colorscale: split make_color_scale_function

- into extractScale and makeColorScaleFn

Author: etpinard

src/components/colorscale/extract_scale.js

@@ -0,0 +1,35 @@
+/**
+* Copyright 2012-2016, Plotly, Inc.
+* All rights reserved.
+*
+* This source code is licensed under the MIT license found in the
+* LICENSE file in the root directory of this source tree.
+*/
+
+
+'use strict';
+
+/**
+ * Extract colorscale into numeric domain and color range.
+ *
+ * @param {array} scl colorscale array of arrays
+ * @param {number} cmin minimum color value (used to clamp scale)
+ * @param {number} cmax maximum color value (used to clamp scale)
+ */
+module.exports = function extractScale(scl, cmin, cmax) {
+    var N = scl.length,
+        domain = new Array(N),
+        range = new Array(N);
+
+    for(var i = 0; i < N; i++) {
+        var si = scl[i];
+
+        domain[i] = cmin + si[0] * (cmax - cmin);
+        range[i] = si[1];
+    }
+
+    return {
+        domain: domain,
+        range: range
+    };
+};

src/components/colorscale/index.js

@@ -27,4 +27,6 @@ exports.getScale = require('./get_scale');
 
 exports.flipScale = require('./flip_scale');
 
-exports.makeScaleFunction = require('./make_scale_function');
+exports.extractScale = require('./extract_scale');
+
+exports.makeColorScaleFunc = require('./make_color_scale_func');

src/components/colorscale/make_scale_function.js renamed to src/components/colorscale/make_color_scale_func.js

@@ -18,64 +18,32 @@ var Color = require('../color');
 /**
  * General colorscale function generator.
  *
- * Can be called in two forms:
- *
- *  (1) makeScaleFunction(scl, { cmin: 0, cmax: 20 })
- *    where cmin and cmax are used to compute the scale domain and range.
- *
- *  (2) makeScaleFunction(scl, { domain: [0, 1, 3], range: [ 'red', 'green', 'blue'] })
- *    where domain and range are the precomputed values.
- *
- * @param {array} scl
- *  plotly.js colorscale array of arrays as found in fullData
+ * @param {object} specs output of Colorscale.extractScale or precomputed domain, range.
+ *  - domain {array}
+ *  - range {array}
  *
  * @param {object} opts
- *  - cmin {number} minimum color value (used to clamp scale)
- *  - cmax {number} maximum color value (used to clamp scale)
- *  - domain {array} precomputed domain
- *  - range {array} precomputed range
  *  - noNumericCheck {boolean} if true, scale func bypasses numeric checks
  *  - returnArray {boolean} if true, scale func return 4-item array instead of color strings
  *
  * @return {function}
  */
-module.exports = function makeScaleFunction(scl, opts) {
+module.exports = function makeColorScaleFunc(specs, opts) {
     opts = opts || {};
 
-    var N = scl.length;
-
-    var domain, rangeOrig, i;
-
-    if(opts.domain && opts.range) {
-        domain = opts.domain;
-        rangeOrig = opts.range;
-    }
-    else {
-        var cmin = opts.cmin,
-            cmax = opts.cmax;
-
-        domain = new Array(N);
-        rangeOrig = new Array(N);
-
-        for(i = 0; i < N; i++) {
-            var si = scl[i];
-
-            domain[i] = cmin + si[0] * (cmax - cmin);
-            rangeOrig[i] = si[1];
-        }
-    }
-
-    var range = new Array(N);
-
-    for(i = 0; i < N; i++) {
-        var rgba = tinycolor(rangeOrig[i]).toRgb();
+    var domain = specs.domain,
+        range = specs.range,
+        N = range.length,
+        _range = new Array(N);
 
-        range[i] = [rgba.r, rgba.g, rgba.b, rgba.a];
+    for(var i = 0; i < N; i++) {
+        var rgba = tinycolor(range[i]).toRgb();
+        _range[i] = [rgba.r, rgba.g, rgba.b, rgba.a];
     }
 
     var _sclFunc = d3.scale.linear()
         .domain(domain)
-        .range(range)
+        .range(_range)
         .clamp(true);
 
     var noNumericCheck = opts.noNumericCheck,
@@ -109,7 +77,7 @@ module.exports = function makeScaleFunction(scl, opts) {
 
     sclFunc.domain = _sclFunc.domain;
 
-    sclFunc.range = function() { return rangeOrig; };
+    sclFunc.range = function() { return range; };
 
     return sclFunc;
 };

src/components/drawing/index.js

@@ -14,13 +14,13 @@ var isNumeric = require('fast-isnumeric');
 
 var Registry = require('../../registry');
 var Color = require('../color');
+var Colorscale = require('../colorscale');
 var Lib = require('../../lib');
 var svgTextUtils = require('../../lib/svg_text_utils');
 
 var xmlnsNamespaces = require('../../constants/xmlns_namespaces');
 var subTypes = require('../../traces/scatter/subtypes');
 var makeBubbleSizeFn = require('../../traces/scatter/make_bubble_size_func');
-var makeScaleFunction = require('../colorscale/make_scale_function');
 
 var drawing = module.exports = {};
 
@@ -332,10 +332,9 @@ drawing.tryColorscale = function(cont, contIn, prefix) {
             Lib.nestedProperty(contIn, prefix + 'cmax').set(max);
         }
 
-        return makeScaleFunction(scl, {
-            cmin: min,
-            cmax: max
-        });
+        return Colorscale.makeColorScaleFunc(
+            Colorscale.extractScale(scl, min, max)
+        );
     }
     else return Lib.identity;
 };

src/lib/gl_format_color.js

@@ -12,7 +12,7 @@
 var tinycolor = require('tinycolor2');
 var isNumeric = require('fast-isnumeric');
 
-var makeScaleFunction = require('../components/colorscale/make_scale_function');
+var Colorscale = require('../components/colorscale');
 var colorDflt = require('../components/color/attributes').defaultLine;
 
 var str2RgbaArray = require('./str2rgbarray');
@@ -42,10 +42,13 @@ function formatColor(containerIn, opacityIn, len) {
     var sclFunc, getColor, getOpacity, colori, opacityi;
 
     if(containerIn.colorscale !== undefined) {
-        sclFunc = makeScaleFunction(containerIn.colorscale, {
-            cmin: containerIn.cmin,
-            cmax: containerIn.cmax
-        });
+        sclFunc = Colorscale.makeColorScaleFunc(
+            Colorscale.extractScale(
+                containerIn.colorscale,
+                containerIn.cmin,
+                containerIn.cmax
+            )
+        );
     }
     else sclFunc = validateColor;
 

src/traces/choropleth/plot.js

@@ -15,8 +15,8 @@ var Axes = require('../../plots/cartesian/axes');
 var Fx = require('../../plots/cartesian/graph_interact');
 var Color = require('../../components/color');
 var Drawing = require('../../components/drawing');
+var Colorscale = require('../../components/colorscale');
 
-var makeScaleFunction = require('../../components/colorscale/make_scale_function');
 var getTopojsonFeatures = require('../../lib/topojson_utils').getTopojsonFeatures;
 var locationToFeature = require('../../lib/geo_location_utils').locationToFeature;
 var arrayToCalcItem = require('../../lib/array_to_calc_item');
@@ -152,10 +152,13 @@ plotChoropleth.style = function(geo) {
                 marker = trace.marker || {},
                 markerLine = marker.line || {};
 
-            var sclFunc = makeScaleFunction(trace.colorscale, {
-                cmin: trace.zmin,
-                cmax: trace.zmax
-            });
+            var sclFunc = Colorscale.makeColorScaleFunc(
+                Colorscale.extractScale(
+                    trace.colorscale,
+                    trace.zmin,
+                    trace.zmax
+                )
+            );
 
             s.selectAll('path.choroplethlocation')
                 .each(function(pt) {

src/traces/contour/make_color_map.js

@@ -10,7 +10,7 @@
 'use strict';
 
 var d3 = require('d3');
-var makeScaleFunction = require('../../components/colorscale/make_scale_function');
+var Colorscale = require('../../components/colorscale');
 
 module.exports = function makeColorMap(trace) {
     var contours = trace.contours,
@@ -67,9 +67,10 @@ module.exports = function makeColorMap(trace) {
         }
     }
 
-    return makeScaleFunction(scl, {
+    return Colorscale.makeColorScaleFunc({
         domain: domain,
         range: range,
+    }, {
         noNumericCheck: true
     });
 };

src/traces/heatmap/colorbar.js

@@ -13,7 +13,7 @@ var isNumeric = require('fast-isnumeric');
 
 var Lib = require('../../lib');
 var Plots = require('../../plots/plots');
-var makeScaleFunction = require('../../components/colorscale/make_scale_function');
+var Colorscale = require('../../components/colorscale');
 var drawColorbar = require('../../components/colorbar/draw');
 
 
@@ -34,11 +34,14 @@ module.exports = function colorbar(gd, cd) {
     }
 
     var cb = cd[0].t.cb = drawColorbar(gd, cbId);
-    var sclFunc = makeScaleFunction(trace.colorscale, {
-        cmin: zmin,
-        cmax: zmax,
-        noNumericCheck: true
-    });
+    var sclFunc = Colorscale.makeColorScaleFunc(
+        Colorscale.extractScale(
+            trace.colorscale,
+            zmin,
+            zmax
+        ),
+        { noNumericCheck: true }
+    );
 
     cb.fillcolor(sclFunc)
         .filllevels({start: zmin, end: zmax, size: (zmax - zmin) / 254})

src/traces/heatmap/plot.js

@@ -13,8 +13,8 @@ var tinycolor = require('tinycolor2');
 
 var Registry = require('../../registry');
 var Lib = require('../../lib');
+var Colorscale = require('../../components/colorscale');
 var xmlnsNamespaces = require('../../constants/xmlns_namespaces');
-var makeScaleFunction = require('../../components/colorscale/make_scale_function');
 
 var maxRowLength = require('./max_row_length');
 
@@ -166,12 +166,14 @@ function plotOne(gd, plotinfo, cd) {
     canvas.height = canvasH;
     var context = canvas.getContext('2d');
 
-    var sclFunc = makeScaleFunction(trace.colorscale, {
-        cmin: trace.zmin,
-        cmax: trace.zmax,
-        noNumericCheck: true,
-        returnArray: true
-    });
+    var sclFunc = Colorscale.makeColorScaleFunc(
+        Colorscale.extractScale(
+            trace.colorscale,
+            trace.zmin,
+            trace.zmax
+        ),
+        { noNumericCheck: true, returnArray: true }
+    );
 
     // map brick boundaries to image pixels
     var xpx,

src/traces/scatter/colorbar.js

@@ -13,7 +13,7 @@ var isNumeric = require('fast-isnumeric');
 
 var Lib = require('../../lib');
 var Plots = require('../../plots/plots');
-var makeScaleFunction = require('../../components/colorscale/make_scale_function');
+var Colorscale = require('../../components/colorscale');
 var drawColorbar = require('../../components/colorbar/draw');
 
 
@@ -40,11 +40,14 @@ module.exports = function colorbar(gd, cd) {
     if(!isNumeric(cmax)) cmax = Lib.aggNums(Math.max, null, vals);
 
     var cb = cd[0].t.cb = drawColorbar(gd, cbId);
-    var sclFunc = makeScaleFunction(marker.colorscale, {
-        cmin: cmin,
-        cmax: cmax,
-        noNumericCheck: true
-    });
+    var sclFunc = Colorscale.makeColorScaleFunc(
+        Colorscale.extractScale(
+            marker.colorscale,
+            cmin,
+            cmax
+        ),
+        { noNumericCheck: true }
+    );
 
     cb.fillcolor(sclFunc)
         .filllevels({start: cmin, end: cmax, size: (cmax - cmin) / 254})