Fix Tetris movement: Add shift modifier

public/assets/scripts/haxxor.js

@@ -7,6 +7,9 @@ const REMOTE_UPDATE_PATH =
 
 ("use strict");
 function createTetris() {
+
+  let keyMap = {};
+
   var tetrominos = [
     {
       // box
@@ -183,25 +186,42 @@ function createTetris() {
 
     var self = this;
 
+    window.addEventListener("keyup", function(e) {
+      keyMap[e.code] = e.type == 'keydown';
+    });
+
     window.addEventListener("keydown", function (e) {
-      switch (e.keyCode) {
+      keyMap[e.code] = e.type == 'keydown';
-        case 37:
+      switch (e.code) {
+        case "ArrowLeft":
+          if (keyMap["ShiftLeft"] || keyMap["ShiftRight"]) {
+            if (self.checkMovement(curPiece, -2, 0)) {
+              curPiece.x -= 2;
+            };
+            break
+          }
           if (self.checkMovement(curPiece, -1, 0)) {
-            curPiece.x--;
+            curPiece.x -= 1;
           } 
           break;
-        case 39:
+        case "ArrowRight":
+          if (keyMap["ShiftLeft"] || keyMap["ShiftRight"]) {
+            if (self.checkMovement(curPiece, 2, 0)) {
+              curPiece.x += 2;
+            }
+            break;
+          }
           if (self.checkMovement(curPiece, 1, 0)) {
-            curPiece.x++;
+            curPiece.x += 1;
           }
           break;
-        case 40:
+        case "ArrowDown":
           if (self.checkMovement(curPiece, 0, 1)) {
             curPiece.y++;
           }
           break;
-        case 32:
+        case "ArrowUp":
-        case 38:
+        case "Space":
           curPiece.data = self.rotateTetrimono(curPiece);
           break;
       }
@@ -231,8 +251,8 @@ function createTetris() {
     } else {
       if (Date.now() > this.lastMove) {
         this.lastMove = Date.now() + this.curSpeed;
-        if (this.checkMovement(curPiece, 0, 1)) {
+        if (this.checkMovement(curPiece, 0, 0.5)) {
-          curPiece.y++;
+          curPiece.y += 0.5;
         } else {
           this.fillBoard(curPiece);
           this.newTetromino();