add new errorbar plot (now draws in the trace layers)

Author: etpinard

src/components/errorbars/plot.js

@@ -0,0 +1,115 @@
+/**
+* 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';
+
+var d3 = require('d3');
+var isNumeric = require('fast-isnumeric');
+
+var Lib = require('../../lib');
+var subTypes = require('../../traces/scatter/subtypes');
+
+
+module.exports = function plot(traces, plotinfo) {
+    var xa = plotinfo.x(),
+        ya = plotinfo.y();
+
+    traces.each(function(d) {
+        var trace = d[0].trace,
+            xObj = trace.error_x,
+            yObj = trace.error_y;
+
+        var sparse = (
+            subTypes.hasMarkers(trace) &&
+            trace.marker.maxdisplayed > 0
+        );
+
+        if(!yObj.visible && !xObj.visible) return;
+
+        var errorbars = d3.select(this).selectAll('g.errorbar')
+            .data(Lib.identity);
+
+        errorbars.enter().append('g')
+            .classed('errorbar', true);
+
+        errorbars.each(function(d) {
+            var errorbar = d3.select(this);
+            var coords = errorCoords(d, xa, ya);
+
+            if(sparse && !d.vis) return;
+
+            var path;
+
+            if(yObj.visible && isNumeric(coords.x) &&
+                    isNumeric(coords.yh) &&
+                    isNumeric(coords.ys)) {
+                var yw = yObj.width;
+
+                path = 'M' + (coords.x - yw) + ',' +
+                    coords.yh + 'h' + (2 * yw) + // hat
+                    'm-' + yw + ',0V' + coords.ys; // bar
+
+                if(!coords.noYS) path += 'm-' + yw +',0h' + (2 * yw); // shoe
+
+                errorbar.append('path')
+                    .classed('yerror', true)
+                    .attr('d', path);
+            }
+
+            if(xObj.visible && isNumeric(coords.y) &&
+                    isNumeric(coords.xh) &&
+                    isNumeric(coords.xs)) {
+                var xw = (xObj.copy_ystyle ? yObj : xObj).width;
+
+                path = 'M' + coords.xh + ',' +
+                    (coords.y - xw) + 'v' + (2 * xw) + // hat
+                    'm0,-' + xw + 'H' + coords.xs; // bar
+
+                if(!coords.noXS) path += 'm0,-' + xw + 'v' + (2 * xw); // shoe
+
+                errorbar.append('path')
+                    .classed('xerror', true)
+                    .attr('d', path);
+            }
+        });
+    });
+};
+
+// compute the coordinates of the error-bar objects
+function errorCoords(d, xa, ya) {
+    var out = {
+        x: xa.c2p(d.x),
+        y: ya.c2p(d.y)
+    };
+
+    // calculate the error bar size and hat and shoe locations
+    if(d.yh !== undefined) {
+        out.yh = ya.c2p(d.yh);
+        out.ys = ya.c2p(d.ys);
+
+        // if the shoes go off-scale (ie log scale, error bars past zero)
+        // clip the bar and hide the shoes
+        if(!isNumeric(out.ys)) {
+            out.noYS = true;
+            out.ys = ya.c2p(d.ys, true);
+        }
+    }
+
+    if(d.xh !== undefined) {
+        out.xh = xa.c2p(d.xh);
+        out.xs = xa.c2p(d.xs);
+
+        if(!isNumeric(out.xs)) {
+            out.noXS = true;
+            out.xs = xa.c2p(d.xs, true);
+        }
+    }
+
+    return out;
+}