1 files changed, 47 insertions, 0 deletions
diff --git a/src/mbgl/util/tile_range.hpp b/src/mbgl/util/tile_range.hpp
new file mode 100644
index 0000000000..f630a49078
--- /dev/null
+++ b/src/mbgl/util/tile_range.hpp
@@ -0,0 +1,47 @@
+#pragma once
+
+#include <mbgl/tile/tile_id.hpp>
+#include <mbgl/util/range.hpp>
+#include <mbgl/util/geo.hpp>
+#include <mbgl/util/projection.hpp>
+
+namespace mbgl {
+
+namespace util {
+
+class TileRange {
+public:
+    Range<Point<double>> range;
+    uint8_t z;
+
+    // Compute the range of tiles covered by the bounds.
+    static TileRange fromLatLngBounds(const LatLngBounds& bounds, uint8_t z) {
+        auto swProj = Projection::project(bounds.southwest().wrapped(), z);
+        auto ne = bounds.northeast();
+        auto neProj = Projection::project(ne.longitude() > util::LONGITUDE_MAX ? ne.wrapped() : ne , z);
+        const auto minX = std::floor(swProj.x);
+        const auto maxX = std::ceil(neProj.x);
+        const auto minY = std::floor(neProj.y);
+        const auto maxY = std::ceil(swProj.y);
+        return TileRange({ {minX, minY}, {maxX, maxY} }, z);
+    }
+
+    bool contains(const CanonicalTileID& tileID) {
+        return z == tileID.z &&
+        (range.min.x >= range.max.x ? //For wrapped bounds
+            tileID.x >= range.min.x || tileID.x < range.max.x :
+            tileID.x < range.max.x && tileID.x >= range.min.x) &&
+        tileID.y < range.max.y &&
+        tileID.y >= range.min.y;
+    }
+
+private:
+    TileRange(Range<Point<double>> range_, uint8_t z_)
+     : range(range_),
+     z(z_) {
+    }
+    
+};
+
+} // namespace util
+} // namespace mbgl