(#6) Added thresholding for opacity values

Author: s1hofmann

index.js

@@ -17,7 +17,12 @@ function bitmap(width, height, byteWidth, bitsPerPixel, bytesPerPixel, image) {
   };
 }
 
-module.exports.screen.highlight = libnut.highlight;
+module.exports.screen.highlight = function(x, y, width, height, duration, opacity) {
+  let highlightOpacity = (opacity < 0) ? 0 : opacity;
+  highlightOpacity = (highlightOpacity > 1) ? 1 : highlightOpacity;
+
+  libnut.highlight(x, y, width, height, duration, highlightOpacity);
+}
 
 module.exports.screen.capture = function(x, y, width, height) {
   //If coords have been passed, use them.