[ios, macos] Fixed camera initialization with eye coordinateupstream/1ec5-camera-distance-12943

Rewrote the code that calculates the heading and pitch of the camera when given an eye coordinate.

2 files changed, 50 insertions, 11 deletions

diff --git a/platform/darwin/src/MGLMapCamera.mm b/platform/darwin/src/MGLMapCamera.mm
index 968b64ad17..62f7931641 100644
--- a/platform/darwin/src/MGLMapCamera.mm
+++ b/platform/darwin/src/MGLMapCamera.mm
@@ -1,7 +1,9 @@
 #import "MGLMapCamera.h"
 #import "MGLGeometry_Private.h"
 
-#include <mbgl/util/projection.hpp>
+#import <CoreLocation/CoreLocation.h>
+
+#include <mbgl/math/wrap.hpp>
 
 BOOL MGLEqualFloatWithAccuracy(CGFloat left, CGFloat right, CGFloat accuracy)
 {
@@ -27,17 +29,15 @@ BOOL MGLEqualFloatWithAccuracy(CGFloat left, CGFloat right, CGFloat accuracy)
     CLLocationDirection heading = -1;
     CGFloat pitch = -1;
     if (CLLocationCoordinate2DIsValid(centerCoordinate) && CLLocationCoordinate2DIsValid(eyeCoordinate)) {
-        mbgl::LatLng centerLatLng = MGLLatLngFromLocationCoordinate2D(centerCoordinate);
-        mbgl::LatLng eyeLatLng = MGLLatLngFromLocationCoordinate2D(eyeCoordinate);
-        
-        mbgl::ProjectedMeters centerMeters = mbgl::Projection::projectedMetersForLatLng(centerLatLng);
-        mbgl::ProjectedMeters eyeMeters = mbgl::Projection::projectedMetersForLatLng(eyeLatLng);
-        heading = std::atan((centerMeters.northing() - eyeMeters.northing()) /
-                            (centerMeters.easting() - eyeMeters.easting()));
+        heading = MGLDirectionBetweenCoordinates(eyeCoordinate, centerCoordinate);
         
-        double groundDistance = std::hypot(centerMeters.northing() - eyeMeters.northing(),
-                                           centerMeters.easting() - eyeMeters.easting());
-        pitch = std::atan(eyeAltitude / groundDistance);
+        CLLocation *centerLocation = [[CLLocation alloc] initWithLatitude:centerCoordinate.latitude
+                                                                longitude:centerCoordinate.longitude];
+        CLLocation *eyeLocation = [[CLLocation alloc] initWithLatitude:eyeCoordinate.latitude
+                                                             longitude:eyeCoordinate.longitude];
+        CLLocationDistance groundDistance = [eyeLocation distanceFromLocation:centerLocation];
+        CGFloat radianPitch = atan2(eyeAltitude, groundDistance);
+        pitch = mbgl::util::wrap(90 - MGLDegreesFromRadians(radianPitch), 0.0, 360.0);
     }
 
     return [[self alloc] initWithCenterCoordinate:centerCoordinate
diff --git a/platform/darwin/test/MGLMapCameraTests.m b/platform/darwin/test/MGLMapCameraTests.m
index 9c3a9a526c..9fbf6b9e45 100644
--- a/platform/darwin/test/MGLMapCameraTests.m
+++ b/platform/darwin/test/MGLMapCameraTests.m
@@ -9,6 +9,45 @@
 
 @implementation MGLMapCameraTests
 
+- (void)testEyeCoordinateInitialization {
+    CLLocationCoordinate2D fountainSquare = CLLocationCoordinate2DMake(39.10152215, -84.5124439696089);
+    CLLocationCoordinate2D unionTerminal = CLLocationCoordinate2DMake(39.10980955, -84.5352778794236);
+    
+    MGLMapCamera *camera = [MGLMapCamera cameraLookingAtCenterCoordinate:fountainSquare
+                                                       fromEyeCoordinate:fountainSquare
+                                                             eyeAltitude:1000];
+    MKMapCamera *mkCamera = [MKMapCamera cameraLookingAtCenterCoordinate:fountainSquare
+                                                       fromEyeCoordinate:fountainSquare
+                                                             eyeAltitude:1000];
+    XCTAssertEqual(camera.centerCoordinate.latitude, fountainSquare.latitude);
+    XCTAssertEqual(camera.centerCoordinate.longitude, fountainSquare.longitude);
+    XCTAssertEqual(camera.centerCoordinate.latitude, mkCamera.centerCoordinate.latitude);
+    XCTAssertEqual(camera.centerCoordinate.longitude, mkCamera.centerCoordinate.longitude);
+    XCTAssertEqual(camera.altitude, 1000, @"Eye altitude should be equivalent to altitude in untilted camera.");
+    XCTAssertEqual(camera.altitude, mkCamera.altitude, @"Eye altitude in untilted camera should match MapKit.");
+    XCTAssertEqual(camera.pitch, 0, @"Camera directly over center coordinate should be untilted.");
+    XCTAssertEqual(camera.pitch, mkCamera.pitch, @"Camera directly over center coordinate should have same pitch as MapKit.");
+    XCTAssertEqual(camera.heading, 0, @"Camera directly over center coordinate should be unrotated.");
+    XCTAssertEqual(camera.heading, mkCamera.heading, @"Camera directly over center coordinate should have same heading as MapKit.");
+    
+    camera = [MGLMapCamera cameraLookingAtCenterCoordinate:fountainSquare
+                                         fromEyeCoordinate:unionTerminal
+                                               eyeAltitude:1000];
+    mkCamera = [MKMapCamera cameraLookingAtCenterCoordinate:fountainSquare
+                                          fromEyeCoordinate:unionTerminal
+                                                eyeAltitude:1000];
+    XCTAssertEqual(camera.centerCoordinate.latitude, fountainSquare.latitude);
+    XCTAssertEqual(camera.centerCoordinate.longitude, fountainSquare.longitude);
+    XCTAssertEqual(camera.centerCoordinate.latitude, mkCamera.centerCoordinate.latitude);
+    XCTAssertEqual(camera.centerCoordinate.longitude, mkCamera.centerCoordinate.longitude);
+    XCTAssertEqual(camera.altitude, 1000);
+    XCTAssertEqual(camera.altitude, mkCamera.altitude, @"Eye altitude in tilted camera should match MapKit.");
+    XCTAssertEqualWithAccuracy(camera.pitch, 65.3469146074, 0.01);
+    XCTAssertEqual(camera.pitch, mkCamera.pitch);
+    XCTAssertEqualWithAccuracy(camera.heading, 115.066396383, 0.01);
+    XCTAssertEqualWithAccuracy(camera.heading, mkCamera.heading, 0.01);
+}
+
 - (void)testViewingDistanceInitialization {
     CLLocationCoordinate2D fountainSquare = CLLocationCoordinate2DMake(39.10152215, -84.5124439696089);
     MGLMapCamera *camera = [MGLMapCamera cameraLookingAtCenterCoordinate:fountainSquare