2 files changed, 128 insertions, 3 deletions

diff --git a/platform/darwin/src/MGLSymbolStyleLayer.h b/platform/darwin/src/MGLSymbolStyleLayer.h
index d8dded7dbd..bc39df5b16 100644
--- a/platform/darwin/src/MGLSymbolStyleLayer.h
+++ b/platform/darwin/src/MGLSymbolStyleLayer.h
@@ -8,6 +8,51 @@
 NS_ASSUME_NONNULL_BEGIN
 
 /**
+ Part of the icon placed closest to the anchor.
+
+ Values of this type are used in the `MGLSymbolStyleLayer.iconAnchor`
+ property.
+ */
+typedef NS_ENUM(NSUInteger, MGLIconAnchor) {
+    /**
+     The center of the icon is placed closest to the anchor.
+     */
+    MGLIconAnchorCenter,
+    /**
+     The left side of the icon is placed closest to the anchor.
+     */
+    MGLIconAnchorLeft,
+    /**
+     The right side of the icon is placed closest to the anchor.
+     */
+    MGLIconAnchorRight,
+    /**
+     The top of the icon is placed closest to the anchor.
+     */
+    MGLIconAnchorTop,
+    /**
+     The bottom of the icon is placed closest to the anchor.
+     */
+    MGLIconAnchorBottom,
+    /**
+     The top left corner of the icon is placed closest to the anchor.
+     */
+    MGLIconAnchorTopLeft,
+    /**
+     The top right corner of the icon is placed closest to the anchor.
+     */
+    MGLIconAnchorTopRight,
+    /**
+     The bottom left corner of the icon is placed closest to the anchor.
+     */
+    MGLIconAnchorBottomLeft,
+    /**
+     The bottom right corner of the icon is placed closest to the anchor.
+     */
+    MGLIconAnchorBottomRight,
+};
+
+/**
  Orientation of icon when map is pitched.
 
  Values of this type are used in the `MGLSymbolStyleLayer.iconPitchAlignment`
@@ -345,6 +390,34 @@ MGL_EXPORT
 @property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *iconAllowOverlap __attribute__((unavailable("Use iconAllowsOverlap instead.")));
 
 /**
+ Part of the icon placed closest to the anchor.
+ 
+ The default value of this property is an `MGLStyleValue` object containing an
+ `NSValue` object containing `MGLIconAnchorCenter`. Set this property to `nil`
+ to reset it to the default value.
+ 
+ This property is only applied to the style if `iconImageName` is non-`nil`.
+ Otherwise, it is ignored.
+ 
+ You can set this property to an instance of:
+ 
+ * `MGLConstantStyleValue`
+ * `MGLCameraStyleFunction` with an interpolation mode of:
+   * `MGLInterpolationModeExponential`
+   * `MGLInterpolationModeInterval`
+ * `MGLSourceStyleFunction` with an interpolation mode of:
+   * `MGLInterpolationModeExponential`
+   * `MGLInterpolationModeInterval`
+   * `MGLInterpolationModeCategorical`
+   * `MGLInterpolationModeIdentity`
+ * `MGLCompositeStyleFunction` with an interpolation mode of:
+   * `MGLInterpolationModeExponential`
+   * `MGLInterpolationModeInterval`
+   * `MGLInterpolationModeCategorical`
+ */
+@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *iconAnchor;
+
+/**
  If true, other symbols can be visible even if they collide with the icon.
  
  The default value of this property is an `MGLStyleValue` object containing an
@@ -1984,6 +2057,19 @@ MGL_EXPORT
 #pragma mark Working with Symbol Style Layer Attribute Values
 
 /**
+ Creates a new value object containing the given `MGLIconAnchor` enumeration.
+
+ @param iconAnchor The value for the new object.
+ @return A new value object that contains the enumeration value.
+ */
++ (instancetype)valueWithMGLIconAnchor:(MGLIconAnchor)iconAnchor;
+
+/**
+ The `MGLIconAnchor` enumeration representation of the value.
+ */
+@property (readonly) MGLIconAnchor MGLIconAnchorValue;
+
+/**
  Creates a new value object containing the given `MGLIconPitchAlignment` enumeration.
 
  @param iconPitchAlignment The value for the new object.
diff --git a/platform/darwin/src/MGLSymbolStyleLayer.mm b/platform/darwin/src/MGLSymbolStyleLayer.mm
index 2541e6b0a4..7e8b0b247b 100644
--- a/platform/darwin/src/MGLSymbolStyleLayer.mm
+++ b/platform/darwin/src/MGLSymbolStyleLayer.mm
@@ -13,6 +13,18 @@
 
 namespace mbgl {
 
+    MBGL_DEFINE_ENUM(MGLIconAnchor, {
+        { MGLIconAnchorCenter, "center" },
+        { MGLIconAnchorLeft, "left" },
+        { MGLIconAnchorRight, "right" },
+        { MGLIconAnchorTop, "top" },
+        { MGLIconAnchorBottom, "bottom" },
+        { MGLIconAnchorTopLeft, "top-left" },
+        { MGLIconAnchorTopRight, "top-right" },
+        { MGLIconAnchorBottomLeft, "bottom-left" },
+        { MGLIconAnchorBottomRight, "bottom-right" },
+    });
+
     MBGL_DEFINE_ENUM(MGLIconPitchAlignment, {
         { MGLIconPitchAlignmentMap, "map" },
         { MGLIconPitchAlignmentViewport, "viewport" },
@@ -166,6 +178,23 @@ namespace mbgl {
     return self.iconAllowsOverlap;
 }
 
+- (void)setIconAnchor:(MGLStyleValue<NSValue *> *)iconAnchor {
+    MGLAssertStyleLayerIsValid();
+
+    auto mbglValue = MGLStyleValueTransformer<mbgl::style::SymbolAnchorType, NSValue *, mbgl::style::SymbolAnchorType, MGLIconAnchor>().toDataDrivenPropertyValue(iconAnchor);
+    self.rawLayer->setIconAnchor(mbglValue);
+}
+
+- (MGLStyleValue<NSValue *> *)iconAnchor {
+    MGLAssertStyleLayerIsValid();
+
+    auto propertyValue = self.rawLayer->getIconAnchor();
+    if (propertyValue.isUndefined()) {
+        return MGLStyleValueTransformer<mbgl::style::SymbolAnchorType, NSValue *, mbgl::style::SymbolAnchorType, MGLIconAnchor>().toDataDrivenStyleValue(self.rawLayer->getDefaultIconAnchor());
+    }
+    return MGLStyleValueTransformer<mbgl::style::SymbolAnchorType, NSValue *, mbgl::style::SymbolAnchorType, MGLIconAnchor>().toDataDrivenStyleValue(propertyValue);
+}
+
 - (void)setIconIgnoresPlacement:(MGLStyleValue<NSNumber *> *)iconIgnoresPlacement {
     MGLAssertStyleLayerIsValid();
 
@@ -586,7 +615,7 @@ namespace mbgl {
 - (void)setTextAnchor:(MGLStyleValue<NSValue *> *)textAnchor {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<mbgl::style::TextAnchorType, NSValue *, mbgl::style::TextAnchorType, MGLTextAnchor>().toDataDrivenPropertyValue(textAnchor);
+    auto mbglValue = MGLStyleValueTransformer<mbgl::style::SymbolAnchorType, NSValue *, mbgl::style::SymbolAnchorType, MGLTextAnchor>().toDataDrivenPropertyValue(textAnchor);
     self.rawLayer->setTextAnchor(mbglValue);
 }
 
@@ -595,9 +624,9 @@ namespace mbgl {
 
     auto propertyValue = self.rawLayer->getTextAnchor();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<mbgl::style::TextAnchorType, NSValue *, mbgl::style::TextAnchorType, MGLTextAnchor>().toDataDrivenStyleValue(self.rawLayer->getDefaultTextAnchor());
+        return MGLStyleValueTransformer<mbgl::style::SymbolAnchorType, NSValue *, mbgl::style::SymbolAnchorType, MGLTextAnchor>().toDataDrivenStyleValue(self.rawLayer->getDefaultTextAnchor());
     }
-    return MGLStyleValueTransformer<mbgl::style::TextAnchorType, NSValue *, mbgl::style::TextAnchorType, MGLTextAnchor>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<mbgl::style::SymbolAnchorType, NSValue *, mbgl::style::SymbolAnchorType, MGLTextAnchor>().toDataDrivenStyleValue(propertyValue);
 }
 
 - (void)setTextFontNames:(MGLStyleValue<NSArray<NSString *> *> *)textFontNames {
@@ -1344,6 +1373,16 @@ namespace mbgl {
 
 @implementation NSValue (MGLSymbolStyleLayerAdditions)
 
++ (NSValue *)valueWithMGLIconAnchor:(MGLIconAnchor)iconAnchor {
+    return [NSValue value:&iconAnchor withObjCType:@encode(MGLIconAnchor)];
+}
+
+- (MGLIconAnchor)MGLIconAnchorValue {
+    MGLIconAnchor iconAnchor;
+    [self getValue:&iconAnchor];
+    return iconAnchor;
+}
+
 + (NSValue *)valueWithMGLIconPitchAlignment:(MGLIconPitchAlignment)iconPitchAlignment {
     return [NSValue value:&iconPitchAlignment withObjCType:@encode(MGLIconPitchAlignment)];
 }