fix corner radous for Label shape

CHANGELOG.md

@@ -7,6 +7,7 @@ This project adheres to [Semantic Versioning](http://semver.org/).
 ### Fixed
 - correct `Konva.Arrow` drawing. Now it works better.
 - Better support for dragging when mouse out of stage
+- Better corner radius for `Label` shape
 
 ### Added
 - event delegation. You can use it in this way: `layer.on('click', 'Circle', handler);`

konva.js

@@ -15767,10 +15767,14 @@ var Konva = {};
                 pointerDirection = this.getPointerDirection(),
                 pointerWidth = this.getPointerWidth(),
                 pointerHeight = this.getPointerHeight(),
-                cornerRadius = this.getCornerRadius();
+                cornerRadius = Math.min(this.getCornerRadius, width / 2, height / 2);
 
             context.beginPath();
-            context.moveTo(0, 0);
+            if (!cornerRadius) {
+                context.moveTo(0, 0);
+            } else {
+                context.moveTo(cornerRadius, 0);
+            }
 
             if (pointerDirection === UP) {
                 context.lineTo((width - pointerWidth) / 2, 0);

src/plugins/Label.js

@@ -185,10 +185,14 @@
                 pointerDirection = this.getPointerDirection(),
                 pointerWidth = this.getPointerWidth(),
                 pointerHeight = this.getPointerHeight(),
-                cornerRadius = this.getCornerRadius();
+                cornerRadius = Math.min(this.getCornerRadius, width / 2, height / 2);
 
             context.beginPath();
-            context.moveTo(0, 0);
+            if (!cornerRadius) {
+                context.moveTo(0, 0);
+            } else {
+                context.moveTo(cornerRadius, 0);
+            }
 
             if (pointerDirection === UP) {
                 context.lineTo((width - pointerWidth) / 2, 0);