diff --git a/rts/Lua/LuaContextData.h b/rts/Lua/LuaContextData.h
index ee3d78c4f8d..9c14354021b 100644
--- a/rts/Lua/LuaContextData.h
+++ b/rts/Lua/LuaContextData.h
@@ -49,7 +49,7 @@ struct GLMatrixStateTracker {
 		return matrixData.mode;
 	}
 
-	int &GetDepth(unsigned int mode) {
+	int& GetDepth(unsigned int mode) {
 		switch (mode) {
 			case GL_MODELVIEW: return matrixData.modelView;
 			case GL_PROJECTION: return matrixData.projection;
@@ -63,7 +63,7 @@ struct GLMatrixStateTracker {
 
 	bool PushMatrix() {
 		unsigned int mode = GetMode();
-		int &depth = GetDepth(mode);
+		int& depth = GetDepth(mode);
 		if (!listMode && depth >= 255)
 			return false;
 		depth += 1;
@@ -72,7 +72,7 @@ struct GLMatrixStateTracker {
 
 	bool PopMatrix() {
 		unsigned int mode = GetMode();
-		int &depth = GetDepth(mode);
+		int& depth = GetDepth(mode);
 		if (listMode) {
 			depth -= 1;
 			return true;
@@ -165,6 +165,7 @@ struct GLMatrixStateTracker {
 
 
 struct luaContextData {
+public:
 	luaContextData()
 	: owner(nullptr)
 	, luamutex(nullptr)
@@ -184,6 +185,15 @@ struct luaContextData {
 	, selectTeam(CEventClient::NoAccessTeam)
 	, parser(nullptr) {}
 
+	void Clear() {
+		shaders.Clear();
+		textures.Clear();
+		fbos.Clear();
+		rbos.Clear();
+		displayLists.Clear();
+	}
+
+public:
 	CLuaHandle* owner;
 	spring::recursive_mutex* luamutex;
 
diff --git a/rts/Lua/LuaDisplayLists.h b/rts/Lua/LuaDisplayLists.h
index 7619934d5b6..bec898c5f44 100644
--- a/rts/Lua/LuaDisplayLists.h
+++ b/rts/Lua/LuaDisplayLists.h
@@ -20,21 +20,20 @@ struct SMatrixStateData {
 
 class CLuaDisplayLists {
 	public:
-		CLuaDisplayLists()
-		{
-			active.push_back(DLdata(0));
-		}
-		
+		CLuaDisplayLists() { Clear(); }
 		~CLuaDisplayLists()
 		{
 			// free the display lists
-			for (int i = 0; i < (int)active.size(); i++) {
+			// NOTE:
+			//   it is not an error to delete a list with id=0, but we might
+			//   be called from ~LuaParser which can run in multiple threads
+			//   and the null-list is always present (even after Clear())
+			for (size_t i = 1; i < active.size(); i++) {
 				glDeleteLists(active[i].id, 1);
 			}
 		}
 
-		void Clear()
-		{
+		void Clear() {
 			unused.clear();
 			active.clear();
 			active.push_back(DLdata(0));
@@ -44,27 +43,25 @@ class CLuaDisplayLists {
 		
 		GLuint GetDList(unsigned int index) const
 		{
-			if (index < active.size()) {
+			if (index < active.size())
 				return active[index].id;
-			} else {
-				return 0;
-			}
+
+			return 0;
 		}
 
 		SMatrixStateData GetMatrixState(unsigned int index) const
 		{
-			if (index < active.size()) {
+			if (index < active.size())
 				return active[index].matData;
-			} else {
-				return SMatrixStateData();
-			}
+
+			return SMatrixStateData();
 		}
 
 		unsigned int NewDList(GLuint dlist, SMatrixStateData& m)
 		{
-			if (dlist == 0) {
+			if (dlist == 0)
 				return 0;
-			}
+
 			if (!unused.empty()) {
 				const unsigned int index = unused[unused.size() - 1];
 				active[index] = DLdata(dlist, m);
diff --git a/rts/Lua/LuaFBOs.h b/rts/Lua/LuaFBOs.h
index 16d84889801..32857c3bea6 100644
--- a/rts/Lua/LuaFBOs.h
+++ b/rts/Lua/LuaFBOs.h
@@ -16,6 +16,8 @@ class LuaFBOs {
 	LuaFBOs() { fbos.reserve(8); }
 	~LuaFBOs();
 
+	void Clear() { fbos.clear(); }
+
 	struct FBO {
 		void Init(lua_State* L);
 		void Free(lua_State* L);
diff --git a/rts/Lua/LuaParser.cpp b/rts/Lua/LuaParser.cpp
index 73f6013276b..3be79f408c9 100644
--- a/rts/Lua/LuaParser.cpp
+++ b/rts/Lua/LuaParser.cpp
@@ -85,6 +85,10 @@ LuaParser::LuaParser(const string& _textChunk, const string& _accessModes, const
 
 LuaParser::~LuaParser()
 {
+	// prevent crashes in glDelete* calls since LuaParser
+	// might be constructed by multiple different threads
+	D.Clear();
+
 	if (L != nullptr)
 		LUA_CLOSE(&L);
 
diff --git a/rts/Lua/LuaRBOs.h b/rts/Lua/LuaRBOs.h
index 2fb04e3a817..fe96fe7265f 100644
--- a/rts/Lua/LuaRBOs.h
+++ b/rts/Lua/LuaRBOs.h
@@ -16,6 +16,8 @@ class LuaRBOs {
 		LuaRBOs() { rbos.reserve(8); }
 		~LuaRBOs();
 
+		void Clear() { rbos.clear(); }
+
 		static bool PushEntries(lua_State* L);
 
 		struct RBO;
diff --git a/rts/Lua/LuaShaders.h b/rts/Lua/LuaShaders.h
index 510d9a4eed6..5c8463eee0e 100644
--- a/rts/Lua/LuaShaders.h
+++ b/rts/Lua/LuaShaders.h
@@ -19,6 +19,11 @@ class LuaShaders {
 		LuaShaders();
 		~LuaShaders();
 
+		void Clear() {
+			programs.clear();
+			unused.clear();
+		}
+
 		std::string errorLog;
 
 		GLuint GetProgramName(unsigned int progIdx) const;
diff --git a/rts/Lua/LuaTextures.h b/rts/Lua/LuaTextures.h
index 07ed33e36f2..d000a7f18ba 100644
--- a/rts/Lua/LuaTextures.h
+++ b/rts/Lua/LuaTextures.h
@@ -21,6 +21,12 @@ class LuaTextures {
 		lastCode = 0;
 	}
 
+	void Clear() {
+		textureVec.clear();
+		textureMap.clear();
+		freeIndices.clear();
+	}
+
 	struct Texture {
 		Texture()
 		: name(""), id(0), fbo(0), fboDepth(0),