[core] Added Viewport mode

Satisfies embedding platforms that requires the viewport coordinate
systems to be set according to its standards e.g. viewport mirrored
vertically.

1 files changed, 12 insertions, 2 deletions

diff --git a/src/mbgl/map/transform.cpp b/src/mbgl/map/transform.cpp
index 69a644c7d9..958f9d9b63 100644
--- a/src/mbgl/map/transform.cpp
+++ b/src/mbgl/map/transform.cpp
@@ -36,9 +36,9 @@ static double _normalizeAngle(double angle, double anchorAngle)
     return angle;
 }
 
-Transform::Transform(View &view_, ConstrainMode constrainMode)
+Transform::Transform(View &view_, ConstrainMode constrainMode, ViewportMode viewportMode)
     : view(view_)
-    , state(constrainMode)
+    , state(constrainMode, viewportMode)
 {
 }
 
@@ -555,6 +555,16 @@ ConstrainMode Transform::getConstrainMode() const {
     return state.getConstrainMode();
 }
 
+#pragma mark - Viewport mode
+
+void Transform::setViewportMode(mbgl::ViewportMode mode) {
+    state.viewportMode = mode;
+}
+
+ViewportMode Transform::getViewportMode() const {
+    return state.getViewportMode();
+}
+
 #pragma mark - Transition
 
 void Transform::startTransition(const CameraOptions& camera,