Unify OpenGL ES support

src/client/renderingengine.cpp

@@ -48,7 +48,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 
 #endif
 
-#ifdef __ANDROID__
+#if ENABLE_GLES
 #include "filesys.h"
 #endif
 
@@ -131,6 +131,11 @@ RenderingEngine::RenderingEngine(IEventReceiver *receiver)
 	params.OGLES2ShaderPath = std::string(porting::path_user + DIR_DELIM + "media" +
 		DIR_DELIM + "Shaders" + DIR_DELIM).c_str();
 	// clang-format on
+#elif ENABLE_GLES
+	// there is no standardized path for these on desktop
+	std::string rel_path = std::string("client") + DIR_DELIM
+			+ "shaders" + DIR_DELIM + "Irrlicht";
+	params.OGLES2ShaderPath = (porting::path_share + DIR_DELIM + rel_path + DIR_DELIM).c_str();
 #endif
 
 	m_device = createDeviceEx(params);