Update the pixel_shader usage of OnDiskBitmap

Author: lesamouraipourpre

examples/gizmo_eink_simpletest.py

@@ -16,7 +16,12 @@
 with open("/display-ruler.bmp", "rb") as file:
     picture = displayio.OnDiskBitmap(file)
     # Create a Tilegrid with the bitmap and put in the displayio group
-    sprite = displayio.TileGrid(picture, pixel_shader=displayio.ColorConverter())
+    sprite = displayio.TileGrid(
+        picture,
+        pixel_shader=getattr(picture, "pixel_shader", displayio.ColorConverter()),
+        # TODO: Once CP6 is no longer supported, replace the above line with below
+        # pixel_shader=picture.pixel_shader,
+    )
     display_group.append(sprite)
 
     # Place the display group on the screen

examples/gizmo_tft_thermometer.py

@@ -44,7 +44,12 @@ def c_to_f(c_val):
     bitmap = displayio.OnDiskBitmap(bitmap_file)
 
     # Create a TileGrid to hold the bitmap
-    tile_grid = displayio.TileGrid(bitmap, pixel_shader=displayio.ColorConverter())
+    tile_grid = displayio.TileGrid(
+        bitmap,
+        pixel_shader=getattr(bitmap, "pixel_shader", displayio.ColorConverter()),
+        # TODO: Once CP6 is no longer supported, replace the above line with below
+        # pixel_shader=bitmap.pixel_shader,
+    )
 
     # Create a Group to hold the TileGrid
     group = displayio.Group()