Merge pull request #48 from dunkmann00/pixelbuf

Add support for Pixelbuf

Author: kattni

README.rst

@@ -26,7 +26,7 @@ It should be a float. For example, (0xFF,0,0, 1.0) is the brightest red possible
 
 .. note:: The int hex API represents the brightness of the white pixel when
   present by setting the RGB channels to identical values. For example, full
-  white is 0xffffff but is actually (0xff, 0xff, 0xff) in the tuple syntax. 
+  white is 0xffffff but is actually (0xff, 0xff, 0xff) in the tuple syntax.
 
 Dependencies
 =============

adafruit_dotstar.py

@@ -3,6 +3,7 @@
 # Copyright (c) 2016 Damien P. George (original Neopixel object)
 # Copyright (c) 2017 Ladyada
 # Copyright (c) 2017 Scott Shawcroft for Adafruit Industries
+# Copyright (c) 2019 Roy Hooper
 #
 # Permission is hereby granted, free of charge, to any person obtaining a copy
 # of this software and associated documentation files (the "Software"), to deal
@@ -23,30 +24,46 @@
 # THE SOFTWARE.
 
 """
-`adafruit_dotstar` - DotStar strip driver
-====================================================
+`adafruit_dotstar` - DotStar strip driver (for CircuitPython 5.0+ with _pixelbuf)
+=================================================================================
 
-* Author(s): Damien P. George, Limor Fried & Scott Shawcroft
+* Author(s): Damien P. George, Limor Fried, Scott Shawcroft & Roy Hooper
 """
+
+# pylint: disable=ungrouped-imports
+import sys
 import busio
 import digitalio
 
+if sys.implementation.version[0] < 5:
+    import adafruit_pypixelbuf as _pixelbuf
+else:
+    try:
+        import _pixelbuf
+    except ImportError:
+        import adafruit_pypixelbuf as _pixelbuf
+
 __version__ = "0.0.0-auto.0"
 __repo__ = "https://github.com/adafruit/Adafruit_CircuitPython_DotStar.git"
 
 START_HEADER_SIZE = 4
-LED_START = 0b11100000  # Three "1" bits, followed by 5 brightness bits
 
 # Pixel color order constants
-RGB = (0, 1, 2)
-RBG = (0, 2, 1)
-GRB = (1, 0, 2)
-GBR = (1, 2, 0)
-BRG = (2, 0, 1)
-BGR = (2, 1, 0)
-
-
-class DotStar:
+RBG = "PRBG"
+"""Red Blue Green"""
+RGB = "PRGB"
+"""Red Green Blue"""
+GRB = "PGRB"
+"""Green Red Blue"""
+GBR = "PGBR"
+"""Green Blue Red"""
+BRG = "PBRG"
+"""Blue Red Green"""
+BGR = "PBGR"
+"""Blue Green Red"""
+
+
+class DotStar(_pixelbuf.PixelBuf):
     """
     A sequence of dotstars.
 
@@ -56,16 +73,14 @@ class DotStar:
     :param float brightness: Brightness of the pixels between 0.0 and 1.0
     :param bool auto_write: True if the dotstars should immediately change when
         set. If False, `show` must be called explicitly.
-    :param tuple pixel_order: Set the pixel order on the strip - different
-        strips implement this differently. If you send red, and it looks blue
-        or green on the strip, modify this! It should be one of the values
-        above.
+    :param str pixel_order: Set the pixel order on the strip - different
+         strips implement this differently. If you send red, and it looks blue
+         or green on the strip, modify this! It should be one of the values above.
     :param int baudrate: Desired clock rate if using hardware SPI (ignored if
         using 'soft' SPI). This is only a recommendation; the actual clock
         rate may be slightly different depending on what the system hardware
         can provide.
 
-
     Example for Gemma M0:
 
     .. code-block:: python
@@ -79,6 +94,22 @@ class DotStar:
         with adafruit_dotstar.DotStar(APA102_SCK, APA102_MOSI, 1) as pixels:
             pixels[0] = RED
             time.sleep(2)
+
+    .. py:method:: DotStar.show()
+
+        Shows the new colors on the dotstars themselves if they haven't already
+        been autowritten.
+
+        The colors may or may not be showing after this function returns because
+        it may be done asynchronously.
+
+    .. py:method:: DotStar.fill(color)
+
+        Colors all dotstars the given ***color***.
+
+    .. py:attribute:: brightness
+
+        Overall brightness of all dotstars (0 to 1.0)
     """
 
     def __init__(
@@ -105,36 +136,29 @@ def __init__(
             self.dpin.direction = digitalio.Direction.OUTPUT
             self.cpin.direction = digitalio.Direction.OUTPUT
             self.cpin.value = False
-        self._n = n
+
         # Supply one extra clock cycle for each two pixels in the strip.
-        self.end_header_size = n // 16
+        trailer_size = n // 16
         if n % 16 != 0:
-            self.end_header_size += 1
-        self._buf = bytearray(n * 4 + START_HEADER_SIZE + self.end_header_size)
-        self.end_header_index = len(self._buf) - self.end_header_size
-        self.pixel_order = pixel_order
-        # Four empty bytes to start.
-        for i in range(START_HEADER_SIZE):
-            self._buf[i] = 0x00
-        # Mark the beginnings of each pixel.
-        for i in range(START_HEADER_SIZE, self.end_header_index, 4):
-            self._buf[i] = 0xFF
-        # 0xff bytes at the end.
-        for i in range(self.end_header_index, len(self._buf)):
-            self._buf[i] = 0xFF
-        self._brightness = 1.0
-        # Set auto_write to False temporarily so brightness setter does _not_
-        # call show() while in __init__.
-        self.auto_write = False
-        self.brightness = brightness
-        self.auto_write = auto_write
+            trailer_size += 1
+
+        # Four empty bytes for the header.
+        header = bytearray(START_HEADER_SIZE)
+        # 0xff bytes for the trailer.
+        trailer = bytearray(b"\xff") * trailer_size
+
+        super().__init__(
+            n,
+            byteorder=pixel_order,
+            brightness=brightness,
+            auto_write=auto_write,
+            header=header,
+            trailer=trailer,
+        )
 
     def deinit(self):
         """Blank out the DotStars and release the resources."""
-        self.auto_write = False
-        for i in range(START_HEADER_SIZE, self.end_header_index):
-            if i % 4 != 0:
-                self._buf[i] = 0
+        self.fill(0)
         self.show()
         if self._spi:
             self._spi.deinit()
@@ -151,136 +175,24 @@ def __exit__(self, exception_type, exception_value, traceback):
     def __repr__(self):
         return "[" + ", ".join([str(x) for x in self]) + "]"
 
-    def _set_item(self, index, value):
+    @property
+    def n(self):
         """
-        value can be one of three things:
-                a (r,g,b) list/tuple
-                a (r,g,b, brightness) list/tuple
-                a single, longer int that contains RGB values, like 0xFFFFFF
-            brightness, if specified should be a float 0-1
-
-        Set a pixel value. You can set per-pixel brightness here, if it's not passed it
-        will use the max value for pixel brightness value, which is a good default.
-
-        Important notes about the per-pixel brightness - it's accomplished by
-        PWMing the entire output of the LED, and that PWM is at a much
-        slower clock than the rest of the LEDs. This can cause problems in
-        Persistence of Vision Applications
+        The number of dotstars in the chain (read-only)
         """
+        return len(self)
 
-        offset = index * 4 + START_HEADER_SIZE
-        rgb = value
-        if isinstance(value, int):
-            rgb = (value >> 16, (value >> 8) & 0xFF, value & 0xFF)
-
-        if len(rgb) == 4:
-            brightness = value[3]
-            # Ignore value[3] below.
-        else:
-            brightness = 1
-
-        # LED startframe is three "1" bits, followed by 5 brightness bits
-        # then 8 bits for each of R, G, and B. The order of those 3 are configurable and
-        # vary based on hardware
-        # same as math.ceil(brightness * 31) & 0b00011111
-        # Idea from https://www.codeproject.com/Tips/700780/Fast-floor-ceiling-functions
-        brightness_byte = 32 - int(32 - brightness * 31) & 0b00011111
-        self._buf[offset] = brightness_byte | LED_START
-        self._buf[offset + 1] = rgb[self.pixel_order[0]]
-        self._buf[offset + 2] = rgb[self.pixel_order[1]]
-        self._buf[offset + 3] = rgb[self.pixel_order[2]]
-
-    def __setitem__(self, index, val):
-        if isinstance(index, slice):
-            start, stop, step = index.indices(self._n)
-            length = stop - start
-            if step != 0:
-                # same as math.ceil(length / step)
-                # Idea from https://fizzbuzzer.com/implement-a-ceil-function/
-                length = (length + step - 1) // step
-            if len(val) != length:
-                raise ValueError("Slice and input sequence size do not match.")
-            for val_i, in_i in enumerate(range(start, stop, step)):
-                self._set_item(in_i, val[val_i])
+    def _transmit(self, buffer):
+        if self._spi:
+            self._spi.write(buffer)
         else:
-            self._set_item(index, val)
-
-        if self.auto_write:
-            self.show()
-
-    def __getitem__(self, index):
-        if isinstance(index, slice):
-            out = []
-            for in_i in range(*index.indices(self._n)):
-                out.append(
-                    tuple(
-                        self._buf[in_i * 4 + (3 - i) + START_HEADER_SIZE]
-                        for i in range(3)
-                    )
-                )
-            return out
-        if index < 0:
-            index += len(self)
-        if index >= self._n or index < 0:
-            raise IndexError
-        offset = index * 4
-        return tuple(self._buf[offset + (3 - i) + START_HEADER_SIZE] for i in range(3))
-
-    def __len__(self):
-        return self._n
+            self._ds_writebytes(buffer)
 
-    @property
-    def brightness(self):
-        """Overall brightness of the pixel"""
-        return self._brightness
-
-    @brightness.setter
-    def brightness(self, brightness):
-        self._brightness = min(max(brightness, 0.0), 1.0)
-        if self.auto_write:
-            self.show()
-
-    def fill(self, color):
-        """Colors all pixels the given ***color***."""
-        auto_write = self.auto_write
-        self.auto_write = False
-        for i in range(self._n):
-            self[i] = color
-        if auto_write:
-            self.show()
-        self.auto_write = auto_write
-
-    def _ds_writebytes(self, buf):
-        for b in buf:
+    def _ds_writebytes(self, buffer):
+        for b in buffer:
             for _ in range(8):
                 self.dpin.value = b & 0x80
                 self.cpin.value = True
                 self.cpin.value = False
                 b = b << 1
-
-    def show(self):
-        """Shows the new colors on the pixels themselves if they haven't already
-        been autowritten.
-
-        The colors may or may not be showing after this function returns because
-        it may be done asynchronously."""
-        # Create a second output buffer if we need to compute brightness
-        buf = self._buf
-        if self.brightness < 1.0:
-            buf = bytearray(self._buf)
-            # Four empty bytes to start.
-            for i in range(START_HEADER_SIZE):
-                buf[i] = 0x00
-            for i in range(START_HEADER_SIZE, self.end_header_index):
-                buf[i] = (
-                    self._buf[i] if i % 4 == 0 else int(self._buf[i] * self._brightness)
-                )
-            # Four 0xff bytes at the end.
-            for i in range(self.end_header_index, len(buf)):
-                buf[i] = 0xFF
-
-        if self._spi:
-            self._spi.write(buf)
-        else:
-            self._ds_writebytes(buf)
-            self.cpin.value = False
+        self.cpin.value = False

examples/dotstar_image_pov.py

@@ -9,6 +9,7 @@
 # than through function calls or setters/getters...this is poor form as it
 # could break easily with future library changes, but is the only way right
 # now to do the POV as quickly as possible.
+# May require installing separate libraries.
 
 import board
 from PIL import Image
@@ -25,7 +26,7 @@
     board.MOSI,
     NUMPIXELS,
     auto_write=False,
-    brightness=0.25,
+    brightness=1.0,
     pixel_order=ORDER,
 )
 
@@ -42,41 +43,29 @@
 
 # Calculate gamma correction table, makes mid-range colors look 'right':
 GAMMA = bytearray(256)
+brightness = 0.25
 for i in range(256):
-    # Notice we access DOTS.brightness directly here...the gamma table will
-    # handle any brightness-scaling, so we can set the object brightness back
-    # to max and it won't need to perform brightness scaling on every write.
-    GAMMA[i] = int(pow(float(i) / 255.0, 2.7) * DOTS.brightness * 255.0 + 0.5)
-DOTS.brightness = 1.0
+    GAMMA[i] = int(pow(float(i) / 255.0, 2.7) * brightness * 255.0 + 0.5)
 
-# Allocate list of bytearrays, one for each column of image.
-# Each pixel REQUIRES 4 bytes (0xFF, B, G, R).
+# Allocate list of lists, one for each column of image.
 print("Allocating...")
 COLUMN = [0 for x in range(WIDTH)]
 for x in range(WIDTH):
-    COLUMN[x] = bytearray(HEIGHT * 4)
+    COLUMN[x] = [[0, 0, 0, 0] for _ in range(HEIGHT)]
 
-# Convert entire RGB image into column-wise bytearray list.
-# The dotstar_image_paint.py example uses the library's 'setter' operation
-# for each pixel to do any R/G/B reordering.  Because we're preparing data
-# directly for the strip, there's a reference to 'ORDER' here to rearrange
-# the color bytes as needed.
+# Convert entire RGB image into columnxrow 2D list.
 print("Converting...")
 for x in range(WIDTH):  # For each column of image
     for y in range(HEIGHT):  # For each pixel in column
         value = PIXELS[x, y]  # Read RGB pixel in image
-        y4 = y * 4  # Position in raw buffer
-        COLUMN[x][y4] = 0xFF  # Pixel start marker
-        y4 += 1  # Pixel color data start
-        COLUMN[x][y4 + ORDER[0]] = GAMMA[value[0]]  # Gamma-corrected R
-        COLUMN[x][y4 + ORDER[1]] = GAMMA[value[1]]  # Gamma-corrected G
-        COLUMN[x][y4 + ORDER[2]] = GAMMA[value[2]]  # Gamma-corrected B
+        COLUMN[x][y][0] = GAMMA[value[0]]  # Gamma-corrected R
+        COLUMN[x][y][1] = GAMMA[value[1]]  # Gamma-corrected G
+        COLUMN[x][y][2] = GAMMA[value[2]]  # Gamma-corrected B
+        COLUMN[x][y][3] = 1.0  # Brightness
 
 print("Displaying...")
 while True:  # Loop forever
 
-    # pylint: disable=protected-access
-    # (Really shouldn't access _buf directly, but needed for fastest POV)
     for x in range(WIDTH):  # For each column of image...
-        DOTS._buf[4 : 4 + HEIGHT * 4] = COLUMN[x]  # Copy column to DotStar buffer
+        DOTS[0 : DOTS.n] = COLUMN[x]  # Copy column to DotStar buffer
         DOTS.show()  # Send data to strip