Code tweaks, add BMPs

Author: PaintYourDragon

CLUE_Light_Painter/bmps-30px/arrow.bmp

@@ -25,7 +25,7 @@
 # These are permanent global settings, can only change by editing the code:
 
 FLIP_SCREEN = True   # If True, turn CLUE screen & buttons upside-down
-PATH = '/bmps'       # Folder containing BMP images (or '' for root path)
+PATH = '/bmps-30px'  # Folder containing BMP images (or '' for root path)
 GAMMA = 2.6          # Correction factor for perceptually linear brightness
 NUM_PIXELS = 30      # LED strip length, half-meter is usu. 30 or 72 pixels
 PIXEL_PIN = board.D0 # Output pin for NeoPixel data

CLUE_Light_Painter/bmps-30px/rainbow.bmp

@@ -128,8 +128,11 @@ def scandir(self, path):
             BMP formats (e.g. compressed or paletted) are skipped.
             List will be alphabetically sorted.
         """
-        full_list = listdir(path)
         valid_list = []
+        try:
+            full_list = listdir(path)
+        except OSError:
+            return
         for entry in full_list:
             try:
                 with open(path + '/' + entry, "rb") as self.file: