Fix access for entity and scene, as they are needed by the implementation code.

engine/engine.xcodeproj/project.pbxproj

@@ -13,12 +13,12 @@
 		CD62D8482251A9500023219A /* libmath.dylib in Frameworks */ = {isa = PBXBuildFile; fileRef = CD62D8472251A9500023219A /* libmath.dylib */; };
 		CD62FCCE22904A8900376440 /* libengine.dylib in Frameworks */ = {isa = PBXBuildFile; fileRef = CDB1F8AE1D7A30CD00700C6B /* libengine.dylib */; };
 		CD62FCD622904A9B00376440 /* GoogleMock.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = CD62FCBE22904A7C00376440 /* GoogleMock.framework */; };
-		CD62FD35229364DB00376440 /* entity.cxx in Sources */ = {isa = PBXBuildFile; fileRef = CD62FD33229364DB00376440 /* entity.cxx */; };
+		CD62FD35229364DB00376440 /* entity.cxx in Sources */ = {isa = PBXBuildFile; fileRef = CD62FD33229364DB00376440 /* entity.cxx */; settings = {COMPILER_FLAGS = "-fvisibility=default"; }; };
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 		CD62FD402293746900376440 /* serial.cxx in Sources */ = {isa = PBXBuildFile; fileRef = CD62FD3E2293746900376440 /* serial.cxx */; settings = {COMPILER_FLAGS = "-fvisibility=default"; }; };
 		CD7E87792295FAB400D877FE /* libgameutils.dylib in Frameworks */ = {isa = PBXBuildFile; fileRef = CD7E87782295FAB400D877FE /* libgameutils.dylib */; };
 		CDB1F8C81D7A312B00700C6B /* game_dispatch.cpp in Sources */ = {isa = PBXBuildFile; fileRef = CDB1F8C61D7A312B00700C6B /* game_dispatch.cpp */; settings = {COMPILER_FLAGS = "-fvisibility=default"; }; };
-		CDB1F8CC1D7A319A00700C6B /* scene.cpp in Sources */ = {isa = PBXBuildFile; fileRef = CDB1F8CA1D7A319A00700C6B /* scene.cpp */; };
+		CDB1F8CC1D7A319A00700C6B /* scene.cpp in Sources */ = {isa = PBXBuildFile; fileRef = CDB1F8CA1D7A319A00700C6B /* scene.cpp */; settings = {COMPILER_FLAGS = "-fvisibility=default"; }; };
 		CDB1F8D21D7A32A300700C6B /* events.cpp in Sources */ = {isa = PBXBuildFile; fileRef = CDB1F8D01D7A32A300700C6B /* events.cpp */; settings = {COMPILER_FLAGS = "-fvisibility=default"; }; };
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