App::I static singleton to pointer

src/font.cpp

@@ -60,7 +60,7 @@ const Font& FontManager::get(kFont id)
 
 bool TextMesh::create()
 {
-    App::I.render_task([this]
+    App::I->render_task([this]
     {
         glGenBuffers(2, font_buffers);
 #if USE_VBO
@@ -125,7 +125,7 @@ void TextMesh::update(kFont id, const char* text)
             vi -= glm::vec4(bbmin, 0, 0);
         bb = bbmax - bbmin;
         font_array_count = (int)idx.size();
-        App::I.render_task([&]
+        App::I->render_task([&]
         {
             glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, font_buffers[1]);
             glBufferData(GL_ELEMENT_ARRAY_BUFFER, idx.size() * sizeof(GLushort), idx.data(), GL_STATIC_DRAW);