Replace compile-time polymorphism with runtime polymorphism in the conversion system

1 files changed, 29 insertions, 0 deletions

diff --git a/src/mbgl/style/conversion/coordinate.cpp b/src/mbgl/style/conversion/coordinate.cpp
new file mode 100644
index 0000000000..9b2be3381e
--- /dev/null
+++ b/src/mbgl/style/conversion/coordinate.cpp
@@ -0,0 +1,29 @@
+#include <mbgl/style/conversion/coordinate.hpp>
+
+namespace mbgl {
+namespace style {
+namespace conversion {
+
+optional<LatLng> Converter<LatLng>::operator() (const Convertible& value, Error& error) const {
+    if (!isArray(value) || arrayLength(value) < 2 ) {
+        error = { "coordinate array must contain numeric longitude and latitude values" };
+        return {};
+    }
+    //Style spec uses GeoJSON convention for specifying coordinates
+    optional<double> latitude = toDouble(arrayMember(value, 1));
+    optional<double> longitude = toDouble(arrayMember(value, 0));
+
+    if (!latitude || !longitude) {
+        error = { "coordinate array must contain numeric longitude and latitude values" };
+        return {};
+    }
+    if (*latitude < -90 || *latitude > 90 ){
+        error = { "coordinate latitude must be between -90 and 90" };
+        return {};
+    }
+    return LatLng(*latitude, *longitude);
+}
+
+} // namespace conversion
+} // namespace style
+} // namespace mbgl