Merge pull request #4437 from plotly/contour-heatmap-coloring-colorsc…

…ale-reversescale-fix

Fix colorbar of reversescale colorbars of heatmap-coloring contours

src/traces/contour/colorbar.js

@@ -8,7 +8,7 @@
 
 'use strict';
 
-var extractOpts = require('../../components/colorscale').extractOpts;
+var Colorscale = require('../../components/colorscale');
 var makeColorMap = require('./make_color_map');
 var endPlus = require('./end_plus');
 
@@ -20,8 +20,10 @@ function calc(gd, trace, opts) {
     var colorMap = makeColorMap(trace, {isColorbar: true});
 
     if(coloring === 'heatmap') {
-        var cOpts = extractOpts(trace);
-        opts._fillgradient = trace.colorscale;
+        var cOpts = Colorscale.extractOpts(trace);
+        opts._fillgradient = cOpts.reversescale ?
+            Colorscale.flipScale(cOpts.colorscale) :
+            cOpts.colorscale;
         opts._zrange = [cOpts.min, cOpts.max];
     } else if(coloring === 'fill') {
         opts._fillcolor = colorMap;

test/image/mocks/contour_heatmap_coloring_reversescale.json

@@ -0,0 +1,59 @@
+{
+  "data": [
+    {
+      "z": [
+        [ 10, 10.625, 12.5, 15.625, 20 ],
+        [ 5.625, 6.25, 8.125, 11.25, 15.625 ],
+        [ 2.5, 3.125, 5, 8.125, 12.5 ],
+        [ 0.625, 1.25, 3.125, 6.25, 10.625 ],
+        [ 0, 0.625, 2.5, 5.625, 10 ]
+      ],
+      "x": [ -9, -6, -5, -3, -1 ],
+      "y": [ 0, 1, 4, 5, 7 ],
+      "type": "contour",
+      "contours": {
+        "coloring": "heatmap"
+      },
+      "reversescale": true,
+      "colorbar": {
+        "len": 0.5,
+        "y": 1,
+        "yanchor": "top",
+        "title": {"text": "trace colorscale", "side": "right"}
+      }
+    },
+    {
+      "z": [
+        [ 10, 10.625, 12.5, 15.625, 20 ],
+        [ 5.625, 6.25, 8.125, 11.25, 15.625 ],
+        [ 2.5, 3.125, 5, 8.125, 12.5 ],
+        [ 0.625, 1.25, 3.125, 6.25, 10.625 ],
+        [ 0, 0.625, 2.5, 5.625, 10 ]
+      ],
+      "x": [ -9, -6, -5, -3, -1 ],
+      "y": [ 0, 1, 4, 5, 7 ],
+      "type": "contour",
+      "contours": {
+        "coloring": "heatmap"
+      },
+      "coloraxis": "coloraxis",
+      "xaxis": "x2",
+      "yaxis": "y2"
+    }
+  ],
+  "layout": {
+    "grid": {"rows": 2, "columns": 1, "pattern": "independent"},
+    "title": {
+      "text": "Setting the X and Y Coordinates in a Contour Plot + reverse scale"
+    },
+    "coloraxis": {
+      "reversescale": true,
+      "colorbar": {
+        "len": 0.5,
+        "y": 0,
+        "yanchor": "bottom",
+        "title": {"text": "coloraxis colorscale", "side": "right"}
+      }
+    }
+  }
+}