1 files changed, 2 insertions, 1 deletions
diff --git a/src/Fl_Gl_Window_Driver.H b/src/Fl_Gl_Window_Driver.H
index ddc52c794..10cd3f11b 100644
--- a/src/Fl_Gl_Window_Driver.H
+++ b/src/Fl_Gl_Window_Driver.H
@@ -96,7 +96,8 @@ public:
   virtual int overlay_color(Fl_Color i) {return 0;} // support for gl_color() with HAVE_GL_OVERLAY
   static void draw_string_with_texture(const char* str, int n); // cross-platform
   // support for gl_draw(). The cross-platform version may be enough.
-  virtual char *alpha_mask_for_string(const char *str, int n, int w, int h);
+  virtual char *alpha_mask_for_string(const char *str, int n, int w, int h, Fl_Fontsize fs);
+  virtual Fl_Fontsize effective_size();
   virtual int genlistsize() { return 0; } // support for gl_draw()
   virtual Fl_Font_Descriptor** fontnum_to_fontdescriptor(int fnum);
   virtual Fl_RGB_Image* capture_gl_rectangle(int x, int y, int w, int h);