Bug fixes for SSD1306

[hackapet/Adafruit_Blinka_Displayio.git] / displayio / _display.py

diff --git a/displayio/_display.py b/displayio/_display.py
index 74ee0957b697e3a494dfec6fa29ed009916fac3a..3f6d7b68d10886be92063abdee51e4205095a2fd 100644 (file)
--- a/displayio/_display.py
+++ b/displayio/_display.py
@@ -18,7 +18,6 @@ displayio for Blinka
 """
 
 import time
-import struct
 from array import array
 from typing import Optional
 import digitalio
@@ -329,7 +328,6 @@ class Display:
     def _refresh_area(self, area) -> bool:
         """Loop through dirty areas and redraw that area."""
         # pylint: disable=too-many-locals
-        buffer_size = 128
 
         clipped = Area()
         # Clip the area to the display by overlapping the areas.
@@ -338,9 +336,12 @@ class Display:
             return True
 
         rows_per_buffer = clipped.height()
-        pixels_per_word = (struct.calcsize("I") * 8) // self._core.colorspace.depth
+        pixels_per_word = 32 // self._core.colorspace.depth
         pixels_per_buffer = clipped.size()
 
+        # We should have lots of memory
+        buffer_size = clipped.size() // pixels_per_word
+
         subrectangles = 1
         # for SH1107 and other boundary constrained controllers
         #      write one single row at a time
@@ -366,11 +367,7 @@ class Display:
             buffer_size = pixels_per_buffer // pixels_per_word
             if pixels_per_buffer % pixels_per_word:
                 buffer_size += 1
-
-        # TODO: Optimize with memoryview
-        buffer = bytearray([0] * (buffer_size * struct.calcsize("I")))
-        mask_length = (pixels_per_buffer // 32) + 1
-        mask = array("L", [0] * mask_length)
+        mask_length = (pixels_per_buffer // 8) + 1  # 1 bit per pixel + 1
         remaining_rows = clipped.height()
 
         for subrect_index in range(subrectangles):
@@ -393,6 +390,8 @@ class Display:
                     8 // self._core.colorspace.depth
                 )
 
+            buffer = memoryview(bytearray([0] * (buffer_size * 4)))
+            mask = memoryview(bytearray([0] * mask_length))
             self._core.fill_area(subrectangle, mask, buffer)
             self._core.begin_transaction()
             self._send_pixels(buffer[:subrectangle_size_bytes])
@@ -405,13 +404,13 @@ class Display:
             raise ValueError("Display must have a 16 bit colorspace.")
 
         area = Area(0, y, self._core.width, y + 1)
-        pixels_per_word = (struct.calcsize("I") * 8) // self._core.colorspace.depth
+        pixels_per_word = 32 // self._core.colorspace.depth
         buffer_size = self._core.width // pixels_per_word
         pixels_per_buffer = area.size()
         if pixels_per_buffer % pixels_per_word:
             buffer_size += 1
 
-        buffer = bytearray([0] * (buffer_size * struct.calcsize("I")))
+        buffer = bytearray([0] * (buffer_size * 4))
         mask_length = (pixels_per_buffer // 32) + 1
         mask = array("L", [0x00000000] * mask_length)
         self._core.fill_area(area, mask, buffer)
@@ -461,7 +460,7 @@ class Display:
                     self._core.send(
                         DISPLAY_COMMAND,
                         CHIP_SELECT_TOGGLE_EVERY_BYTE,
-                        bytes([self._brightness_command, 0xFF * value]),
+                        bytes([self._brightness_command, round(0xFF * value)]),
                     )
                 else:
                     self._core.send(