[core] Added GLContextMode to MapData

Adding new mbgl::GLContextMode enum to mbgl::Map ctor, which gets stored
in MapData. In shared GL context environments, we cannot assume that the
GL state that has been left since the last draw is the same, so we reset
the GL configurations to their default values.

2 files changed, 9 insertions, 3 deletions

diff --git a/include/mbgl/map/map.hpp b/include/mbgl/map/map.hpp
index 9661bcc7bc..65f988b5bf 100644
--- a/include/mbgl/map/map.hpp
+++ b/include/mbgl/map/map.hpp
@@ -44,7 +44,8 @@ class Map : private util::noncopyable {
 
 public:
     explicit Map(View&, FileSource&,
-                 MapMode mode = MapMode::Continuous);
+                 MapMode mapMode = MapMode::Continuous,
+                 GLContextMode contextMode = GLContextMode::Unique);
     ~Map();
 
     // Pauses the render thread. The render thread will stop running but will not be terminated and will not lose state until resumed.
diff --git a/include/mbgl/map/mode.hpp b/include/mbgl/map/mode.hpp
index 4ade870d90..3e838dca99 100644
--- a/include/mbgl/map/mode.hpp
+++ b/include/mbgl/map/mode.hpp
@@ -10,6 +10,11 @@ enum class MapMode : uint8_t {
     Still, // a once-off still image
 };
 
-}
+enum class GLContextMode : uint8_t {
+    Unique,
+    Shared,
+};
+
+} // namespace mbgl
 
-#endif
\ No newline at end of file
+#endif // MBGL_MAP_MODE