Add Gamma flag and Brightness control to node-red-node-pi-neopixel (#431)

Author: cymplecy

hardware/neopixel/neopix.py

@@ -36,9 +36,12 @@
 222,224,227,229,231,233,235,237,239,241,244,246,248,250,252,255]
 
 
-LED_COUNT = int(sys.argv[1])
-WAIT_MS = int(sys.argv[2])
+LED_COUNT = max(0,int(sys.argv[1]))
+WAIT_MS = max(0,int(sys.argv[2]))
 MODE = sys.argv[3]
+LED_BRIGHTNESS = min(255,int(max(0,float(sys.argv[4])) * 255 / 100))
+if (sys.argv[5].lower() != "true"):
+    LED_GAMMA = range(256)
 
 def getRGBfromI(RGBint):
     blue =  RGBint & 255
@@ -59,6 +62,12 @@ def setPixels(strip, s, e, color, wait_ms=30):
         strip.show()
         time.sleep(wait_ms/1000.0)
 
+def setBrightness(strip, brightness, wait_ms=30):
+    """Set overall brighness"""
+    strip.setBrightness(brightness)
+    strip.show()
+    time.sleep(wait_ms/1000.0)
+
 def colorWipe(strip, color, wait_ms=30):
     """Wipe color across display a pixel at a time."""
     for i in range(strip.numPixels()):
@@ -145,6 +154,9 @@ def rainbowCycle(strip, wait_ms=20, iterations=2):
         try:
             data = raw_input()
             bits = data.split(',')
+            if len(bits) == 2:
+                if bits[0] == "brightness":
+                    setBrightness(strip, min(255,max(0,int(bits[1]))), WAIT_MS)
             if len(bits) == 3:
                 if MODE == "shiftu":
                     shiftUp(strip, Color(int(bits[0]), int(bits[1]), int(bits[2])), WAIT_MS)

hardware/neopixel/neopixel.html

@@ -31,6 +31,16 @@
         <option value="grb">GRB</option>
     </select>
 </div>
+<div class="form-row">
+    <label for="node-input-brightness"><i class="fa fa-sun-o"></i> Brightness</label>
+    <input type="text" id="node-input-brightness" placeholder="number" style="width:60px;"> &nbsp;(0-100)
+</div>
+<div class="form-row">
+    <label for="node-input-gamma"> </label>
+    <label for="node-input-gamma" style="width:70%">
+    <input type="checkbox" id="node-input-gamma" style="display:inline-block; width:22px; vertical-align:baseline;"> Apply gamma correction
+    </label>
+</div>
 <br/>
 <div class="form-row">
     <label for="node-input-name"><i class="fa fa-tag"></i> Name</label>
@@ -53,6 +63,8 @@
     <!-- <p>The whole strip is set by <code>msg.payload</code> 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 <code>msg.payload</code>
     with a CSV string <i>x,y,r,g,b</i>
+    <p>By default, gamma correction is enabled but it can disabled which can be useful for working with low brightness levels</p>
+    <p><code>msg.brightness</code> can be used to dynamically set brightness level</p>
     <p>The pixels data line should be connected to Pi physical pin 12 - GPIO 18. <i>Note:</i>
     this may conflict with audio playback.</p>
     <p align="right"><a href="http://flows.nodered.org/node/node-red-node-pi-neopixel#usage">More info&nbsp;&nbsp;</a></p>
@@ -69,7 +81,9 @@
             fgnd: { value:"" },
             wipe: { value:"40", required:true, validate:RED.validators.number() },
             mode: { value:"pcent" },
-            rgb: { value:"rgb" }
+            rgb: { value:"rgb" },
+            brightness: { value:"100", required:true, validate:RED.validators.number() },
+            gamma: { value: true }
         },
         inputs:1,
         outputs:0,
@@ -82,6 +96,14 @@
             return this.name?"node_label_italic":"";
         },
         oneditprepare: function() {
+            if (this.gamma === undefined) {
+                this.gamma = true;
+                $("#node-input-gamma").prop('checked', true);
+            }
+            if (this.brightness === undefined) {
+                this.brighness = "100";
+                $("#node-input-brightness").val("100");
+            }
             var setstate = function () {
                 if ($('#node-input-mode').val().indexOf("shift") !== -1) {
                     $("#bgcol").hide();

hardware/neopixel/neopixel.js

@@ -35,8 +35,13 @@ module.exports = function(RED) {
         this.fgnd = n.fgnd || "128,128,128";
         this.mode = n.mode || "pcent";
         this.rgb = n.rgb || "rgb";
+        this.gamma = n.gamma;
+        if (this.gamma === undefined) { this.gamma = true; }
+        this.brightness = Number(n.brightness || 100);
         this.wipe = Number(n.wipe || 40);
         if (this.wipe < 0) { this.wipe = 0; }
+        if (this.brightness < 0) { this.brightness = 0; }
+        if (this.brightness > 100) { this.brightness = 100; }
         var node = this;
         var needle = "255,255,255";
         //var p1 = /^\#[A-Fa-f0-9]{6}$/
@@ -45,6 +50,9 @@ module.exports = function(RED) {
         var p4 = /^[0-9]+,[0-9]+,[0-9]+,[0-9]+,[0-9]+$/
 
         function inputlistener(msg) {
+            if (msg.hasOwnProperty("brightness")) {
+                node.child.stdin.write("brightness,"+msg.brightness.toString()+"\n"); 
+            }
             if (msg.hasOwnProperty("payload")) {
                 var pay = msg.payload.toString().toUpperCase();
                 var parts = pay.split(",");
@@ -101,8 +109,8 @@ module.exports = function(RED) {
                 else { node.warn("Invalid payload : "+pay); }
             }
         }
-
-        node.child = spawn(piCommand, [node.pixels, node.wipe, node.mode]);
+        node.warn("GAMMA: "+node.gamma);
+        node.child = spawn(piCommand, [node.pixels, node.wipe, node.mode, node.brightness, node.gamma]);
         node.status({fill:"green",shape:"dot",text:"ok"});
 
         node.on("input", inputlistener);

hardware/neopixel/package.json

@@ -1,22 +1,25 @@
 {
-    "name"          : "node-red-node-pi-neopixel",
-    "version"       : "0.0.16",
-    "description"   : "A Node-RED node to output to a neopixel (ws2812) string of LEDS from a Raspberry Pi.",
-    "dependencies"  : {
-    },
-    "repository" : {
-        "type":"git",
-        "url":"https://github.com/node-red/node-red-nodes/tree/master/hardware/neopixel"
+    "name": "node-red-node-pi-neopixel",
+    "version": "0.0.17",
+    "description": "A Node-RED node to output to a neopixel (ws2812) string of LEDS from a Raspberry Pi.",
+    "dependencies": {},
+    "repository": {
+        "type": "git",
+        "url": "https://github.com/node-red/node-red-nodes/tree/master/hardware/neopixel"
     },
     "license": "Apache-2.0",
-    "keywords": [ "node-red", "ws2812", "neopixel" ],
-    "node-red"      : {
-        "nodes"     : {
+    "keywords": [
+        "node-red",
+        "ws2812",
+        "neopixel"
+    ],
+    "node-red": {
+        "nodes": {
             "rpi-neopixels": "neopixel.js"
         }
     },
-    "scripts" : {
-        "postinstall" : "scripts/checklib.js"
+    "scripts": {
+        "postinstall": "scripts/checklib.js"
     },
     "author": {
         "name": "Dave Conway-Jones",