Fix label vertical alignment on vertical scales (#5248)

diff --git a/src/core/core.scale.js b/src/core/core.scale.js
index f79dbee8009ddca0abc4642e337513e6fe4d3e03..1996c6c894d7f5ae61202183f322153f5271249c 100644 (file)
--- a/src/core/core.scale.js
+++ b/src/core/core.scale.js
@@ -857,11 +857,15 @@ module.exports = function(Chart) {
 
                                        var label = itemToDraw.label;
                                        if (helpers.isArray(label)) {
-                                               for (var i = 0, y = 0; i < label.length; ++i) {
+                                               var lineCount = label.length;
+                                               var lineHeight = tickFont.size * 1.5;
+                                               var y = me.isHorizontal() ? 0 : -lineHeight * (lineCount - 1) / 2;
+
+                                               for (var i = 0; i < lineCount; ++i) {
                                                        // We just make sure the multiline element is a string here..
                                                        context.fillText('' + label[i], 0, y);
                                                        // apply same lineSpacing as calculated @ L#320
-                                                       y += (tickFont.size * 1.5);
+                                                       y += lineHeight;
                                                }
                                        } else {
                                                context.fillText(label, 0, 0);