add example to control pixels independently

v2/backend/arduino/VideoDisplay/VideoDisplay.ino

@@ -92,7 +92,7 @@
 
 
 //const int ledsPerStrip = LED_WIDTH * LED_HEIGHT / 8;
-const int ledsPerStrip = 40;
+const int ledsPerStrip = 700;
 
 DMAMEM int displayMemory[ledsPerStrip*6];
 int drawingMemory[ledsPerStrip*6];

v2/backend/processing/PixelControl/PixelControl.pyde

@@ -0,0 +1,107 @@
+add_library('serial')
+import math
+import jarray
+
+gamma = 1.7
+brightness = 4
+errorCount = 0
+framerate = 30
+dimension = 0 
+
+ledSerial = None
+data = None
+
+current_px = 0
+
+def serialConfigure(portName):
+    global ledSerial
+    try:
+        ledSerial = Serial(this, portName)
+        if ledSerial is None:
+            raise NullPointerException()
+        ledSerial.write('?')
+    except Exception as e:
+        println("Serial port " + portName + " does not exist or is non-functional")
+        errorCount += 1
+        return
+    delay(50);
+    line_serial = ledSerial.readStringUntil(10)
+    if (line is None):
+        println("Serial port " + portName + " is not responding.")
+        println("Is it really a Teensy 3.0 running VideoDisplay?")
+        errorCount += 1
+        return
+    
+    param = line_serial.split(",")
+    if (len(param) != 12):
+        println("Error: port " + portName + " did not respond to LED config query")
+        errorCount += 1
+        return
+
+def image2data(data):
+    offset = 3
+    for x in xrange(0, dimension, 1):
+        pixel = [colorWiring(pixels[x]) for i in range(0, 8)]
+        imgmask = 0x800000
+        while imgmask != 0:
+            b = 0
+            for i in range(0, 8):
+                if ((pixel[i] & imgmask) != 0):
+                    b |= (1 << i)
+            if b > 127:
+                # Convert to signed bytes (expected by jarray)
+                b -= 2**8
+            data[offset] = b
+            offset += 1
+            imgmask >>= 1
+
+def colorWiring(c):
+    red = (c & 0xFF0000) >> 16
+    green = (c & 0x00FF00) >> 8
+    blue = (c & 0x0000FF)
+    red = gammatable[red] >> 8
+    green = gammatable[green] >> 8
+    blue = gammatable[blue] >> 8
+    return (green << 16) | (red << 8) | (blue)
+
+def send_serial():
+    image2data(data)
+    ledSerial.write(data)
+    
+def prepare_data():
+    global data
+    data = jarray.zeros(dimension * 24 + 3, "b")
+    data[0] = ord('*')
+    usec = int((1000000.0 / framerate) * 0.75)
+    data[1] = (usec % 256) - 2**8
+    data[2] = usec >> 8
+
+def setup():
+    global gammatable
+    global dimension
+    size(700, 1)
+    dimension = width * height
+    frameRate(framerate)
+    serialConfigure("/dev/ttyACM0") 
+    if (errorCount > 0):
+        exit()
+    gammatable = [int((math.pow(i / 255.0, gamma) * 255.0 + 0.5) * brightness) for i in range(0, 256)]
+    prepare_data()
+    loadPixels()
+    for i in range(dimension):
+        pixels[i] = color(0, 0, 0)
+    updatePixels()
+
+def draw():
+    global current_px
+    pixels[current_px] = color(0, 255, 0)
+    if current_px == 0:
+        pixels[len(pixels) - 1] = color(0, 0, 0)
+    else:
+        pixels[current_px - 1] = color(0, 0, 0)
+    updatePixels()
+    if current_px == len(pixels) - 1:
+        current_px = 0
+    else: 
+        current_px += 1
+    send_serial()