arguments.mgl_jsonExpressionObject;

34
platform/darwin/test/MGLDocumentationExampleTests.swift
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@@ -554,7 +554,39 @@ class MGLDocumentationExampleTests: XCTestCase, MGLMapViewDelegate {
XCTAssertNotNil(attributedExpression)
}
func testMGLShapeSourceOptionClusterProperties() {
//#-example-code
let firstExpression = NSExpression(format: "sum:({$featureAccumulated, sumValue})")
let secondExpression = NSExpression(forKeyPath: "magnitude")
let clusterPropertiesDictionary = ["sumValue" : [firstExpression, secondExpression]]
let options : [MGLShapeSourceOption : Any] = [.clustered : true,
.clusterProperties: clusterPropertiesDictionary]
//#-end-example-code
let geoJSON: [String: Any] = [
"type" : "Feature",
"geometry" : [
"coordinates" : [
-77.00896639534831,
38.87031006108791,
0.0
],
"type" : "Point"
],
"properties" : [
"cluster" : true,
"cluster_id" : 123,
"point_count" : 4567,
]
]
let clusterShapeData = try! JSONSerialization.data(withJSONObject: geoJSON, options: [])
let shape = try! MGLShape(data: clusterShapeData, encoding: String.Encoding.utf8.rawValue)
let source = MGLShapeSource(identifier: "source", shape: shape, options: options)
mapView.style?.addSource(source)
}
// For testMGLMapView().
func myCustomFunction() {}
}

55
platform/darwin/test/MGLExpressionTests.mm
View File

@@ -179,6 +179,13 @@ using namespace std::string_literals;
NSMutableDictionary *context = [@{@"lineProgress": @1} mutableCopy];
XCTAssertEqualObjects([expression expressionValueWithObject:nil context:context], @1);
}
{
NSExpression *expression = [NSExpression expressionForVariable:@"featureAccumulated"];
XCTAssertEqualObjects(expression.mgl_jsonExpressionObject, @[@"accumulated"]);
XCTAssertEqualObjects([NSExpression expressionWithFormat:@"$featureAccumulated"].mgl_jsonExpressionObject, @[@"accumulated"]);
XCTAssertEqualObjects([NSExpression expressionWithMGLJSONObject:@[@"accumulated"]], expression);
}
{
NSExpression *expression = [NSExpression expressionForVariable:@"geometryType"];
XCTAssertEqualObjects(expression.mgl_jsonExpressionObject, @[@"geometry-type"]);
@@ -380,6 +387,26 @@ using namespace std::string_literals;
XCTAssertEqualObjects([NSExpression expressionWithFormat:@"1 + 1"].mgl_jsonExpressionObject, jsonExpression);
XCTAssertEqualObjects([NSExpression expressionWithMGLJSONObject:jsonExpression], expression);
}
{
NSExpression *testExpression = [NSExpression expressionWithFormat:@"sum:({1, 1, 2})"];
NSExpression *expression = [NSExpression expressionForFunction:@"sum:" arguments:@[[NSExpression expressionForAggregate:@[MGLConstantExpression(@1), MGLConstantExpression(@1), MGLConstantExpression(@2)]]]];
NSArray *jsonExpression = @[@"+", @1, @1, @2];
XCTAssertEqualObjects(testExpression.mgl_jsonExpressionObject, jsonExpression);
XCTAssertEqualObjects(expression.mgl_jsonExpressionObject, jsonExpression);
XCTAssertEqualObjects(expression, testExpression);
}
{
NSExpression *expression = [NSExpression expressionForFunction:@"sum:" arguments:@[MGLConstantExpression(@1), MGLConstantExpression(@1), MGLConstantExpression(@2)]];
NSArray *jsonExpression = @[@"+", @1, @1, @2];
XCTAssertEqualObjects(expression.mgl_jsonExpressionObject, jsonExpression);
// - [NSExpression expressionWithMGLJSONObject:] creates an expression with an aggregate expression as an argument. This is not equal to an expression with an array of expressions as an argument. For testing purposes, we will compare their operands and arrays of expressions.
NSExpression *aggregateExpression = [NSExpression expressionWithMGLJSONObject:jsonExpression];
XCTAssertEqualObjects(aggregateExpression.operand, expression.operand);
XCTAssertEqualObjects(aggregateExpression.arguments.firstObject.collection, expression.arguments);
}
{
NSArray *threeArguments = @[MGLConstantExpression(@1), MGLConstantExpression(@1), MGLConstantExpression(@1)];
NSExpression *expression = [NSExpression expressionForFunction:@"add:to:" arguments:threeArguments];
@@ -417,6 +444,24 @@ using namespace std::string_literals;
// NSExpression lacks a shorthand operator for modulus.
XCTAssertEqualObjects([NSExpression expressionWithMGLJSONObject:jsonExpression], expression);
}
{
NSExpression *expression = [NSExpression expressionForFunction:@"max:" arguments:arguments];
NSArray *jsonExpression = @[@"max", @1, @1];
XCTAssertEqualObjects(expression.mgl_jsonExpressionObject, jsonExpression);
NSExpression *aggregateExpression = [NSExpression expressionWithMGLJSONObject:jsonExpression];
XCTAssertEqualObjects(aggregateExpression.operand, expression.operand);
XCTAssertEqualObjects(aggregateExpression.arguments.firstObject.collection, expression.arguments);
}
{
NSExpression *expression = [NSExpression expressionForFunction:@"min:" arguments:arguments];
NSArray *jsonExpression = @[@"min", @1, @1];
XCTAssertEqualObjects(expression.mgl_jsonExpressionObject, jsonExpression);
NSExpression *aggregateExpression = [NSExpression expressionWithMGLJSONObject:jsonExpression];
XCTAssertEqualObjects(aggregateExpression.operand, expression.operand);
XCTAssertEqualObjects(aggregateExpression.arguments.firstObject.collection, expression.arguments);
}
{
NSExpression *expression = [NSExpression expressionForFunction:@"ceiling:" arguments:@[MGLConstantExpression(@1.5)]];
NSArray *jsonExpression = @[@"ceil", @1.5];
@@ -621,6 +666,16 @@ using namespace std::string_literals;
XCTAssertEqualObjects([aftermarketExpression expressionValueWithObject:nil context:nil], @"OldMacDonald");
XCTAssertEqualObjects([NSExpression expressionWithMGLJSONObject:jsonExpression], aftermarketExpression);
}
{
NSExpression *expression = [NSExpression expressionForFunction:@"mgl_join:" arguments:@[@"Old", @"MacDonald"]];
NSExpression *aftermarketExpression = [NSExpression expressionWithFormat:@"mgl_join({'Old', 'MacDonald'})"];
NSArray *jsonExpression = @[@"concat", @"Old", @"MacDonald"];
XCTAssertEqualObjects(expression.mgl_jsonExpressionObject, jsonExpression);
XCTAssertEqualObjects(aftermarketExpression.mgl_jsonExpressionObject, expression.mgl_jsonExpressionObject);
NSExpression *aggregateExpression = [NSExpression expressionWithMGLJSONObject:jsonExpression];
XCTAssertEqualObjects(aggregateExpression.operand, expression.operand);
}
{
NSExpression *expression = [NSExpression expressionForFunction:@"uppercase:" arguments:arguments];
NSArray *jsonExpression = @[@"upcase", @"MacDonald"];

5
platform/darwin/test/MGLShapeSourceTests.mm
View File

@@ -13,8 +13,12 @@
@implementation MGLShapeSourceTests
- (void)testGeoJSONOptionsFromDictionary {
NSExpression *reduceExpression = [NSExpression expressionForFunction:@"sum:" arguments:@[[NSExpression expressionForKeyPath:@"featureAccumulated"], [NSExpression expressionForKeyPath:@"sumValue"]]];
NSExpression *mapExpression = [NSExpression expressionForKeyPath:@"mag"];
NSArray *clusterPropertyArray = @[reduceExpression, mapExpression];
NSDictionary *options = @{MGLShapeSourceOptionClustered: @YES,
MGLShapeSourceOptionClusterRadius: @42,
MGLShapeSourceOptionClusterProperties: @{@"sumValue": clusterPropertyArray},
MGLShapeSourceOptionMaximumZoomLevelForClustering: @98,
MGLShapeSourceOptionMaximumZoomLevel: @99,
MGLShapeSourceOptionBuffer: @1976,
@@ -29,6 +33,7 @@
XCTAssertEqual(mbglOptions.buffer, 1976);
XCTAssertEqual(mbglOptions.tolerance, 0.42);
XCTAssertTrue(mbglOptions.lineMetrics);
XCTAssertTrue(!mbglOptions.clusterProperties.empty());
options = @{MGLShapeSourceOptionClustered: @"number 1"};
XCTAssertThrows(MGLGeoJSONOptionsFromDictionary(options));

4
platform/ios/CHANGELOG.md
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@@ -14,6 +14,10 @@ Mapbox welcomes participation and contributions from everyone. Please read [CONT
* Improved rendering performance for the styles with multiple sources ([#15756](https://github.com/mapbox/mapbox-gl-native/pull/15756))
### Styles and rendering
* Added an `MGLShapeSourceOptionClusterProperties` option that allows styling individual clusters based on aggregated feature data. ([#15515](https://github.com/mapbox/mapbox-gl-native/pull/15515))
### Other changes
* Added `-[MGLMapSnapshotOverlay coordinateForPoint:]` and `-[MGLMapSnapshotOverlay pointForCoordinate:]` to convert between context and map coordinates, mirroring those of `MGLMapSnapshot`. ([#15746](https://github.com/mapbox/mapbox-gl-native/pull/15746))

1
src/mbgl/style/sources/geojson_source_impl.cpp
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@@ -99,6 +99,7 @@ GeoJSONSource::Impl::Impl(const Impl& other, const GeoJSON& geoJSON)
Feature feature;
clusterOptions.map = [&](const PropertyMap& properties) -> PropertyMap {
PropertyMap ret{};
if (properties.empty()) return ret;
for (const auto& p : options.clusterProperties) {
feature.properties = properties;
ret[p.first] = evaluateFeature<Value>(feature, p.second.first);