[core] Added Map::{get,set}LatLngBounds

5 files changed, 33 insertions, 2 deletions

diff --git a/src/mbgl/map/map.cpp b/src/mbgl/map/map.cpp
index f42c11bdbb..261d2f149f 100644
--- a/src/mbgl/map/map.cpp
+++ b/src/mbgl/map/map.cpp
@@ -666,6 +666,15 @@ void Map::resetZoom() {
 
 #pragma mark - Bounds
 
+LatLngBounds Map::getLatLngBounds() const {
+    return impl->transform.getState().getLatLngBounds();
+}
+
+void Map::setLatLngBounds(const LatLngBounds& bounds) {
+    impl->cameraMutated = true;
+    impl->transform.setLatLngBounds(bounds);
+    impl->onUpdate(Update::Repaint);
+}
 
 void Map::setMinZoom(const double minZoom) {
     impl->transform.setMinZoom(minZoom);
diff --git a/src/mbgl/map/transform.cpp b/src/mbgl/map/transform.cpp
index b8c3c3fefb..469db09e0a 100644
--- a/src/mbgl/map/transform.cpp
+++ b/src/mbgl/map/transform.cpp
@@ -435,6 +435,12 @@ void Transform::setScale(double scale, optional<EdgeInsets> padding, const Anima
 
 #pragma mark - Bounds
 
+void Transform::setLatLngBounds(const LatLngBounds& bounds) {
+    if (bounds.valid()) {
+        state.setLatLngBounds(bounds);
+    }
+}
+
 void Transform::setMinZoom(const double minZoom) {
     if (std::isnan(minZoom)) return;
     state.setMinZoom(minZoom);
diff --git a/src/mbgl/map/transform.hpp b/src/mbgl/map/transform.hpp
index 4b97e07b52..a4a08f4ad9 100644
--- a/src/mbgl/map/transform.hpp
+++ b/src/mbgl/map/transform.hpp
@@ -57,6 +57,7 @@ public:
 
     // Bounds
 
+    void setLatLngBounds(const LatLngBounds&);
     void setMinZoom(double);
     void setMaxZoom(double);
 
diff --git a/src/mbgl/map/transform_state.cpp b/src/mbgl/map/transform_state.cpp
index 3336c71125..764845bc8c 100644
--- a/src/mbgl/map/transform_state.cpp
+++ b/src/mbgl/map/transform_state.cpp
@@ -142,6 +142,15 @@ double TransformState::getScale() const {
 
 #pragma mark - Bounds
 
+void TransformState::setLatLngBounds(const LatLngBounds& bounds_) {
+    bounds = bounds_;
+    setLatLngZoom(getLatLng(LatLng::Unwrapped), getZoom());
+}
+
+LatLngBounds TransformState::getLatLngBounds() const {
+    return bounds;
+}
+
 void TransformState::setMinZoom(const double minZoom) {
     if (minZoom <= getMaxZoom()) {
         min_scale = zoomScale(util::clamp(minZoom, util::MIN_ZOOM, util::MAX_ZOOM));
@@ -324,16 +333,18 @@ void TransformState::moveLatLng(const LatLng& latLng, const ScreenCoordinate& an
 }
 
 void TransformState::setLatLngZoom(const LatLng &latLng, double zoom) {
+    const LatLng constrained = bounds.constrain(latLng);
+
     double newScale = zoomScale(zoom);
     const double newWorldSize = newScale * util::tileSize;
     Bc = newWorldSize / util::DEGREES_MAX;
     Cc = newWorldSize / util::M2PI;
 
     const double m = 1 - 1e-15;
-    const double f = util::clamp(std::sin(util::DEG2RAD * latLng.latitude()), -m, m);
+    const double f = util::clamp(std::sin(util::DEG2RAD * constrained.latitude()), -m, m);
 
     ScreenCoordinate point = {
-        -latLng.longitude() * Bc,
+        -constrained.longitude() * Bc,
         0.5 * Cc * std::log((1 + f) / (1 - f)),
     };
     setScalePoint(newScale, point);
diff --git a/src/mbgl/map/transform_state.hpp b/src/mbgl/map/transform_state.hpp
index 4a0218e10e..b8baefdba1 100644
--- a/src/mbgl/map/transform_state.hpp
+++ b/src/mbgl/map/transform_state.hpp
@@ -51,6 +51,8 @@ public:
     double getZoomFraction() const;
 
     // Bounds
+    void setLatLngBounds(const LatLngBounds&);
+    LatLngBounds getLatLngBounds() const;
     void setMinZoom(double);
     double getMinZoom() const;
     void setMaxZoom(double);
@@ -84,6 +86,8 @@ private:
     bool rotatedNorth() const;
     void constrain(double& scale, double& x, double& y) const;
 
+    LatLngBounds bounds = LatLngBounds::world();
+
     // Limit the amount of zooming possible on the map.
     double min_scale = std::pow(2, 0);
     double max_scale = std::pow(2, 20);