Fix to zoom out based on zoom.x.min/max - #603

c3.js

@@ -1581,9 +1581,8 @@
         return $$.x.domain();
     };
     c3_chart_internal_fn.trimXDomain = function (domain) {
-        var $$ = this, config = $$.config, d3 = $$.d3;
-        var min = d3.min([$$.orgXDomain[0], config.zoom_x_min]);
-        var max = d3.max([$$.orgXDomain[1], config.zoom_x_max]);
+        var zoomDomain = this.getZoomDomain(),
+            min = zoomDomain[0], max = zoomDomain[1];
         if (domain[0] <= min) {
             domain[1] = +domain[1] + (min - domain[0]);
             domain[0] = min;
@@ -5522,12 +5521,18 @@
             return [extent[0], Math.max($$.getMaxDataCount() / extent[1], extent[1])];
         };
         $$.zoom.updateScaleExtent = function () {
-            var ratio = diffDomain($$.x.orgDomain()) / diffDomain($$.orgXDomain),
+            var ratio = diffDomain($$.x.orgDomain()) / diffDomain($$.getZoomDomain()),
                 extent = this.orgScaleExtent();
             this.scaleExtent([extent[0] * ratio, extent[1] * ratio]);
             return this;
         };
     };
+    c3_chart_internal_fn.getZoomDomain = function () {
+        var $$ = this, config = $$.config, d3 = $$.d3,
+            min = d3.min([$$.orgXDomain[0], config.zoom_x_min]),
+            max = d3.max([$$.orgXDomain[1], config.zoom_x_max]);
+        return [min, max];
+    };
     c3_chart_internal_fn.updateZoom = function () {
         var $$ = this, z = $$.config.zoom_enabled ? $$.zoom : function () {};
         $$.main.select('.' + CLASS.zoomRect).call(z).on("dblclick.zoom", null);

src/domain.js

@@ -221,9 +221,8 @@ c3_chart_internal_fn.updateXDomain = function (targets, withUpdateXDomain, withU
     return $$.x.domain();
 };
 c3_chart_internal_fn.trimXDomain = function (domain) {
-    var $$ = this, config = $$.config, d3 = $$.d3;
-    var min = d3.min([$$.orgXDomain[0], config.zoom_x_min]);
-    var max = d3.max([$$.orgXDomain[1], config.zoom_x_max]);
+    var zoomDomain = this.getZoomDomain(),
+        min = zoomDomain[0], max = zoomDomain[1];
     if (domain[0] <= min) {
         domain[1] = +domain[1] + (min - domain[0]);
         domain[0] = min;

src/zoom.js

@@ -28,12 +28,18 @@ c3_chart_internal_fn.initZoom = function () {
         return [extent[0], Math.max($$.getMaxDataCount() / extent[1], extent[1])];
     };
     $$.zoom.updateScaleExtent = function () {
-        var ratio = diffDomain($$.x.orgDomain()) / diffDomain($$.orgXDomain),
+        var ratio = diffDomain($$.x.orgDomain()) / diffDomain($$.getZoomDomain()),
             extent = this.orgScaleExtent();
         this.scaleExtent([extent[0] * ratio, extent[1] * ratio]);
         return this;
     };
 };
+c3_chart_internal_fn.getZoomDomain = function () {
+    var $$ = this, config = $$.config, d3 = $$.d3,
+        min = d3.min([$$.orgXDomain[0], config.zoom_x_min]),
+        max = d3.max([$$.orgXDomain[1], config.zoom_x_max]);
+    return [min, max];
+};
 c3_chart_internal_fn.updateZoom = function () {
     var $$ = this, z = $$.config.zoom_enabled ? $$.zoom : function () {};
     $$.main.select('.' + CLASS.zoomRect).call(z).on("dblclick.zoom", null);