test pattern

config.json

@@ -1,3 +1,6 @@
 {
-  
+  "leds": 450,
+  "brightness": 200,
+  "gpio": 18,
+  "type": "grb"
 }

index.js

@@ -7,7 +7,7 @@ global.cfg = cfg;
 
 server.recv(
   (res) => {
-    lights.parse_pattern(JSON.parse(res));
+    lights.set_pattern(JSON.parse(res));
   },
   (res) => {
     console.log(`error callback: ${res}`);

lights.js

@@ -1,7 +1,62 @@
-import * from 'rpi-ws281x-native'
+import * as ws281x from 'rpi-ws281x'
 
-const fade_ticks = 10;
+const fade_ticks = global.cfg.fade_ticks || 10;
+var pixels = new Uint32Array(global.cfg.leds);
+var pixel_cache = new Uint32Array(global.cfg.leds);
+var next_pattern = new Uint32Array(global.cfg.leds);
+var pattern = {}
 
-export function parse_pattern(pattern) {
-  console.log(pattern)
+ws281x.configure({
+  leds: global.cfg.leds || 300
+  brightness: global.cfg.brightness || 200,
+  gpio: global.cfg.gpio || 18,
+  stripType: global.cfg.type || 'grb'
+});
+
+export function set_pattern(pat) {
+  pattern = pat
+}
+
+function tick_pattern() {
+  // do the parsing stuff here
+  var r = Math.floor(Math.random() * 100)
+  var g = Math.floor(Math.random() * 100);
+  var b = Math.floor(Math.random() * 100);
+
+  for (int i = 0; i < global.cfg.leds; i++) {
+    if (i % 3 == 0) {
+      next_pattern[i] = r;
+      next_pattern[i + 1] = g;
+      next_pattern[i + 2] = b;
+    }
+  }
+}
+
+export function tick() {
+  var changed = false;
+  for (int i = 0; i < global.cfg.leds; i++) {
+    if (next_pattern[i] != pixels[i]) {
+      changed = true;
+      fade(i);
+    }
+  }
+  if (!changed) {
+    tick_pattern();
+  }
+  ws281x.render(pixels);
+}
+
+function fade(index) {
+  var original = pixel_cache[index];
+  var final = next_pattern[index];
+  var diff = final - original;
+  var interval = diff / fade_ticks;
+
+  if (Math.abs(final - pixels[index]) < interval) {
+    pixels[index] = final;
+    pixel_cache[index] = final;
+  }
+  else {
+    pixels[index] += interval;
+  }
 }