Add Shift modes to neopixel node

hardware/neopixel/README.md

@@ -2,14 +2,15 @@ node-red-node-pi-neopixel
 =========================
 
 A <a href="http://nodered.org" target="_new">Node-RED</a> node to drive a strip
-of Neopixel or WS2812 LEDs.
+of Neopixel or WS2812 LEDs from a Raspberry Pi.
 
 Pre-requisites
 --------------
 
-The Unicorn HAT python drivers need to be pre-installed... This is the easiest way to get the neopixel driver installed... see the
-<a "href=http://learn.pimoroni.com/tutorial/unicorn-hat/getting-started-with-unicorn-hat">
-Pimorini Getting Started with Unicorn HAT</a> page.
+The Neopixel python driver need to be pre-installed... The easiest way to get
+the driver installed is to use the Unicorn HAT drivers install script... see the
+<a href="http://learn.pimoroni.com/tutorial/unicorn-hat/getting-started-with-unicorn-hat" target="_new">
+Pimoroni Getting Started with Unicorn HAT</a> page.
 
     curl -sS get.pimoroni.com/unicornhat | bash
 
@@ -21,22 +22,29 @@ Usually this is `~/.node-red`
 
     npm install node-red-node-pi-neopixel
 
+The data pin of the pixels should be connected to physical pin 12 - GPIO 18 of the Pi.
+*Note:* this may conflict with audio playback.
+
 Usage
 -----
 
 Defaults to a bar chart style mode using configured foreground and background colours.
 
-It can accept a number in **msg.payload** that can be either the number of pixels, or a percentage of the total length.
+It can accept a number in **msg.payload** that can be either the number of pixels,
+or a percentage of the total length.
 
-If you want to change the foregound colour, you can set **msg.payload** to a comma separated string of `html_colour,length`.
+If you want to change the foreground colour, you can set **msg.payload** to a
+comma separated string of `html_colour,length` or `length,html_colour`
 
-To set the background just set **msg.payload** `html_colour` name.
+To set the background just set **msg.payload** to an `html_colour` name.
 <a href="http://html-color-codes.info/color-names/" target="_top">Here
 is a list</a> of html_colour names.
 
-The `nth` pixel is set by **msg.payload** with a CSV string `n,r,g,b`
+You can also select shift modes where a single colour pixel is added to either
+the start or the end of the strip, shifting all the others along by one.
+
+The `nth` pixel can be set by **msg.payload** with a CSV string `n,r,g,b` ,
+where r, g and b are 0-255.
 
 A range of pixels from `x` to `y` can be set by **msg.payload**
 with a CSV string `x,y,r,g,b`
-
-The pixels data line should be connected to Pi physical pin 12 - GPIO 18. *Note:* this may conflict with audio playback.

hardware/neopixel/neopix.py

@@ -32,6 +32,13 @@ if sys.version_info >= (3,0):
 
 LED_COUNT = int(sys.argv[1])
 WAIT_MS = int(sys.argv[2])
+MODE = sys.argv[3]
+
+def getRGBfromI(RGBint):
+    blue =  RGBint & 255
+    green = (RGBint >> 8) & 255
+    red =   (RGBint >> 16) & 255
+    return red, green, blue
 
 # Define functions which animate LEDs in various ways.
 def setPixel(strip, i, color):
@@ -53,6 +60,24 @@ def colorWipe(strip, color, wait_ms=30):
         strip.show()
         time.sleep(wait_ms/1000.0)
 
+def shiftUp(strip, color, wait_ms=30):
+    """Shift all pixels one way."""
+    for i in range(strip.numPixels()):
+        strip.setPixelColor(LED_COUNT-i, strip.getPixelColor(LED_COUNT-i-1))
+        strip.show()
+        time.sleep(wait_ms/1000.0)
+    strip.setPixelColor(0,color)
+    strip.show()
+
+def shiftDown(strip, color, wait_ms=30):
+    """Shift all pixels the other way."""
+    for i in range(strip.numPixels()):
+        strip.setPixelColor(i, strip.getPixelColor(i+1))
+        strip.show()
+        time.sleep(wait_ms/1000.0)
+    strip.setPixelColor(LED_COUNT-1,color)
+    strip.show()
+
 def wheel(pos):
     """Generate rainbow colors across 0-255 positions."""
     if pos < 85:
@@ -103,12 +128,18 @@ if __name__ == '__main__':
             data = raw_input()
             bits = data.split(',')
             if len(bits) == 3:
+                if MODE == "shiftu":
+                    shiftUp(strip, Color(int(bits[0]), int(bits[1]), int(bits[2])), WAIT_MS)
+                elif MODE == "shiftd":
+                    shiftDown(strip, Color(int(bits[0]), int(bits[1]), int(bits[2])), WAIT_MS)
+                else:
                     colorWipe(strip, Color(int(bits[0]), int(bits[1]), int(bits[2])), WAIT_MS)
-            if len(bits) == 4:
+            if (MODE[0] == 'p' and len(bits) == 4):
                 setPixel(strip, int(bits[0]), Color(int(bits[1]), int(bits[2]), int(bits[3]) ))
-            if len(bits) == 5:
+            if (MODE[0] == 'p' and len(bits) == 5):
                 setPixels(strip, int(bits[0]), int(bits[1]), Color(int(bits[2]), int(bits[3]), int(bits[4]) ), WAIT_MS)
         except (EOFError, SystemExit):  # hopefully always caused by us sigint'ing the program
             sys.exit(0)
         except Exception as ex:
             print "bad data: "+data
+            print ex

hardware/neopixel/neopixel.html

@@ -32,6 +32,8 @@
     <select id="node-input-mode" style="width:73%">
         <option value="pcent">Percent of length</option>
         <option value="pixels">Number of pixels</option>
+        <option value="shiftu">Add pixel to start</option>
+        <option value="shiftd">Add pixel to end</option>
     </select>
 </div>
 <div class="form-row">
@@ -53,6 +55,7 @@
     <p>To set the background just send an <i>html colour</i> name.
     <a href="http://html-color-codes.info/color-names/" target="_top">Here
     is a list</a> of html colour names.<p>
+    <p>You can also select shift modes where a single colour pixel is added to either the start or the end of the strip.</p>
     <p>The <i>nth</i> pixel is set by <b>msg.payload</b> with a CSV string <i>n,r,g,b</i>
     <!-- <p>The whole strip is set by <b>msg.payload</b> with a CSV string <i>r,g,b</i> -->
     <p>A range of pixels from <i>x</i> to <i>y</i> can be set by <b>msg.payload</b>

hardware/neopixel/neopixel.js

@@ -94,7 +94,7 @@ module.exports = function(RED) {
             }
         }
 
-        node.child = spawn(piCommand, [node.pixels, node.wipe]);
+        node.child = spawn(piCommand, [node.pixels, node.wipe, node.mode]);
         node.status({fill:"green",shape:"dot",text:"ok"});
 
         node.on("input", inputlistener);

hardware/neopixel/package.json

@@ -1,6 +1,6 @@
 {
     "name"          : "node-red-node-pi-neopixel",
-    "version"       : "0.0.1",
+    "version"       : "0.0.2",
     "description"   : "A Node-RED node to output to a neopixel (ws2812) string of LEDS from a Raspberry Pi.",
     "dependencies"  : {
     },