connect.js

/**
* Copyright 2012-2018, 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';

var isNumeric = require('fast-isnumeric');

var aggNums = require('../../lib').aggNums;
var Colorscale = require('../colorscale');
var drawColorbar = require('./draw');

/**
 * connectColorbar: create a colorbar from a trace, using its module to
 *   describe the connection.
 *
 * @param {DOM element} gd
 *
 * @param {Array} cd
 *   calcdata entry for this trace. cd[0].trace is the trace itself, and the
 *   colorbar object will be stashed in cd[0].t.cb
 *
 * @param {object|function} moduleOpts
 *   may be a function(gd, cd) to override the standard handling below. If
 *   an object, should have these keys:
 * @param {Optional(string)} moduleOpts.container
 *   name of the container inside the trace where the colorbar and colorscale
 *   attributes live (ie 'marker', 'line') - omit if they're at the trace root.
 * @param {string} moduleOpts.min
 *   name of the attribute holding the value of the minimum color
 * @param {string} moduleOpts.max
 *   name of the attribute holding the value of the maximum color
 * @param {Optional(string)} moduleOpts.vals
 *   name of the attribute holding the (numeric) color data
 *   used only if min/max fail. May be omitted if these are always
 *   pre-calculated.
 */
module.exports = function connectColorbar(gd, cd, moduleOpts) {
    if(typeof moduleOpts === 'function') return moduleOpts(gd, cd);

    var trace = cd[0].trace;
    var cbId = 'cb' + trace.uid;
    var containerName = moduleOpts.container;
    var container = containerName ? trace[containerName] : trace;

    gd._fullLayout._infolayer.selectAll('.' + cbId).remove();
    if(!container || !container.showscale) return;

    var zmin = container[moduleOpts.min];
    var zmax = container[moduleOpts.max];

    var valAttr = moduleOpts.vals;
    var vals;
    if(Array.isArray(valAttr)) {
        for(var i = 0; i < valAttr.length; i++) {
            vals = container[valAttr[i]];
            if(vals) break;
        }
    }
    else vals = container[valAttr];

    if(vals) {
        if(!isNumeric(zmin)) zmin = aggNums(Math.min, null, vals);
        if(!isNumeric(zmax)) zmax = aggNums(Math.max, null, vals);
    }

    var cb = cd[0].t.cb = drawColorbar(gd, cbId);
    var sclFunc = Colorscale.makeColorScaleFunc(
        Colorscale.extractScale(
            container.colorscale,
            zmin,
            zmax
        ),
        { noNumericCheck: true }
    );

    cb.fillcolor(sclFunc)
        .filllevels({start: zmin, end: zmax, size: (zmax - zmin) / 254})
        .options(container.colorbar)();
};