Handle missing glyphs

Author: tannewt

.gitignore

@@ -0,0 +1,2 @@
+__pycache__
+

adafruit_bitmap_font/bdf.py

@@ -85,7 +85,7 @@ def load_glyphs(self, code_points):
                 code_point = int(code_point)
                 if code_point == code_points or code_point in code_points:
                     total_remaining -= 1
-                    if code_point not in self._glyphs:
+                    if code_point not in self._glyphs or not self._glyphs[code_point]:
                         desired_character = True
                         current_info = {"bitmap": None, "bounds": None, "shift": None}
             elif line.startswith(b"DWIDTH"):

adafruit_bitmap_font/glyph_cache.py

@@ -10,6 +10,7 @@ def get_glyph(self, code_point):
 
         s = set()
         s.add(code_point)
+        self._glyphs[code_point] = None
         self.load_glyphs(s)
         gc.collect()
         return self._glyphs[code_point]