lib: generalize filterVisible utils

- so that all array containers (not just gd.data) can use it.

src/lib/filter_visible.js

@@ -9,14 +9,21 @@
 
 'use strict';
 
-module.exports = function filterVisible(dataIn) {
-    var dataOut = [];
+/** Filter out object items with visible !== true
+ *  insider array container.
+ *
+ *  @param {array of objects} container
+ *  @return {array of objects} of length <= container
+ *
+ */
+module.exports = function filterVisible(container) {
+    var out = [];
 
-    for(var i = 0; i < dataIn.length; i++) {
-        var trace = dataIn[i];
+    for(var i = 0; i < container.length; i++) {
+        var item = container[i];
 
-        if(trace.visible === true) dataOut.push(trace);
+        if(item.visible === true) out.push(item);
     }
 
-    return dataOut;
+    return out;
 };

src/lib/index.js

@@ -76,6 +76,8 @@ lib.error = loggersModule.error;
 lib.notifier = require('./notifier');
 
 lib.filterUnique = require('./filter_unique');
+lib.filterVisible = require('./filter_visible');
+
 
 /**
  * swap x and y of the same attribute in container cont

src/plots/ternary/ternary.js

@@ -19,7 +19,6 @@ var Drawing = require('../../components/drawing');
 var setConvert = require('../cartesian/set_convert');
 var extendFlat = require('../../lib/extend').extendFlat;
 var Axes = require('../cartesian/axes');
-var filterVisible = require('../../lib/filter_visible');
 var dragElement = require('../../components/dragelement');
 var Titles = require('../../components/titles');
 var prepSelect = require('../cartesian/select');
@@ -94,7 +93,7 @@ proto.plot = function(ternaryData, fullLayout) {
         var moduleData = traceHash[moduleNames[i]];
         var _module = moduleData[0]._module;
 
-        _module.plot(_this, filterVisible(moduleData), ternaryLayout);
+        _module.plot(_this, Lib.filterVisible(moduleData), ternaryLayout);
     }
 
     _this.traceHash = traceHash;