diff --git a/js-lib/common.js b/js-lib/common.js
index ef402e7..3dc527c 100644
--- a/js-lib/common.js
+++ b/js-lib/common.js
@@ -37,6 +37,13 @@ ascii.Vector.prototype.add = function(other) {
   return new ascii.Vector(this.x + other.x, this.y + other.y);
 };
 
+/**
+ * @return {ascii.Vector}
+ */
+ascii.Vector.prototype.clone = function() {
+  return new ascii.Vector(this.x, this.y);
+};
+
 /** @return {number} */
 ascii.Vector.prototype.length = function() {
   return Math.sqrt(this.x * this.x + this.y * this.y);
diff --git a/js-lib/state-controller.js b/js-lib/state-controller.js
index 803e6cd..adfd2ea 100644
--- a/js-lib/state-controller.js
+++ b/js-lib/state-controller.js
@@ -2,6 +2,29 @@ goog.provide('ascii.StateController');
 
 goog.require('ascii.Vector');
 
+/** 
+ * Draws a line.
+ */
+function drawLine(state, startPosition, endPosition, clockwise) {
+  var hX1 = Math.min(startPosition.x, endPosition.x);
+  var vY1 = Math.min(startPosition.y, endPosition.y);
+  var hX2 = Math.max(startPosition.x, endPosition.x);
+  var vY2 = Math.max(startPosition.y, endPosition.y);
+
+  var hY = clockwise ? startPosition.y : endPosition.y;
+  var vX = clockwise ? endPosition.x : startPosition.x;
+
+  while (hX1++ < hX2) {
+    state.drawSpecial(new ascii.Vector(hX1, hY));
+  }
+  while (vY1++ < vY2) {
+    state.drawSpecial(new ascii.Vector(vX, vY1));
+  }
+  state.drawSpecial(startPosition);
+  state.drawSpecial(endPosition);
+  state.drawSpecial(new ascii.Vector(vX, hY));
+};
+
 /**
  * Common interface for different drawing functions, e.g. box, line, etc.
  * @interface
@@ -22,45 +45,21 @@ DrawFunction.prototype.end = function(position) {};
 function DrawBox(state) {
   this.state = state;
   /** @type {ascii.Vector} */ this.startPosition = null;
-  /** @type {ascii.Vector} */ this.endPosition = null;
 }
 
 DrawBox.prototype.start = function(position) {
   this.startPosition = position;
-  this.endPosition = position;
-  this.draw();
 };
 DrawBox.prototype.move = function(position) {
   this.endPosition = position;
   this.state.clearDraw();
-  this.draw();
+  drawLine(this.state, this.startPosition, position, true);
+  drawLine(this.state, this.startPosition, position, false);
 };
 DrawBox.prototype.end = function(position) {
   this.state.commitDraw();
 };
 
-/** Draws the currently dragged out box. */
-DrawBox.prototype.draw = function() {
-  var x1 = Math.min(this.startPosition.x, this.endPosition.x);
-  var y1 = Math.min(this.startPosition.y, this.endPosition.y);
-  var x2 = Math.max(this.startPosition.x, this.endPosition.x);
-  var y2 = Math.max(this.startPosition.y, this.endPosition.y);
-
-  this.state.drawSpecial(new ascii.Vector(x1, y1));
-  this.state.drawSpecial(new ascii.Vector(x1, y2));
-  this.state.drawSpecial(new ascii.Vector(x2, y1));
-  this.state.drawSpecial(new ascii.Vector(x2, y2));
-
-
-  for (var x = x1 + 1; x < x2; x++) {
-    this.state.drawSpecial(new ascii.Vector(x, y1));
-    this.state.drawSpecial(new ascii.Vector(x, y2));
-  }
-  for (var y = y1 + 1; y < y2; y++) {
-    this.state.drawSpecial(new ascii.Vector(x1, y));
-    this.state.drawSpecial(new ascii.Vector(x2, y));
-  }
-};
 
 /**
  * @constructor
@@ -70,58 +69,27 @@ DrawBox.prototype.draw = function() {
 function DrawLine(state) {
   this.state = state;
   /** @type {ascii.Vector} */ this.startPosition = null;
-  /** @type {ascii.Vector} */ this.endPosition = null;
 }
 
 DrawLine.prototype.start = function(position) {
   this.startPosition = position;
-  this.endPosition = position;
-  this.draw();
 };
 DrawLine.prototype.move = function(position) {
-  this.endPosition = position;
   this.state.clearDraw();
-  this.draw();
+
+  // Try to infer line orientation.
+  var startContext = this.state.getContext(this.startPosition);
+  var endContext = this.state.getContext(position);
+  var clockwise = (startContext.up && startContext.down) ||
+      (endContext.left && endContext.right);
+
+  drawLine(this.state, this.startPosition, position, clockwise);
 };
+
 DrawLine.prototype.end = function(position) {
   this.state.commitDraw();
 };
 
-/** 
- * Draws the currently dragged out line.
- */
-DrawLine.prototype.draw = function() {
-  var upStart = this.state.isSpecial(
-      this.startPosition.add(new ascii.Vector(0, -1)));
-  var downStart = this.state.isSpecial(
-      this.startPosition.add(new ascii.Vector(0, 1)));
-  var leftEnd = this.state.isSpecial(
-      this.endPosition.add(new ascii.Vector(-1, 0)));
-  var rightEnd = this.state.isSpecial(
-      this.endPosition.add(new ascii.Vector(1, 0)));
-
-  // Look at the start and end contexts to infer line orientation.
-  var isClockwise = (upStart && downStart) || (leftEnd && rightEnd);
-
-  var hX1 = Math.min(this.startPosition.x, this.endPosition.x);
-  var vY1 = Math.min(this.startPosition.y, this.endPosition.y);
-  var hX2 = Math.max(this.startPosition.x, this.endPosition.x);
-  var vY2 = Math.max(this.startPosition.y, this.endPosition.y);
-
-  var hY = isClockwise ? this.startPosition.y : this.endPosition.y;
-  var vX = isClockwise ? this.endPosition.x : this.startPosition.x;
-
-  while (hX1++ < hX2) {
-    this.state.drawSpecial(new ascii.Vector(hX1, hY));
-  }
-  while (vY1++ < vY2) {
-    this.state.drawSpecial(new ascii.Vector(vX, vY1));
-  }
-  this.state.drawSpecial(new ascii.Vector(this.startPosition.x, this.startPosition.y));
-  this.state.drawSpecial(new ascii.Vector(this.endPosition.x, this.endPosition.y));
-  this.state.drawSpecial(new ascii.Vector(vX, hY));
-};
-
 /**
  * @constructor
  * @implements {DrawFunction}
@@ -143,6 +111,84 @@ DrawFreeform.prototype.move = function(position) {
 DrawFreeform.prototype.end = function(position) {
 };
 
+/**
+ * @constructor
+ * @implements {DrawFunction}
+ * @param {ascii.State} state
+ */
+function DrawMove(state) {
+  this.state = state;
+  this.ends = null;
+}
+
+DrawMove.prototype.start = function(position) {
+  var context = this.state.getContext(position);
+  var directions = [
+    new ascii.Vector(1, 0),
+    new ascii.Vector(-1, 0),
+    new ascii.Vector(0, 1),
+    new ascii.Vector(0, -1) ];
+
+  var ends = [];
+  for (var i in directions) {
+    var midPoint = this.followLine(position, directions[i]);
+    // Clockwise is a lie, it is true if we move vertically first.
+    var clockwise = (directions[i].x != 0);
+    // Ignore any directions that didn't go anywhere.
+    if (position.equals(midPoint)) {
+      continue;
+    }
+    var midPointContext = this.state.getContext(midPoint);
+    // Special case, a straight line with no turns.
+    if ((midPointContext.left + midPointContext.right +
+        midPointContext.up + midPointContext.down) == 1) {
+      ends.push({position: midPoint, clockwise: clockwise});
+      continue;
+    }
+    // Continue following lines from the midpoint.
+    for (var j in directions) {
+      if (directions[i].add(directions[j]).length() == 0) {
+        // Don't go back on ourselves.
+        continue;
+      }
+      var end = this.followLine(midPoint, directions[j]);
+      // Ignore any directions that didn't go anywhere.
+      if (midPoint.equals(end)) {
+        continue;
+      }
+      ends.push({position: end, clockwise: clockwise});
+    }
+  }
+  this.ends = ends;
+};
+
+DrawMove.prototype.move = function(position) {
+  this.state.clearDraw();
+  for (var i in this.ends) {
+    drawLine(this.state, position, this.ends[i].position, this.ends[i].clockwise);
+  }
+};
+
+DrawMove.prototype.end = function(position) {
+  this.state.commitDraw();
+};
+
+DrawMove.prototype.followLine = function(startPosition, direction) {
+  var endPosition = startPosition.clone();
+  while (true) {
+    var nextEnd = endPosition.add(direction);
+    if (!this.state.isSpecial(nextEnd)) {
+      return endPosition;
+    }
+    endPosition = nextEnd;
+    var context = this.state.getContext(nextEnd);
+    if (!(context.left && context.right && !context.up && !context.down) &&
+        !(!context.left && !context.right && context.up && context.down)) {
+      return endPosition;
+    }
+  }
+};
+
 /**
  * Handles management of the diagram state. Input events are cleaned in the
  * parent controller and passed down to this class for dealing with drawing.
@@ -169,6 +215,10 @@ ascii.StateController = function(state) {
   $('#erase-button').click(function(e) {
     this.drawFunction = new DrawFreeform(state, null);
   }.bind(this));
+
+  $('#move-button').click(function(e) {
+    this.drawFunction = new DrawMove(state);
+  }.bind(this));
 };
 
 /**
diff --git a/js-lib/state.js b/js-lib/state.js
index 58504ee..f6bfdbd 100644
--- a/js-lib/state.js
+++ b/js-lib/state.js
@@ -21,6 +21,19 @@ ascii.Cell.prototype.getDrawValue = function() {
   return (this.scratchValue != null ? this.scratchValue : this.value);
 };
 
+/**
+ * The context for a cell, i.e. the status of the cells around it.
+ *
+ * @param {boolean} left, right, up, down
+ * @constructor
+ */
+ascii.CellContext = function(left, right, up, down) {
+  /** @type {boolean} */ this.left = left;
+  /** @type {boolean} */ this.right = right;
+  /** @type {boolean} */ this.up = up;
+  /** @type {boolean} */ this.down = down;
+};
+
 /**
  * Holds the entire state of the diagram as a 2D array of cells.
  *
@@ -118,21 +131,30 @@ ascii.State.prototype.getDrawValue = function(position) {
   }
 
   // Magic time.
+  var context = this.getContext(position);
+  
+  if (context.left && context.right && !context.up && !context.down) {
+    return SPECIAL_LINE_H;
+  }
+  if (!context.left && !context.right && context.up && context.down) {
+    return SPECIAL_LINE_V;
+  }
+  if (context.left && context.right && context.up && context.down) {
+    return SPECIAL_LINE_H;
+  }
+  return SPECIAL_VALUE;
+};
+
+/**
+ * @param {ascii.Vector} position
+ * @return {ascii.CellContext}
+ */
+ascii.State.prototype.getContext = function(position) {
   var left = this.isSpecial(position.add(new ascii.Vector(-1, 0)));
   var right = this.isSpecial(position.add(new ascii.Vector(1, 0)));
   var up = this.isSpecial(position.add(new ascii.Vector(0, -1)));
   var down = this.isSpecial(position.add(new ascii.Vector(0, 1)));
-  
-  if (left && right && !up && !down) {
-    return SPECIAL_LINE_H;
-  }
-  if (!left && !right && up && down) {
-    return SPECIAL_LINE_V;
-  }
-  if (left && right && up && down) {
-    return SPECIAL_LINE_H;
-  }
-  return SPECIAL_VALUE;
+  return new ascii.CellContext(left, right, up, down);
 };
 
 /**
diff --git a/root.html b/root.html
index 83880ce..a971f8d 100644
--- a/root.html
+++ b/root.html
@@ -39,6 +39,7 @@ button {
   <button id="line-button">Line</button>
   <button id="freeform-button">Freeform</button>
   <button id="erase-button">Erase</button>
+  <button id="move-button">Move</button>
 </div>
 <canvas id="ascii-canvas"></canvas>
 <script src="jquery-1.9.1.min.js"></script>