[core] make padding optional when camera position is requested.

When padding is not provided, the current one that's cached in the TransformState is going to be returned.

include/mbgl/map/map.hpp

@@ -60,7 +60,7 @@ public:
     bool isPanning() const;
 
     // Camera
-    CameraOptions getCameraOptions(const EdgeInsets& = {}) const;
+    CameraOptions getCameraOptions(optional<EdgeInsets> = {}) const;
     void jumpTo(const CameraOptions&);
     void easeTo(const CameraOptions&, const AnimationOptions&);
     void flyTo(const CameraOptions&, const AnimationOptions&);

src/mbgl/map/map.cpp

@@ -124,7 +124,7 @@ bool Map::isPanning() const {
 
 #pragma mark -
 
-CameraOptions Map::getCameraOptions(const EdgeInsets& padding) const {
+CameraOptions Map::getCameraOptions(optional<EdgeInsets> padding) const {
     return impl->transform.getCameraOptions(padding);
 }
 

src/mbgl/map/transform.cpp

@@ -63,7 +63,7 @@ void Transform::resize(const Size size) {
 
 #pragma mark - Camera
 
-CameraOptions Transform::getCameraOptions(const EdgeInsets& padding) const {
+CameraOptions Transform::getCameraOptions(optional<EdgeInsets> padding) const {
     return state.getCameraOptions(padding);
 }
 

src/mbgl/map/transform.hpp

@@ -29,7 +29,7 @@ public:
 
     // Camera
     /** Returns the current camera options. */
-    CameraOptions getCameraOptions(const EdgeInsets&) const;
+    CameraOptions getCameraOptions(optional<EdgeInsets>) const;
 
     /** Instantaneously, synchronously applies the given camera options. */
     void jumpTo(const CameraOptions&);

src/mbgl/map/transform_state.cpp

@@ -146,10 +146,10 @@ ViewportMode TransformState::getViewportMode() const {
 
 #pragma mark - Camera options
 
-CameraOptions TransformState::getCameraOptions(const EdgeInsets& padding) const {
+CameraOptions TransformState::getCameraOptions(optional<EdgeInsets> padding) const {
     return CameraOptions()
         .withCenter(getLatLng())
-        .withPadding(padding)
+        .withPadding(padding ? padding : edgeInsets)
         .withZoom(getZoom())
         .withBearing(-bearing * util::RAD2DEG)
         .withPitch(pitch * util::RAD2DEG);

src/mbgl/map/transform_state.hpp

@@ -43,7 +43,7 @@ public:
     // Viewport mode
     ViewportMode getViewportMode() const;
 
-    CameraOptions getCameraOptions(const EdgeInsets&) const;
+    CameraOptions getCameraOptions(optional<EdgeInsets>) const;
 
     // Position
     LatLng getLatLng(LatLng::WrapMode = LatLng::Unwrapped) const;