Code cleanup, re-organizing and tidying (#226)

* initial cleanup

* build

* additions and build

src/modules/Ndvi/Module.js

@@ -0,0 +1,59 @@
+/*
+ * NDVI with red filter (blue channel is infrared)
+ */
+module.exports = function Ndvi(options,UI) {
+
+  options = options || {};
+  options.filter = options.filter || "red";
+
+  // Tell the UI that a step has been set up.
+  UI.onSetup(options.step);
+  var output;
+
+  // The function which is called on every draw.
+  function draw(input,callback,progressObj) {
+
+    progressObj.stop(true);
+    progressObj.overrideFlag = true;
+
+    // Tell the UI that a step is being drawn.
+    UI.onDraw(options.step);
+    var step = this;
+
+    function changePixel(r, g, b, a) {
+      if (options.filter == "red") var ndvi = (b - r) / (1.00 * b + r);
+      if (options.filter == "blue") var ndvi = (r - b) / (1.00 * b + r);
+      var x = 255 * (ndvi + 1) / 2;
+      return [x, x, x, a];
+    }
+
+    function output(image,datauri,mimetype){
+
+      // This output is accessible by Image Sequencer
+      step.output = {src:datauri,format:mimetype};
+
+      // This output is accessible by the UI.
+      options.step.output = datauri;
+
+      // Tell the UI that step has been drawn succesfully.
+      UI.onComplete(options.step);
+    }
+    
+    return require('../_nomodule/PixelManipulation.js')(input, {
+      output: output,
+      changePixel: changePixel,
+      format: input.format,
+      image: options.image,
+      inBrowser: options.inBrowser,
+      callback: callback
+    });
+
+  }
+
+  return {
+    options: options,
+    draw: draw,
+    output: output,
+    UI:UI
+  }
+}