diff --git a/ftgl_testing.cc b/ftgl_testing.cc
index 7080293..5a7f9b3 100644
--- a/ftgl_testing.cc
+++ b/ftgl_testing.cc
@@ -40,17 +40,18 @@ void display(SDL_Window * window)
         glVertex3f(10.0, 210.0, 0.0);
         glVertex3f(10.0, 202.0, 0.0);
     glEnd();
-    font->Render("abcdefghijklmnopqrstuvwxyz", -1, FTPoint(10, HEIGHT - FONT_SIZE, 0));
-    font->Render("ABCDEFGHIJKLMNOPQRSTUVWXYZ", -1, FTPoint(10, HEIGHT - FONT_SIZE * 2, 0));
+    float line_height = font->LineHeight();
+    font->Render("abcdefghijklmnopqrstuvwxyz", -1, FTPoint(10, HEIGHT - line_height, 0));
+    font->Render("ABCDEFGHIJKLMNOPQRSTUVWXYZ", -1, FTPoint(10, HEIGHT - line_height * 2, 0));
     for (int i = 0; i < 26; i++)
     {
         char s[2];
         s[0] = 'A' + i;
         s[1] = '\0';
         float advance = font->Advance("M");
-        font->Render(s, -1, FTPoint(10 + advance * i, HEIGHT - FONT_SIZE * 3, 0));
+        font->Render(s, -1, FTPoint(10 + advance * i, HEIGHT - line_height * 3, 0));
     }
-    font->Render("0123456789", -1, FTPoint(10, HEIGHT - FONT_SIZE * 4, 0));
+    font->Render("0123456789", -1, FTPoint(10, HEIGHT - line_height * 4, 0));
     SDL_GL_SwapWindow(window);
 }