Merge pull request #5989 from plotly/mathjax-anchor

unified call to position mathjax

Author: archmoj

src/lib/svg_text_utils.js

@@ -112,8 +112,6 @@ exports.convertToTspans = function(_context, gd, _callback) {
                 var x = +_context.attr('x');
                 var y = +_context.attr('y');
 
-                var newX = x - newSvgW *
-                    {start: 0, middle: 0.5, end: 1}[_context.attr('text-anchor') || 'start'];
                 // font baseline is about 1/4 fontSize below centerline
                 var textHeight = fontSize || _context.node().getBoundingClientRect().height;
                 var dy = -textHeight / 4;
@@ -123,15 +121,26 @@ exports.convertToTspans = function(_context, gd, _callback) {
                         transform: 'rotate(' + [-90, x, y] +
                         ')' + strTranslate(-newSvgW / 2, dy - newSvgH / 2)
                     });
-                    newSvg.attr({x: x, y: y});
                 } else if(svgClass[0] === 'l') {
-                    newSvg.attr({x: x, y: dy - (newSvgH / 2)});
+                    y = dy - newSvgH / 2;
                 } else if(svgClass[0] === 'a' && svgClass.indexOf('atitle') !== 0) {
-                    newSvg.attr({x: 0, y: dy});
+                    x = 0;
+                    y = dy;
                 } else {
-                    newSvg.attr({x: newX, y: (y + dy - newSvgH / 2)});
+                    var anchor = _context.attr('text-anchor');
+
+                    x = x - newSvgW * (
+                        anchor === 'middle' ? 0.5 :
+                        anchor === 'end' ? 1 : 0
+                    );
+                    y = y + dy - newSvgH / 2;
                 }
 
+                newSvg.attr({
+                    x: x,
+                    y: y
+                });
+
                 if(_callback) _callback.call(_context, mathjaxGroup);
                 resolve(mathjaxGroup);
             });