Projects, 01-06 completed

3 files changed, 202 insertions, 0 deletions

diff --git a/projects/09/Square/Main.jack b/projects/09/Square/Main.jack
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+++ b/projects/09/Square/Main.jack
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+// This file is part of www.nand2tetris.org

+// and the book "The Elements of Computing Systems"

+// by Nisan and Schocken, MIT Press.

+// File name: projects/09/Square/Main.jack

+

+/** Initializes a new Square Dance game and starts running it. */

+class Main {

+    function void main() {

+        var SquareGame game;

+        let game = SquareGame.new();

+        do game.run();

+        do game.dispose();

+        return;

+    }

+}

diff --git a/projects/09/Square/Square.jack b/projects/09/Square/Square.jack
new file mode 100644
index 0000000..38066e5
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+++ b/projects/09/Square/Square.jack
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+// This file is part of www.nand2tetris.org
+// and the book "The Elements of Computing Systems"
+// by Nisan and Schocken, MIT Press.
+// File name: projects/09/Square/Square.jack
+
+/** Implements a graphical square. */
+class Square {
+
+   field int x, y; // screen location of the square's top-left corner
+   field int size; // length of this square, in pixels
+
+   /** Constructs a new square with a given location and size. */
+   constructor Square new(int Ax, int Ay, int Asize) {
+      let x = Ax;
+      let y = Ay;
+      let size = Asize;
+      do draw();
+      return this;
+   }
+
+   /** Disposes this square. */
+   method void dispose() {
+      do Memory.deAlloc(this);
+      return;
+   }
+
+   /** Draws the square on the screen. */
+   method void draw() {
+      do Screen.setColor(true);
+      do Screen.drawRectangle(x, y, x + size, y + size);
+      return;
+   }
+
+   /** Erases the square from the screen. */
+   method void erase() {
+      do Screen.setColor(false);
+      do Screen.drawRectangle(x, y, x + size, y + size);
+      return;
+   }
+
+    /** Increments the square size by 2 pixels. */
+   method void incSize() {
+      if (((y + size) < 254) & ((x + size) < 510)) {
+         do erase();
+         let size = size + 2;
+         do draw();
+      }
+      return;
+   }
+
+   /** Decrements the square size by 2 pixels. */
+   method void decSize() {
+      if (size > 2) {
+         do erase();
+         let size = size - 2;
+         do draw();
+      }
+      return;
+   }
+
+   /** Moves the square up by 2 pixels. */
+   method void moveUp() {
+      if (y > 1) {
+         do Screen.setColor(false);
+         do Screen.drawRectangle(x, (y + size) - 1, x + size, y + size);
+         let y = y - 2;
+         do Screen.setColor(true);
+         do Screen.drawRectangle(x, y, x + size, y + 1);
+      }
+      return;
+   }
+
+   /** Moves the square down by 2 pixels. */
+   method void moveDown() {
+      if ((y + size) < 254) {
+         do Screen.setColor(false);
+         do Screen.drawRectangle(x, y, x + size, y + 1);
+         let y = y + 2;
+         do Screen.setColor(true);
+         do Screen.drawRectangle(x, (y + size) - 1, x + size, y + size);
+      }
+      return;
+   }
+
+   /** Moves the square left by 2 pixels. */
+   method void moveLeft() {
+      if (x > 1) {
+         do Screen.setColor(false);
+         do Screen.drawRectangle((x + size) - 1, y, x + size, y + size);
+         let x = x - 2;
+         do Screen.setColor(true);
+         do Screen.drawRectangle(x, y, x + 1, y + size);
+      }
+      return;
+   }
+
+   /** Moves the square right by 2 pixels. */
+   method void moveRight() {
+      if ((x + size) < 510) {
+         do Screen.setColor(false);
+         do Screen.drawRectangle(x, y, x + 1, y + size);
+         let x = x + 2;
+         do Screen.setColor(true);
+         do Screen.drawRectangle((x + size) - 1, y, x + size, y + size);
+      }
+      return;
+   }
+}
diff --git a/projects/09/Square/SquareGame.jack b/projects/09/Square/SquareGame.jack
new file mode 100644
index 0000000..02393e2
--- /dev/null
+++ b/projects/09/Square/SquareGame.jack
@@ -0,0 +1,79 @@
+// This file is part of www.nand2tetris.org

+// and the book "The Elements of Computing Systems"

+// by Nisan and Schocken, MIT Press.

+// File name: projects/09/Square/SquareGame.jack

+

+/**

+ * Implements the Square Dance game.

+ * This simple game allows the user to move a black square around

+ * the screen, and change the square's size during the movement.

+ * When the game starts, a square of 30 by 30 pixels is shown at the

+ * top-left corner of the screen. The user controls the square as follows.

+ * The 4 arrow keys are used to move the square up, down, left, and right.

+ * The 'z' and 'x' keys are used, respectively, to decrement and increment

+ * the square's size. The 'q' key is used to quit the game.

+ */

+

+class SquareGame {

+   field Square square; // the square of this game

+   field int direction; // the square's current direction: 

+                        // 0=none, 1=up, 2=down, 3=left, 4=right

+

+   /** Constructs a new Square Game. */

+   constructor SquareGame new() {

+      // Creates a 30 by 30 pixels square and positions it at the top-left

+      // of the screen.

+      let square = Square.new(0, 0, 30);

+      let direction = 0;  // initial state is no movement

+      return this;

+   }

+

+   /** Disposes this game. */

+   method void dispose() {

+      do square.dispose();

+      do Memory.deAlloc(this);

+      return;

+   }

+

+   /** Moves the square in the current direction. */

+   method void moveSquare() {

+      if (direction = 1) { do square.moveUp(); }

+      if (direction = 2) { do square.moveDown(); }

+      if (direction = 3) { do square.moveLeft(); }

+      if (direction = 4) { do square.moveRight(); }

+      do Sys.wait(5);  // delays the next movement

+      return;

+   }

+

+   /** Runs the game: handles the user's inputs and moves the square accordingly */

+   method void run() {

+      var char key;  // the key currently pressed by the user

+      var boolean exit;

+      let exit = false;

+      

+      while (~exit) {

+         // waits for a key to be pressed

+         while (key = 0) {

+            let key = Keyboard.keyPressed();

+            do moveSquare();

+         }

+         if (key = 81)  { let exit = true; }     // q key

+         if (key = 90)  { do square.decSize(); } // z key

+         if (key = 88)  { do square.incSize(); } // x key

+         if (key = 131) { let direction = 1; }   // up arrow

+         if (key = 133) { let direction = 2; }   // down arrow

+         if (key = 130) { let direction = 3; }   // left arrow

+         if (key = 132) { let direction = 4; }   // right arrow

+

+         // waits for the key to be released

+         while (~(key = 0)) {

+            let key = Keyboard.keyPressed();

+            do moveSquare();

+         }

+     } // while

+     return;

+   }

+}

+

+

+