summaryrefslogtreecommitdiff
path: root/heap/ebus/webapp/static/lib/flot-0.7/jquery.flot.fillbetween.js
blob: 69700e79ce669e9788a6397af174dc2f8475febb (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
/*
Flot plugin for computing bottoms for filled line and bar charts.

The case: you've got two series that you want to fill the area
between. In Flot terms, you need to use one as the fill bottom of the
other. You can specify the bottom of each data point as the third
coordinate manually, or you can use this plugin to compute it for you.

In order to name the other series, you need to give it an id, like this

  var dataset = [
       { data: [ ... ], id: "foo" } ,         // use default bottom
       { data: [ ... ], fillBetween: "foo" }, // use first dataset as bottom
       ];

  $.plot($("#placeholder"), dataset, { line: { show: true, fill: true }});

As a convenience, if the id given is a number that doesn't appear as
an id in the series, it is interpreted as the index in the array
instead (so fillBetween: 0 can also mean the first series).
  
Internally, the plugin modifies the datapoints in each series. For
line series, extra data points might be inserted through
interpolation. Note that at points where the bottom line is not
defined (due to a null point or start/end of line), the current line
will show a gap too. The algorithm comes from the jquery.flot.stack.js
plugin, possibly some code could be shared.
*/

(function ($) {
    var options = {
        series: { fillBetween: null } // or number
    };
    
    function init(plot) {
        function findBottomSeries(s, allseries) {
            var i;
            for (i = 0; i < allseries.length; ++i) {
                if (allseries[i].id == s.fillBetween)
                    return allseries[i];
            }

            if (typeof s.fillBetween == "number") {
                i = s.fillBetween;
            
                if (i < 0 || i >= allseries.length)
                    return null;

                return allseries[i];
            }
            
            return null;
        }
        
        function computeFillBottoms(plot, s, datapoints) {
            if (s.fillBetween == null)
                return;

            var other = findBottomSeries(s, plot.getData());
            if (!other)
                return;

            var ps = datapoints.pointsize,
                points = datapoints.points,
                otherps = other.datapoints.pointsize,
                otherpoints = other.datapoints.points,
                newpoints = [],
                px, py, intery, qx, qy, bottom,
                withlines = s.lines.show,
                withbottom = ps > 2 && datapoints.format[2].y,
                withsteps = withlines && s.lines.steps,
                fromgap = true,
                i = 0, j = 0, l;

            while (true) {
                if (i >= points.length)
                    break;

                l = newpoints.length;

                if (points[i] == null) {
                    // copy gaps
                    for (m = 0; m < ps; ++m)
                        newpoints.push(points[i + m]);
                    i += ps;
                }
                else if (j >= otherpoints.length) {
                    // for lines, we can't use the rest of the points
                    if (!withlines) {
                        for (m = 0; m < ps; ++m)
                            newpoints.push(points[i + m]);
                    }
                    i += ps;
                }
                else if (otherpoints[j] == null) {
                    // oops, got a gap
                    for (m = 0; m < ps; ++m)
                        newpoints.push(null);
                    fromgap = true;
                    j += otherps;
                }
                else {
                    // cases where we actually got two points
                    px = points[i];
                    py = points[i + 1];
                    qx = otherpoints[j];
                    qy = otherpoints[j + 1];
                    bottom = 0;

                    if (px == qx) {
                        for (m = 0; m < ps; ++m)
                            newpoints.push(points[i + m]);

                        //newpoints[l + 1] += qy;
                        bottom = qy;
                        
                        i += ps;
                        j += otherps;
                    }
                    else if (px > qx) {
                        // we got past point below, might need to
                        // insert interpolated extra point
                        if (withlines && i > 0 && points[i - ps] != null) {
                            intery = py + (points[i - ps + 1] - py) * (qx - px) / (points[i - ps] - px);
                            newpoints.push(qx);
                            newpoints.push(intery)
                            for (m = 2; m < ps; ++m)
                                newpoints.push(points[i + m]);
                            bottom = qy; 
                        }

                        j += otherps;
                    }
                    else { // px < qx
                        if (fromgap && withlines) {
                            // if we come from a gap, we just skip this point
                            i += ps;
                            continue;
                        }
                            
                        for (m = 0; m < ps; ++m)
                            newpoints.push(points[i + m]);
                        
                        // we might be able to interpolate a point below,
                        // this can give us a better y
                        if (withlines && j > 0 && otherpoints[j - otherps] != null)
                            bottom = qy + (otherpoints[j - otherps + 1] - qy) * (px - qx) / (otherpoints[j - otherps] - qx);

                        //newpoints[l + 1] += bottom;
                        
                        i += ps;
                    }

                    fromgap = false;
                    
                    if (l != newpoints.length && withbottom)
                        newpoints[l + 2] = bottom;
                }

                // maintain the line steps invariant
                if (withsteps && l != newpoints.length && l > 0
                    && newpoints[l] != null
                    && newpoints[l] != newpoints[l - ps]
                    && newpoints[l + 1] != newpoints[l - ps + 1]) {
                    for (m = 0; m < ps; ++m)
                        newpoints[l + ps + m] = newpoints[l + m];
                    newpoints[l + 1] = newpoints[l - ps + 1];
                }
            }

            datapoints.points = newpoints;
        }
        
        plot.hooks.processDatapoints.push(computeFillBottoms);
    }
    
    $.plot.plugins.push({
        init: init,
        options: options,
        name: 'fillbetween',
        version: '1.0'
    });
})(jQuery);