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authorJohn Firebaugh <john.firebaugh@gmail.com>2016-02-11 12:21:49 -0800
committerJohn Firebaugh <john.firebaugh@gmail.com>2016-02-12 14:53:52 -0800
commit13e2acbc754893efb945fe02d20824698415dcdb (patch)
treee8e4c966f03798fc6896a0fd3163e83921f84a38 /platform/darwin/src/MGLGeometry.mm
parentab677a7905b0f81850d6aa3dcdd2caebc0dbc851 (diff)
downloadqtlocation-mapboxgl-13e2acbc754893efb945fe02d20824698415dcdb.tar.gz
[ios, osx] Consolidate remaining files in platform/{ios,osx}
Diffstat (limited to 'platform/darwin/src/MGLGeometry.mm')
-rw-r--r--platform/darwin/src/MGLGeometry.mm46
1 files changed, 46 insertions, 0 deletions
diff --git a/platform/darwin/src/MGLGeometry.mm b/platform/darwin/src/MGLGeometry.mm
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+#import "MGLGeometry_Private.h"
+
+#import <mbgl/util/projection.hpp>
+
+/** Vertical field of view, measured in degrees, for determining the altitude
+ of the viewpoint.
+
+ TransformState::getProjMatrix() assumes a vertical field of view of
+ 2 arctan ⅓ rad ≈ 36.9°, but MapKit uses a vertical field of view of 30°.
+ flyTo() assumes a field of view of 2 arctan ½ rad. */
+const CLLocationDegrees MGLAngularFieldOfView = 30;
+
+const MGLCoordinateSpan MGLCoordinateSpanZero = {0, 0};
+
+CGRect MGLExtendRect(CGRect rect, CGPoint point) {
+ if (point.x < rect.origin.x) {
+ rect.size.width += rect.origin.x - point.x;
+ rect.origin.x = point.x;
+ }
+ if (point.x > rect.origin.x + rect.size.width) {
+ rect.size.width += point.x - (rect.origin.x + rect.size.width);
+ }
+ if (point.y < rect.origin.y) {
+ rect.size.height += rect.origin.y - point.y;
+ rect.origin.y = point.y;
+ }
+ if (point.y > rect.origin.y + rect.size.height) {
+ rect.size.height += point.y - (rect.origin.y + rect.size.height);
+ }
+ return rect;
+}
+
+CLLocationDistance MGLAltitudeForZoomLevel(double zoomLevel, CGFloat pitch, CLLocationDegrees latitude, CGSize size) {
+ CLLocationDistance metersPerPixel = mbgl::Projection::getMetersPerPixelAtLatitude(latitude, zoomLevel);
+ CLLocationDistance metersTall = metersPerPixel * size.height;
+ CLLocationDistance altitude = metersTall / 2 / std::tan(MGLRadiansFromDegrees(MGLAngularFieldOfView) / 2.);
+ return altitude * std::sin(M_PI_2 - MGLRadiansFromDegrees(pitch)) / std::sin(M_PI_2);
+}
+
+double MGLZoomLevelForAltitude(CLLocationDistance altitude, CGFloat pitch, CLLocationDegrees latitude, CGSize size) {
+ CLLocationDistance eyeAltitude = altitude / std::sin(M_PI_2 - MGLRadiansFromDegrees(pitch)) * std::sin(M_PI_2);
+ CLLocationDistance metersTall = eyeAltitude * 2 * std::tan(MGLRadiansFromDegrees(MGLAngularFieldOfView) / 2.);
+ CLLocationDistance metersPerPixel = metersTall / size.height;
+ CGFloat mapPixelWidthAtZoom = std::cos(MGLRadiansFromDegrees(latitude)) * mbgl::util::M2PI * mbgl::util::EARTH_RADIUS_M / metersPerPixel;
+ return ::log2(mapPixelWidthAtZoom / mbgl::util::tileSize);
+}