reduce the number of calls to compute newSvg width & height

Author: archmoj

src/lib/svg_text_utils.js

@@ -11,10 +11,6 @@ var LINE_SPACING = require('../constants/alignment').LINE_SPACING;
 
 // text converter
 
-function getSize(_selection, _dimension) {
-    return _selection.node().getBoundingClientRect()[_dimension];
-}
-
 var FIND_TEX = /([^$]*)([$]+[^$]*[$]+)([^$]*)/;
 
 exports.convertToTspans = function(_context, gd, _callback) {
@@ -109,16 +105,17 @@ exports.convertToTspans = function(_context, gd, _callback) {
                 var g = newSvg.select('g');
                 g.attr({fill: fill, stroke: fill});
 
-                var newSvgW = getSize(g, 'width');
-                var newSvgH = getSize(g, 'height');
+                var gBB = g.node().getBoundingClientRect();
+                var newSvgW = gBB.width;
+                var newSvgH = gBB.height;
 
                 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 || getSize(_context, 'height');
+                var textHeight = fontSize || _context.node().getBoundingClientRect().height;
                 var dy = -textHeight / 4;
 
                 if(svgClass[0] === 'y') {