visibleTargetCount for cleaner arc calculation

src/arc.js

@@ -10,9 +10,8 @@ c3_chart_internal_fn.initPie = function () {
 
 c3_chart_internal_fn.updateRadius = function () {
     var $$ = this, config = $$.config,
-        visibleTargetCount = $$.data.targets.length - $$.hiddenTargetIds.length,
         w = config.gauge_width || config.donut_width,
-        gaugeArcWidth = visibleTargetCount * 5; // 5 = minimal arc width of one arc in multi arc gauge; TODO in config
+        gaugeArcWidth = $$.visibleTargetCount * 5; // 5 = minimal arc width of one arc in multi arc gauge; TODO in config
     $$.radiusExpanded = Math.min($$.arcWidth, $$.arcHeight) / 2 * ($$.hasType('gauge') ? 0.85 : 1);
     $$.radius = $$.radiusExpanded * 0.95;
     $$.innerRadiusRatio = w ? ($$.radius - w) / $$.radius : 0.6;
@@ -56,7 +55,7 @@ c3_chart_internal_fn.updateAngle = function (d) {
 
 c3_chart_internal_fn.getSvgArc = function () {
     var $$ = this, hasGaugeType = $$.hasType('gauge'),
-        singleArcWidth = $$.gaugeArcWidth / ($$.data.targets.length - $$.hiddenTargetIds.length), // TODO auslagern
+        singleArcWidth = $$.gaugeArcWidth / $$.visibleTargetCount,
         arc = $$.d3.svg.arc().outerRadius(function(d) {
             return hasGaugeType ? $$.radius - singleArcWidth * d.index : $$.radius;
         }).innerRadius(function(d) {
@@ -76,7 +75,7 @@ c3_chart_internal_fn.getSvgArc = function () {
 c3_chart_internal_fn.getSvgArcExpanded = function (rate) {
     rate = rate || 1;
     var $$ = this, hasGaugeType = $$.hasType('gauge'),
-        singleArcWidth = $$.gaugeArcWidth / ($$.data.targets.length - $$.hiddenTargetIds.length), // TODO auslagern
+        singleArcWidth = $$.gaugeArcWidth / $$.visibleTargetCount,
         expandWidth = Math.min($$.radiusExpanded * rate - $$.radius, singleArcWidth * 0.8 - (1 - rate) * 100),
         arc = $$.d3.svg.arc().outerRadius(function(d){
             return hasGaugeType ? $$.radius - singleArcWidth * d.index + expandWidth : $$.radiusExpanded * rate;

src/core.js

@@ -135,6 +135,7 @@ c3_chart_internal_fn.initParams = function () {
         ["%Y/%-m/%-d", function () { return true; }]
     ]);
 
+    $$.visibleTargetCount = config.data_hide === true ? 0 : (config.data_columns ? (config.data_columns.length - (config.data_hide ? config.data_hide.length : 0)) : 0);
     $$.hiddenTargetIds = [];
     $$.hiddenLegendIds = [];
     $$.focusedTargetIds = [];

src/data.js

@@ -176,9 +176,11 @@ c3_chart_internal_fn.mapTargetsToUniqueXs = function (targets) {
 };
 c3_chart_internal_fn.addHiddenTargetIds = function (targetIds) {
     this.hiddenTargetIds = this.hiddenTargetIds.concat(targetIds);
+    this.visibleTargetCount -= targetIds.length;
 };
 c3_chart_internal_fn.removeHiddenTargetIds = function (targetIds) {
     this.hiddenTargetIds = this.hiddenTargetIds.filter(function (id) { return targetIds.indexOf(id) < 0; });
+    this.visibleTargetCount += targetIds.length;
 };
 c3_chart_internal_fn.addHiddenLegendIds = function (targetIds) {
     this.hiddenLegendIds = this.hiddenLegendIds.concat(targetIds);