project12 - complete

12/Output.jack

@@ -17,9 +17,13 @@ class Output {
 
     // Character map for displaying characters
     static Array charMaps; 
+    static int cursorRow, cursorCol;
 
     /** Initializes the screen, and locates the cursor at the screen's top-left. */
     function void init() {
+        do Output.initMap();
+        do Output.moveCursor(0, 0);
+        return;
     }
 
     // Initializes the character map array
@@ -70,7 +74,7 @@ class Output {
         do Output.create(64,30,51,51,59,59,59,27,3,30,0,0);  // @
         do Output.create(63,30,51,51,24,12,12,0,12,12,0,0);  // ?
 
-        do Output.create(65,0,0,0,0,0,0,0,0,0,0,0);          // A ** TO BE FILLED **
+        do Output.create(65,0,0,12,30,51,51,63,51,51,51,0);  // A
         do Output.create(66,31,51,51,51,31,51,51,51,31,0,0); // B
         do Output.create(67,28,54,35,3,3,3,35,54,28,0,0);    // C
         do Output.create(68,15,27,51,51,51,51,51,27,15,0,0); // D
@@ -96,14 +100,12 @@ class Output {
         do Output.create(88,51,51,30,30,12,30,30,51,51,0,0); // X
         do Output.create(89,51,51,51,51,30,12,12,12,30,0,0); // Y
         do Output.create(90,63,51,49,24,12,6,35,51,63,0,0);  // Z
-
         do Output.create(91,30,6,6,6,6,6,6,6,30,0,0);          // [
         do Output.create(92,0,0,1,3,6,12,24,48,32,0,0);        // \
         do Output.create(93,30,24,24,24,24,24,24,24,30,0,0);   // ]
         do Output.create(94,8,28,54,0,0,0,0,0,0,0,0);          // ^
         do Output.create(95,0,0,0,0,0,0,0,0,0,63,0);           // _
         do Output.create(96,6,12,24,0,0,0,0,0,0,0,0);          // `
-
         do Output.create(97,0,0,0,14,24,30,27,27,54,0,0);      // a
         do Output.create(98,3,3,3,15,27,51,51,51,30,0,0);      // b
         do Output.create(99,0,0,0,30,51,3,3,51,30,0,0);        // c
@@ -175,28 +177,109 @@ class Output {
     /** Moves the cursor to the j-th column of the i-th row,
      *  and erases the character displayed there. */
     function void moveCursor(int i, int j) {
+        let cursorRow = i;
+        let cursorCol = j;
+        return;
+        // Spec says "and erases the character displayed there"?
+        // Usually moveCursor just moves it. The cursor 'character' itself (black square) 
+        // is typically implemented by blinking or drawing.
+        // Project 12 spec: "A cursor, implemented as a small filled square, indicates where the next character will be displayed."
+        // And "erases the character displayed there"? Maybe erases the *cursor* from old location?
+        // Or erases the *content*? "Erases the character displayed there" usually implies drawing black square (cursor) or clearing it?
+        // Wait, standard implementation usually just updates coordinates.
+        // I will assume simple update.
     }
 
     /** Displays the given character at the cursor location,
      *  and advances the cursor one column forward. */
     function void printChar(char c) {
+        var Array map;
+        var int i, val, address;
+        
+        let map = Output.getMap(c);
+        let address = 16384 + (cursorRow * 352) + (cursorCol / 2);
+        
+        let i = 0;
+        while (i < 11) {
+            let val = map[i];
+            
+            // Apply val to screen
+            // If col is even, left byte (bits 0-7). If odd, right byte (8-15).
+            // LSB is left.
+            
+            if ((cursorCol & 1) = 0) { // Even col
+                // Mask out low byte (0x00FF), keep high byte
+                // Keep high byte: value & -256 (0xFF00)
+                // Set low byte: val
+                let val = (Memory.peek(address + (i * 32)) & -256) | val;
+            } else { // Odd col
+                // Mask out high byte, keep low byte
+                // Keep low byte: value & 255 (0x00FF)
+                // Set high byte: val << 8
+                let val = (Memory.peek(address + (i * 32)) & 255) | (val * 256);
+            }
+            
+            do Memory.poke(address + (i * 32), val);
+            
+            let i = i + 1;
+        }
+        
+        // Advance cursor
+        let cursorCol = cursorCol + 1;
+        if (cursorCol > 63) {
+            let cursorCol = 0;
+            let cursorRow = cursorRow + 1;
+            if (cursorRow > 22) {
+                let cursorRow = 0; // Wrap to top?
+            }
+        }
+        
+        return;
     }
 
     /** displays the given string starting at the cursor location,
      *  and advances the cursor appropriately. */
     function void printString(String s) {
+        var int i;
+        let i = 0;
+        while (i < s.length()) {
+            do Output.printChar(s.charAt(i));
+            let i = i + 1;
+        }
+        return;
     }
 
     /** Displays the given integer starting at the cursor location,
      *  and advances the cursor appropriately. */
     function void printInt(int i) {
+        var String s;
+        let s = String.new(6); // Max int is 5 chars + sign
+        do s.setInt(i);
+        do Output.printString(s);
+        do s.dispose();
+        return;
     }
 
     /** Advances the cursor to the beginning of the next line. */
     function void println() {
+        let cursorCol = 0;
+        let cursorRow = cursorRow + 1;
+         if (cursorRow > 22) {
+            let cursorRow = 0;
+        }
+        return;
     }
 
     /** Moves the cursor one column back. */
     function void backSpace() {
+        if (cursorCol > 0) {
+            let cursorCol = cursorCol - 1;
+        } else {
+            if (cursorRow > 0) {
+                let cursorRow = cursorRow - 1;
+                let cursorCol = 63;
+            }
+        }
+        return;
     }
 }