added rasterization functions

main.js

@@ -9,3 +9,13 @@ const targetColor = config.targetColor;
 
 const tolerance = config.tolerance;
 
+
+function rasterize(x, y, width){ //scale to image
+    return (x + y * width);
+}
+function deRasterize(i, width){
+    return ({
+        y: Math.floor(i/width),
+        x: i % width
+    });
+}