revise parcoords unselected.line color & opacity dflts

Author: archmoj

src/traces/parcoords/attributes.js

@@ -139,17 +139,24 @@ module.exports = {
         line: {
             color: {
                 valType: 'color',
-                dflt: '',
+                dflt: '#777',
                 editType: 'plot',
-                description: 'Sets the color of unselected lines.'
+                description: [
+                    'Sets the base color of unselected lines.',
+                    'in connection with `unselected.line.opacity`.'
+                ].join(' ')
             },
             opacity: {
                 valType: 'number',
                 min: 0,
                 max: 1,
                 dflt: 'auto',
                 editType: 'plot',
-                description: 'Sets the opacity of unselected lines.'
+                description: [
+                    'Sets the opacity of unselected lines.',
+                    'The default *auto* decreases the opacity smoothly as the number of lines increases.',
+                    'Use *1* to achieve exact `unselected.line.color`.'
+                ].join(' ')
             },
             editType: 'plot'
         },

src/traces/parcoords/defaults.js

@@ -71,10 +71,6 @@ module.exports = function supplyDefaults(traceIn, traceOut, defaultColor, layout
         return Lib.coerce(traceIn, traceOut, attributes, attr, dflt);
     }
 
-    function coerce2(attr, dflt) {
-        return Lib.coerce2(traceIn, traceOut, attributes, attr, dflt);
-    }
-
     var dimensionsIn = traceIn.dimensions;
     if(Array.isArray(dimensionsIn) && dimensionsIn.length > maxDimensionCount) {
         Lib.log('parcoords traces support up to ' + maxDimensionCount + ' dimensions at the moment');
@@ -112,6 +108,6 @@ module.exports = function supplyDefaults(traceIn, traceOut, defaultColor, layout
     coerce('labelangle');
     coerce('labelside');
 
-    var unselectedLineColor = coerce2('unselected.line.color');
-    coerce('unselected.line.opacity', unselectedLineColor ? 1 : 'auto');
+    coerce('unselected.line.color');
+    coerce('unselected.line.opacity');
 };

src/traces/parcoords/parcoords.js

@@ -150,7 +150,7 @@ function model(layout, d, i) {
     var lineColor = helpers.convertTypedArray(cd0.lineColor);
     var line = trace.line;
     var deselectedLines = {
-        color: rgba(trace.unselected.line.color || '#777'),
+        color: rgba(trace.unselected.line.color),
         opacity: trace.unselected.line.opacity
     };
     var cOpts = Colorscale.extractOpts(line);

test/image/baselines/gl2d_parcoords_constraints.png

@@ -1,5 +1,6 @@
 {
   "layout": {
+    "paper_bgcolor": "lightgray",
     "width": 1000,
     "height": 400
   },
@@ -26,6 +27,7 @@
 
     "unselected": {
       "line": {
+        "opacity": 1,
         "color": "white"
       }
     },

test/image/mocks/gl2d_parcoords_constraints.json

@@ -40359,14 +40359,14 @@
      "editType": "plot",
      "line": {
       "color": {
-       "description": "Sets the color of unselected lines.",
-       "dflt": "",
+       "description": "Sets the base color of unselected lines. in connection with `unselected.line.opacity`.",
+       "dflt": "#777",
        "editType": "plot",
        "valType": "color"
       },
       "editType": "plot",
       "opacity": {
-       "description": "Sets the opacity of unselected lines.",
+       "description": "Sets the opacity of unselected lines. The default *auto* decreases the opacity smoothly as the number of lines increases. Use *1* to achieve exact `unselected.line.color`.",
        "dflt": "auto",
        "editType": "plot",
        "max": 1,