WIP compass visibility

13 files changed, 224 insertions, 85 deletions

diff --git a/platform/darwin/src/MGLTypes.h b/platform/darwin/src/MGLTypes.h
index 491e24310f..b8354d2e83 100644
--- a/platform/darwin/src/MGLTypes.h
+++ b/platform/darwin/src/MGLTypes.h
@@ -119,4 +119,16 @@ NS_INLINE MGLTransition MGLTransitionMake(NSTimeInterval duration, NSTimeInterva
     return transition;
 }
 
+/**
+ Constants indicating the visibility of different map ornaments.
+ */
+typedef NS_ENUM(NSInteger, MGLOrnamentVisibility) {
+    /** A constant indicating that the ornament adapts to the current map state. */
+    MGLOrnamentVisibilityAdaptive,
+    /** A constant indicating that the ornament is always hidden. */
+    MGLOrnamentVisibilityHidden,
+    /** A constant indicating that the ornament is always visible. */
+    MGLOrnamentVisibilityVisible
+};
+
 NS_ASSUME_NONNULL_END
diff --git a/platform/ios/app/MBXViewController.m b/platform/ios/app/MBXViewController.m
index 2fb95e1b17..2036d35fbe 100644
--- a/platform/ios/app/MBXViewController.m
+++ b/platform/ios/app/MBXViewController.m
@@ -302,6 +302,8 @@ CLLocationCoordinate2D randomWorldCoordinate() {
             }
         }
     }];
+
+    self.mapView.compassView.compassVisibility = MGLOrnamentVisibilityAdaptive;
 }
 
 - (UIInterfaceOrientationMask)supportedInterfaceOrientations
diff --git a/platform/ios/ios.xcodeproj/project.pbxproj b/platform/ios/ios.xcodeproj/project.pbxproj
index fbf7974be0..eb12c046e9 100644
--- a/platform/ios/ios.xcodeproj/project.pbxproj
+++ b/platform/ios/ios.xcodeproj/project.pbxproj
@@ -424,6 +424,11 @@
 		96E516FB20005A4000A02306 /* MGLUserLocationHeadingBeamLayer.h in Headers */ = {isa = PBXBuildFile; fileRef = 966FCF4A1F3A5C9200F2B6DE /* MGLUserLocationHeadingBeamLayer.h */; };
 		96E516FC20005A4400A02306 /* MGLUserLocationHeadingIndicator.h in Headers */ = {isa = PBXBuildFile; fileRef = 96F3F73B1F5711F1003E2D2C /* MGLUserLocationHeadingIndicator.h */; };
 		96E5170420005A6B00A02306 /* SMCalloutView.h in Headers */ = {isa = PBXBuildFile; fileRef = DA8848891CBB037E00AB86E3 /* SMCalloutView.h */; };
+		96E6145622CC135200109F14 /* MGLCompassViewTests.m in Sources */ = {isa = PBXBuildFile; fileRef = 96E6145522CC135200109F14 /* MGLCompassViewTests.m */; };
+		96E6145922CC169000109F14 /* MGLCompassButton.h in Headers */ = {isa = PBXBuildFile; fileRef = 96E6145722CC169000109F14 /* MGLCompassButton.h */; settings = {ATTRIBUTES = (Public, ); }; };
+		96E6145A22CC169000109F14 /* MGLCompassButton.h in Headers */ = {isa = PBXBuildFile; fileRef = 96E6145722CC169000109F14 /* MGLCompassButton.h */; settings = {ATTRIBUTES = (Public, ); }; };
+		96E6145B22CC169000109F14 /* MGLCompassButton.mm in Sources */ = {isa = PBXBuildFile; fileRef = 96E6145822CC169000109F14 /* MGLCompassButton.mm */; };
+		96E6145C22CC169000109F14 /* MGLCompassButton.mm in Sources */ = {isa = PBXBuildFile; fileRef = 96E6145822CC169000109F14 /* MGLCompassButton.mm */; };
 		96ED34DE22374C0900E9FCA9 /* MGLMapViewDirectionTests.mm in Sources */ = {isa = PBXBuildFile; fileRef = 96ED34DD22374C0900E9FCA9 /* MGLMapViewDirectionTests.mm */; };
 		96F3F73C1F57124B003E2D2C /* MGLUserLocationHeadingIndicator.h in Headers */ = {isa = PBXBuildFile; fileRef = 96F3F73B1F5711F1003E2D2C /* MGLUserLocationHeadingIndicator.h */; };
 		9C188C4F2242C95A0022FA55 /* MMEDate.m in Sources */ = {isa = PBXBuildFile; fileRef = 40834BBC1FE05D6E00C1BD0D /* MMEDate.m */; };
@@ -1132,6 +1137,9 @@
 		96E0272C1E57C7E5004B8E66 /* fr */ = {isa = PBXFileReference; lastKnownFileType = text.plist.strings; name = fr; path = fr.lproj/Localizable.strings; sourceTree = "<group>"; };
 		96E0272D1E57C7E6004B8E66 /* vi */ = {isa = PBXFileReference; lastKnownFileType = text.plist.strings; name = vi; path = vi.lproj/Localizable.strings; sourceTree = "<group>"; };
 		96E0272E1E57C7E7004B8E66 /* pt-BR */ = {isa = PBXFileReference; lastKnownFileType = text.plist.strings; name = "pt-BR"; path = "pt-BR.lproj/Localizable.strings"; sourceTree = "<group>"; };
+		96E6145522CC135200109F14 /* MGLCompassViewTests.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = MGLCompassViewTests.m; sourceTree = "<group>"; };
+		96E6145722CC169000109F14 /* MGLCompassButton.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = MGLCompassButton.h; sourceTree = "<group>"; };
+		96E6145822CC169000109F14 /* MGLCompassButton.mm */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.objcpp; path = MGLCompassButton.mm; sourceTree = "<group>"; };
 		96ED34DD22374C0900E9FCA9 /* MGLMapViewDirectionTests.mm */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.objcpp; path = MGLMapViewDirectionTests.mm; sourceTree = "<group>"; };
 		96F017292118FBAE00892778 /* MGLMapView_Experimental.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = MGLMapView_Experimental.h; sourceTree = "<group>"; };
 		96F3F73B1F5711F1003E2D2C /* MGLUserLocationHeadingIndicator.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = MGLUserLocationHeadingIndicator.h; sourceTree = "<group>"; };
@@ -1658,6 +1666,8 @@
 		355ADFF91E9281C300F3939D /* Views */ = {
 			isa = PBXGroup;
 			children = (
+				96E6145722CC169000109F14 /* MGLCompassButton.h */,
+				96E6145822CC169000109F14 /* MGLCompassButton.mm */,
 				355ADFFB1E9281DA00F3939D /* MGLScaleBar.h */,
 				355ADFFC1E9281DA00F3939D /* MGLScaleBar.mm */,
 			);
@@ -2026,6 +2036,7 @@
 				DA35A2C31CCA9F8300E826B2 /* MGLClockDirectionFormatterTests.m */,
 				35D9DDE11DA25EEC00DAAD69 /* MGLCodingTests.mm */,
 				DA35A2C41CCA9F8300E826B2 /* MGLCompassDirectionFormatterTests.m */,
+				96E6145522CC135200109F14 /* MGLCompassViewTests.m */,
 				DA35A2A91CCA058D00E826B2 /* MGLCoordinateFormatterTests.m */,
 				3598544C1E1D38AA00B29F84 /* MGLDistanceFormatterTests.m */,
 				6407D66F1E0085FD00F6A9C3 /* MGLDocumentationExampleTests.swift */,
@@ -2454,6 +2465,7 @@
 				74CB5EC3219B282500102936 /* MGLCircleStyleLayer_Private.h in Headers */,
 				DA8847F01CBAFA5100AB86E3 /* MGLAnnotation.h in Headers */,
 				400533011DB0862B0069F638 /* NSArray+MGLAdditions.h in Headers */,
+				96E6145922CC169000109F14 /* MGLCompassButton.h in Headers */,
 				1F06668A1EC64F8E001C16D7 /* MGLLight.h in Headers */,
 				4049C29D1DB6CD6C00B3F799 /* MGLPointCollection.h in Headers */,
 				40CF6DBB1DAC3C6600A4D18B /* MGLShape_Private.h in Headers */,
@@ -2645,6 +2657,7 @@
 				9C6E283922A982670056B7BE /* MMEEventLogReportViewController.h in Headers */,
 				1F6A82A92138871900BA5B41 /* MGLLoggingConfiguration_Private.h in Headers */,
 				DABFB8661CBE99E500D62B32 /* MGLPointAnnotation.h in Headers */,
+				96E6145A22CC169000109F14 /* MGLCompassButton.h in Headers */,
 				96E516E42000560B00A02306 /* MGLComputedShapeSource_Private.h in Headers */,
 				96E516E92000560B00A02306 /* MGLAnnotationImage_Private.h in Headers */,
 				96E516E52000560B00A02306 /* MGLOfflinePack_Private.h in Headers */,
@@ -3240,6 +3253,7 @@
 				40CFA6511D7875BB008103BD /* MGLShapeSourceTests.mm in Sources */,
 				DA35A2C51CCA9F8300E826B2 /* MGLClockDirectionFormatterTests.m in Sources */,
 				35B8E08C1D6C8B5100E768D2 /* MGLPredicateTests.mm in Sources */,
+				96E6145622CC135200109F14 /* MGLCompassViewTests.m in Sources */,
 				96036A0620059BBA00510F3D /* MGLNSOrthographyAdditionsTests.m in Sources */,
 				1F95931D1E6DE2E900D5B294 /* MGLNSDateAdditionsTests.mm in Sources */,
 				DA695426215B1E76002041A4 /* MGLMapCameraTests.m in Sources */,
@@ -3336,6 +3350,7 @@
 				3557F7B21E1D27D300CCA5E6 /* MGLDistanceFormatter.m in Sources */,
 				9C6E282B22A981570056B7BE /* MGLMapboxEvents.m in Sources */,
 				1FCCEC36222605C400302E3B /* MGLSDKMetricsManager.m in Sources */,
+				96E6145B22CC169000109F14 /* MGLCompassButton.mm in Sources */,
 				40834BE71FE05E1800C1BD0D /* MMEAPIClient.m in Sources */,
 				DA8848591CBAFB9800AB86E3 /* MGLMapView.mm in Sources */,
 				DA8848501CBAFB9800AB86E3 /* MGLAnnotationImage.m in Sources */,
@@ -3462,6 +3477,7 @@
 				1FCCEC37222605C400302E3B /* MGLSDKMetricsManager.m in Sources */,
 				9C6E282C22A981580056B7BE /* MGLMapboxEvents.m in Sources */,
 				DAA4E41F1CBB730400178DFB /* MGLMultiPoint.mm in Sources */,
+				96E6145C22CC169000109F14 /* MGLCompassButton.mm in Sources */,
 				DD0902AA1DB1929D00C5BDCE /* MGLNetworkConfiguration.m in Sources */,
 				40834C041FE05E1800C1BD0D /* MMELocationManager.m in Sources */,
 				9C6E281F22A980AC0056B7BE /* CLLocation+MMEMobileEvents.m in Sources */,
diff --git a/platform/ios/jazzy.yml b/platform/ios/jazzy.yml
index d459e93613..f5d0040ea5 100644
--- a/platform/ios/jazzy.yml
+++ b/platform/ios/jazzy.yml
@@ -57,6 +57,7 @@ custom_categories:
     children:
       - MGLCalloutView
       - MGLCalloutViewDelegate
+      - MGLCompassButton
   - name: Location Updates
     children:
       - MGLLocationManager
diff --git a/platform/ios/src/MGLCompassButton.h b/platform/ios/src/MGLCompassButton.h
new file mode 100644
index 0000000000..f42d5f315d
--- /dev/null
+++ b/platform/ios/src/MGLCompassButton.h
@@ -0,0 +1,26 @@
+#import <UIKit/UIKit.h>
+#import <CoreLocation/CoreLocation.h>
+
+#import "MGLTypes.h"
+
+NS_ASSUME_NONNULL_BEGIN
+
+/**
+ A specialized view that displays the current compass heading for its associated map.
+ */
+@interface MGLCompassButton : UIImageView
+
+/**
+ The visibility of the compass button.
+
+ You can configure a compass button to be visible all the time or only when the compass heading changes.
+ */
+@property (nonatomic, assign) MGLOrnamentVisibility compassVisibility;
+
+// TODO: Make these private
++ (instancetype)compassButton;
+- (void)updateCompassWithDirection:(CLLocationDirection)direction;
+
+@end
+
+NS_ASSUME_NONNULL_END
diff --git a/platform/ios/src/MGLCompassButton.mm b/platform/ios/src/MGLCompassButton.mm
new file mode 100644
index 0000000000..6d62793915
--- /dev/null
+++ b/platform/ios/src/MGLCompassButton.mm
@@ -0,0 +1,108 @@
+#import "MGLCompassButton.h"
+#import "MGLCompassDirectionFormatter.h"
+
+#import <Mapbox/MGLGeometry.h>
+
+#import "MGLMapView_Private.h"
+#import "UIImage+MGLAdditions.h"
+#import "NSBundle+MGLAdditions.h"
+
+#include <mbgl/math/wrap.hpp>
+
+@interface MGLCompassButton ()
+
+@property (nonatomic) MGLCompassDirectionFormatter *accessibilityCompassFormatter;
+
+@end
+
+@implementation MGLCompassButton
+
++ (instancetype)compassButton {
+    return [[MGLCompassButton alloc] init];
+}
+
+- (instancetype)init {
+    if (self = [super init]) {
+        [self commonInit];
+    }
+    return self;
+}
+
+- (void)commonInit {
+    self.image = self.compassImage;
+
+    self.compassVisibility = MGLOrnamentVisibilityAdaptive;
+
+    self.alpha = 0;
+    self.userInteractionEnabled = YES;
+    self.translatesAutoresizingMaskIntoConstraints = NO;
+
+    self.accessibilityTraits = UIAccessibilityTraitButton;
+    self.accessibilityLabel = NSLocalizedStringWithDefaultValue(@"COMPASS_A11Y_LABEL", nil, nil, @"Compass", @"Accessibility label");
+    self.accessibilityHint = NSLocalizedStringWithDefaultValue(@"COMPASS_A11Y_HINT", nil, nil, @"Rotates the map to face due north", @"Accessibility hint");
+
+    self.accessibilityCompassFormatter = [[MGLCompassDirectionFormatter alloc] init];
+    self.accessibilityCompassFormatter.unitStyle = NSFormattingUnitStyleLong;
+
+    [self sizeToFit];
+}
+
+- (UIImage *)compassImage {
+    UIImage *scaleImage = [UIImage mgl_resourceImageNamed:@"Compass"];
+    UIGraphicsBeginImageContextWithOptions(scaleImage.size, NO, UIScreen.mainScreen.scale);
+    [scaleImage drawInRect:{CGPointZero, scaleImage.size}];
+
+    NSAttributedString *north = [[NSAttributedString alloc] initWithString:NSLocalizedStringWithDefaultValue(@"COMPASS_NORTH", nil, nil, @"N", @"Compass abbreviation for north") attributes:@{
+        NSFontAttributeName: [UIFont systemFontOfSize:11 weight:UIFontWeightUltraLight],
+        NSForegroundColorAttributeName: [UIColor whiteColor],
+    }];
+    CGRect stringRect = CGRectMake((scaleImage.size.width - north.size.width) / 2,
+                                   scaleImage.size.height * 0.435,
+                                   north.size.width, north.size.height);
+    [north drawInRect:stringRect];
+
+    UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
+    UIGraphicsEndImageContext();
+    return image;
+}
+
+- (void)updateCompassWithDirection:(CLLocationDirection)direction
+{
+    CLLocationDirection plateDirection = mbgl::util::wrap(-direction, 0., 360.);
+    self.transform = CGAffineTransformMakeRotation(MGLRadiansFromDegrees(plateDirection));
+
+    self.isAccessibilityElement = direction > 0;
+    self.accessibilityValue = [self.accessibilityCompassFormatter stringFromDirection:direction];
+
+    switch (self.compassVisibility) {
+        case MGLOrnamentVisibilityAdaptive:
+            if (direction > 0 && self.alpha < 1) {
+                [self showCompass];
+            } else if (direction == 0 && self.alpha > 0) {
+                [self hideCompass];
+            }
+            break;
+        case MGLOrnamentVisibilityVisible:
+            [self showCompass];
+            break;
+        case MGLOrnamentVisibilityHidden:
+            [self hideCompass];
+            break;
+    }
+}
+
+- (void)showCompass {
+    [self animateToAlpha:1];
+}
+
+- (void)hideCompass {
+    [self animateToAlpha:0];
+}
+
+- (void)animateToAlpha:(CGFloat)alpha {
+    [UIView animateWithDuration:MGLAnimationDuration delay:0 options:UIViewAnimationOptionBeginFromCurrentState animations:^{
+         self.alpha = alpha;
+     } completion:nil];
+}
+
+@end
diff --git a/platform/ios/src/MGLMapView.h b/platform/ios/src/MGLMapView.h
index 87c24cd97b..9fe9a6c10a 100644
--- a/platform/ios/src/MGLMapView.h
+++ b/platform/ios/src/MGLMapView.h
@@ -1,9 +1,9 @@
-#import "MGLGeometry.h"
-#import "MGLMapCamera.h"
-
 #import <UIKit/UIKit.h>
 
+#import "MGLCompassButton.h"
 #import "MGLFoundation.h"
+#import "MGLGeometry.h"
+#import "MGLMapCamera.h"
 #import "MGLTypes.h"
 
 NS_ASSUME_NONNULL_BEGIN
@@ -122,7 +122,6 @@ FOUNDATION_EXTERN MGL_EXPORT const MGLMapViewPreferredFramesPerSecond MGLMapView
 
 FOUNDATION_EXTERN MGL_EXPORT MGLExceptionName const MGLMissingLocationServicesUsageDescriptionException;
 FOUNDATION_EXTERN MGL_EXPORT MGLExceptionName const MGLUserLocationAnnotationTypeException;
-FOUNDATION_EXTERN MGL_EXPORT MGLExceptionName const MGLResourceNotFoundException;
 
 /**
  An interactive, customizable map view with an interface similar to the one
@@ -316,7 +315,7 @@ MGL_EXPORT
  A control indicating the map’s direction and allowing the user to manipulate
  the direction, positioned in the upper-right corner.
  */
-@property (nonatomic, readonly) UIImageView *compassView;
+@property (nonatomic, readonly) MGLCompassButton *compassView;
 
 /**
  The position of the compass view. The default value is `MGLOrnamentPositionTopRight`.
diff --git a/platform/ios/src/MGLMapView.mm b/platform/ios/src/MGLMapView.mm
index c0b7380607..ec3766c3a0 100644
--- a/platform/ios/src/MGLMapView.mm
+++ b/platform/ios/src/MGLMapView.mm
@@ -86,7 +86,6 @@ const MGLMapViewPreferredFramesPerSecond MGLMapViewPreferredFramesPerSecondMaxim
 
 const MGLExceptionName MGLMissingLocationServicesUsageDescriptionException = @"MGLMissingLocationServicesUsageDescriptionException";
 const MGLExceptionName MGLUserLocationAnnotationTypeException = @"MGLUserLocationAnnotationTypeException";
-const MGLExceptionName MGLResourceNotFoundException = @"MGLResourceNotFoundException";
 const MGLExceptionName MGLUnderlyingMapUnavailableException = @"MGLUnderlyingMapUnavailableException";
 
 const CGPoint MGLOrnamentDefaultPositionOffset = CGPointMake(8, 8);
@@ -197,7 +196,7 @@ public:
 
 @property (nonatomic) NSMutableArray<NSLayoutConstraint *> *scaleBarConstraints;
 @property (nonatomic, readwrite) MGLScaleBar *scaleBar;
-@property (nonatomic, readwrite) UIImageView *compassView;
+@property (nonatomic, readwrite) MGLCompassButton *compassView;
 @property (nonatomic) NSMutableArray<NSLayoutConstraint *> *compassViewConstraints;
 @property (nonatomic, readwrite) UIImageView *logoView;
 @property (nonatomic) NSMutableArray<NSLayoutConstraint *> *logoViewConstraints;
@@ -308,7 +307,6 @@ public:
     BOOL _delegateHasFillColorsForShapeAnnotations;
     BOOL _delegateHasLineWidthsForShapeAnnotations;
 
-    MGLCompassDirectionFormatter *_accessibilityCompassFormatter;
     NSArray<id <MGLFeature>> *_visiblePlaceFeatures;
     NSArray<id <MGLFeature>> *_visibleRoadFeatures;
     NSMutableSet<MGLFeatureAccessibilityElement *> *_featureAccessibilityElements;
@@ -436,8 +434,6 @@ public:
 //    self.isAccessibilityElement = YES;
     self.accessibilityLabel = NSLocalizedStringWithDefaultValue(@"MAP_A11Y_LABEL", nil, nil, @"Map", @"Accessibility label");
     self.accessibilityTraits = UIAccessibilityTraitAllowsDirectInteraction | UIAccessibilityTraitAdjustable;
-    _accessibilityCompassFormatter = [[MGLCompassDirectionFormatter alloc] init];
-    _accessibilityCompassFormatter.unitStyle = NSFormattingUnitStyleLong;
     self.backgroundColor = [UIColor clearColor];
     self.clipsToBounds = YES;
     if (@available(iOS 11.0, *)) { self.accessibilityIgnoresInvertColors = YES; }
@@ -510,7 +506,7 @@ public:
 
     // setup logo
     //
-    UIImage *logo = [MGLMapView resourceImageNamed:@"mapbox"];
+    UIImage *logo = [UIImage mgl_resourceImageNamed:@"mapbox"];
     _logoView = [[UIImageView alloc] initWithImage:logo];
     _logoView.accessibilityTraits = UIAccessibilityTraitStaticText;
     _logoView.accessibilityLabel = NSLocalizedStringWithDefaultValue(@"LOGO_A11Y_LABEL", nil, nil, @"Mapbox", @"Accessibility label");
@@ -538,14 +534,8 @@ public:
 
     // setup compass
     //
-    _compassView = [[UIImageView alloc] initWithImage:self.compassImage];
-    _compassView.alpha = 0;
-    _compassView.userInteractionEnabled = YES;
+    _compassView = [MGLCompassButton compassButton];
     [_compassView addGestureRecognizer:[[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(handleCompassTapGesture:)]];
-    _compassView.accessibilityTraits = UIAccessibilityTraitButton;
-    _compassView.accessibilityLabel = NSLocalizedStringWithDefaultValue(@"COMPASS_A11Y_LABEL", nil, nil, @"Compass", @"Accessibility label");
-    _compassView.accessibilityHint = NSLocalizedStringWithDefaultValue(@"COMPASS_A11Y_HINT", nil, nil, @"Rotates the map to face due north", @"Accessibility hint");
-    _compassView.translatesAutoresizingMaskIntoConstraints = NO;
     [self addSubview:_compassView];
     _compassViewConstraints = [NSMutableArray array];
     _compassViewPosition = MGLOrnamentPositionTopRight;
@@ -664,26 +654,6 @@ public:
              static_cast<uint32_t>(size.height) };
 }
 
-- (UIImage *)compassImage
-{
-    UIImage *scaleImage = [MGLMapView resourceImageNamed:@"Compass"];
-    UIGraphicsBeginImageContextWithOptions(scaleImage.size, NO, [UIScreen mainScreen].scale);
-    [scaleImage drawInRect:{ CGPointZero, scaleImage.size }];
-
-    NSAttributedString *north = [[NSAttributedString alloc] initWithString:NSLocalizedStringWithDefaultValue(@"COMPASS_NORTH", nil, nil, @"N", @"Compass abbreviation for north") attributes:@{
-        NSFontAttributeName: [UIFont systemFontOfSize:11 weight:UIFontWeightUltraLight],
-        NSForegroundColorAttributeName: [UIColor whiteColor],
-    }];
-    CGRect stringRect = CGRectMake((scaleImage.size.width - north.size.width) / 2,
-                                   scaleImage.size.height * 0.435,
-                                   north.size.width, north.size.height);
-    [north drawInRect:stringRect];
-
-    UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
-    UIGraphicsEndImageContext();
-    return image;
-}
-
 - (void)reachabilityChanged:(NSNotification *)notification
 {
     MGLAssertIsMainThread();
@@ -4177,7 +4147,7 @@ public:
 /// rect therefore excludes the bottom half.
 - (MGLAnnotationImage *)defaultAnnotationImage
 {
-    UIImage *image = [MGLMapView resourceImageNamed:MGLDefaultStyleMarkerSymbolName];
+    UIImage *image = [UIImage mgl_resourceImageNamed:MGLDefaultStyleMarkerSymbolName];
     image = [image imageWithAlignmentRectInsets:
              UIEdgeInsetsMake(0, 0, image.size.height / 2, 0)];
     MGLAnnotationImage *annotationImage = [MGLAnnotationImage annotationImageWithImage:image
@@ -6547,35 +6517,7 @@ public:
 
 - (void)updateCompass
 {
-    CLLocationDirection direction = self.direction;
-    CLLocationDirection plateDirection = mbgl::util::wrap(-direction, 0., 360.);
-    self.compassView.transform = CGAffineTransformMakeRotation(MGLRadiansFromDegrees(plateDirection));
-
-    self.compassView.isAccessibilityElement = direction > 0;
-    self.compassView.accessibilityValue = [_accessibilityCompassFormatter stringFromDirection:direction];
-
-    if (direction > 0 && self.compassView.alpha < 1)
-    {
-        [UIView animateWithDuration:MGLAnimationDuration
-                              delay:0
-                            options:UIViewAnimationOptionBeginFromCurrentState
-                         animations:^
-                         {
-                             self.compassView.alpha = 1;
-                         }
-                         completion:nil];
-    }
-    else if (direction == 0 && self.compassView.alpha > 0)
-    {
-        [UIView animateWithDuration:MGLAnimationDuration
-                              delay:0
-                            options:UIViewAnimationOptionBeginFromCurrentState
-                         animations:^
-                         {
-                             self.compassView.alpha = 0;
-                         }
-                         completion:nil];
-    }
+    [self.compassView updateCompassWithDirection:self.direction];
 }
 
 - (void)updateScaleBar
@@ -6593,21 +6535,6 @@ public:
     }
 }
 
-+ (UIImage *)resourceImageNamed:(NSString *)imageName
-{
-    UIImage *image = [UIImage imageNamed:imageName
-                                inBundle:[NSBundle mgl_frameworkBundle]
-           compatibleWithTraitCollection:nil];
-
-    if ( ! image)
-    {
-        [NSException raise:MGLResourceNotFoundException format:
-         @"The resource named “%@” could not be found in the Mapbox framework bundle.", imageName];
-    }
-
-    return image;
-}
-
 - (BOOL)isFullyLoaded
 {
     return self.mbglMap.isFullyLoaded();
diff --git a/platform/ios/src/MGLMapView_Private.h b/platform/ios/src/MGLMapView_Private.h
index 5aa4902a91..e53dc8519c 100644
--- a/platform/ios/src/MGLMapView_Private.h
+++ b/platform/ios/src/MGLMapView_Private.h
@@ -12,6 +12,9 @@ namespace mbgl {
 class MGLMapViewImpl;
 @class MGLSource;
 
+/// Standard animation duration for UI elements.
+FOUNDATION_EXTERN const NSTimeInterval MGLAnimationDuration;
+
 /// Minimum size of an annotation’s accessibility element.
 FOUNDATION_EXTERN const CGSize MGLAnnotationAccessibilityElementMinimumSize;
 
diff --git a/platform/ios/src/Mapbox.h b/platform/ios/src/Mapbox.h
index 635bda490f..6e4e2c99fc 100644
--- a/platform/ios/src/Mapbox.h
+++ b/platform/ios/src/Mapbox.h
@@ -15,7 +15,7 @@ FOUNDATION_EXPORT MGL_EXPORT const unsigned char MapboxVersionString[];
 #import "MGLCalloutView.h"
 #import "MGLClockDirectionFormatter.h"
 #import "MGLCluster.h"
-#import "MGLCompassDirectionFormatter.h"
+#import "MGLCompassButton.h"
 #import "MGLCoordinateFormatter.h"
 #import "MGLDistanceFormatter.h"
 #import "MGLFeature.h"
diff --git a/platform/ios/src/UIImage+MGLAdditions.h b/platform/ios/src/UIImage+MGLAdditions.h
index 22bb740242..55835c50d6 100644
--- a/platform/ios/src/UIImage+MGLAdditions.h
+++ b/platform/ios/src/UIImage+MGLAdditions.h
@@ -1,9 +1,13 @@
 #import <UIKit/UIKit.h>
 
+#import <Mapbox/MGLTypes.h>
+
 #include <mbgl/style/image.hpp>
 
 NS_ASSUME_NONNULL_BEGIN
 
+FOUNDATION_EXTERN MGL_EXPORT MGLExceptionName const MGLResourceNotFoundException;
+
 @interface UIImage (MGLAdditions)
 
 - (nullable instancetype)initWithMGLStyleImage:(const mbgl::style::Image *)styleImage;
@@ -14,6 +18,8 @@ NS_ASSUME_NONNULL_BEGIN
 
 - (mbgl::PremultipliedImage)mgl_premultipliedImage;
 
++ (UIImage *)mgl_resourceImageNamed:(NSString *)imageName;
+
 @end
 
 NS_ASSUME_NONNULL_END
diff --git a/platform/ios/src/UIImage+MGLAdditions.mm b/platform/ios/src/UIImage+MGLAdditions.mm
index 884f92e003..9d05abd6ca 100644
--- a/platform/ios/src/UIImage+MGLAdditions.mm
+++ b/platform/ios/src/UIImage+MGLAdditions.mm
@@ -1,7 +1,10 @@
 #import "UIImage+MGLAdditions.h"
+#import "NSBundle+MGLAdditions.h"
 
 #include <mbgl/util/image+MGLAdditions.hpp>
 
+const MGLExceptionName MGLResourceNotFoundException = @"MGLResourceNotFoundException";
+
 @implementation UIImage (MGLAdditions)
 
 - (nullable instancetype)initWithMGLStyleImage:(const mbgl::style::Image *)styleImage
@@ -42,7 +45,20 @@
                                                 float(self.scale), isTemplate);
 }
 
--(mbgl::PremultipliedImage)mgl_premultipliedImage {
+- (mbgl::PremultipliedImage)mgl_premultipliedImage {
     return MGLPremultipliedImageFromCGImage(self.CGImage);
 }
+
++ (UIImage *)mgl_resourceImageNamed:(NSString *)imageName {
+    UIImage *image = [UIImage imageNamed:imageName
+                                inBundle:[NSBundle mgl_frameworkBundle]
+           compatibleWithTraitCollection:nil];
+
+    if (!image) {
+        [NSException raise:MGLResourceNotFoundException format:@"The resource named “%@” could not be found in the Mapbox framework bundle.", imageName];
+    }
+
+    return image;
+}
+
 @end
diff --git a/platform/ios/test/MGLCompassViewTests.m b/platform/ios/test/MGLCompassViewTests.m
new file mode 100644
index 0000000000..cabd6085a7
--- /dev/null
+++ b/platform/ios/test/MGLCompassViewTests.m
@@ -0,0 +1,23 @@
+#import <Mapbox/Mapbox.h>
+#import <XCTest/XCTest.h>
+
+@interface MGLCompassViewTests : XCTestCase
+
+@end
+
+@implementation MGLCompassViewTests
+
+- (void)setUp {
+    // Put setup code here. This method is called before the invocation of each test method in the class.
+}
+
+- (void)tearDown {
+    // Put teardown code here. This method is called after the invocation of each test method in the class.
+}
+
+- (void)testExample {
+    // This is an example of a functional test case.
+    // Use XCTAssert and related functions to verify your tests produce the correct results.
+}
+
+@end