#2: Font API requires asset manager.

include/Zenderer/GUI/Font.hpp

@@ -127,12 +127,16 @@ namespace gui
         /// Clears the internal string stream.
         void ClearString();
 
-        void AttachManager(asset::CAssetManager& Assets);
+        void AttachManager(asset::CAssetManager& Assets)
+        {
+            mp_Assets = &Assets;
+        }
 
     private:
         bool Destroy();
         bool LoadGlyph(const char c, const uint32_t index);
 
+        asset::CAssetManager* mp_Assets;
         color4f_t m_Color;
         FT_Face m_FontFace;
 
@@ -156,6 +160,11 @@ namespace gui
  *  themselves into `obj::CEntity` instances that can then be treated as
  *  such. 
  *
+ * @note    It is absolutely essential that you call `AttachManager()` prior
+ *          to loading any font instances, to ensure that the font textures
+ *          can be created. This is a limitation of the asset API and may or
+ *          may not change in the future. 
+ *
  * @example Fonts
  * @section Font Rendering Examples
  * @subsection Rendering With a Scene
@@ -172,6 +181,9 @@ namespace gui
  *
  *  // Error checking omitted for brevity.
  *
+ *  // REQUIRED!
+ *  Font->AttachManager(Assets);
+ *
  *  // Render a string to an entity
  *  obj::CEntity& Score = Scene.AddEntity();
  *  Font->Render(Score, "Score: 0");

src/GUI/Font.cpp

@@ -236,6 +236,7 @@ void CFont::ClearString()
 
 bool CFont::LoadGlyph(const char c, const uint32_t index)
 {
+    ZEN_ASSERTM(mp_Assets != nullptr, "an asset manager must be attached");
     FT_Glyph g;
 
     // Render as a monochrome bitmap into glyph struct.
@@ -259,7 +260,7 @@ bool CFont::LoadGlyph(const char c, const uint32_t index)
     GL(glGetIntegerv(GL_UNPACK_ALIGNMENT, &pack));
     GL(glPixelStorei(GL_UNPACK_ALIGNMENT, 1))
 
-    gfxcore::CTexture* pTexture = m_Assets.Create<gfxcore::CTexture>(this->GetOwner());
+    gfxcore::CTexture* pTexture = mp_Assets->Create<gfxcore::CTexture>(this->GetOwner());
     pTexture->LoadFromRaw(GL_R8, GL_RED, w, h, bitmap.buffer);
 
     GL(glPixelStorei(GL_UNPACK_ALIGNMENT, pack));