2 files changed, 160 insertions, 1 deletions

diff --git a/src/ch/epfl/xblast/Cell.java b/src/ch/epfl/xblast/Cell.java
index 813bd5f..ef5ff60 100644
--- a/src/ch/epfl/xblast/Cell.java
+++ b/src/ch/epfl/xblast/Cell.java
@@ -102,7 +102,7 @@ public final class Cell {
      * @param n   the number to normalize (the dividend)
      * @return the normalized value
      */
-    private static int normalize(int max, int n) {
+    protected static int normalize(int max, int n) {
         return Math.floorMod(n, max);
     }
 
diff --git a/src/ch/epfl/xblast/SubCell.java b/src/ch/epfl/xblast/SubCell.java
new file mode 100644
index 0000000..2731029
--- /dev/null
+++ b/src/ch/epfl/xblast/SubCell.java
@@ -0,0 +1,159 @@
+package ch.epfl.xblast;
+
+/**
+ * A SubCell.
+ *
+ * @author Pacien TRAN-GIRARD (261948)
+ */
+public final class SubCell {
+
+    /**
+     * The number of x-subdivisions of each Cell.
+     */
+    public static final int SUB_COL_DIVISIONS = 16;
+
+    /**
+     * The number of y-subdivisions of each Cell.
+     */
+    public static final int SUB_ROW_DIVISIONS = 16;
+
+    /**
+     * The width of the board (total of sub-columns).
+     */
+    public static final int SUB_COLUMNS = SUB_COL_DIVISIONS * Cell.COLUMNS;
+
+    /**
+     * The height of the board (total of sub-rows).
+     */
+    public static final int SUB_ROWS = SUB_ROW_DIVISIONS * Cell.ROWS;
+
+    /**
+     * Returns the central SubCell of the given Cell.
+     *
+     * @param cell the reference Cell
+     * @return the central SubCell
+     */
+    public static SubCell centralSubCellOf(Cell cell) {
+        return new SubCell(
+                cell.x() * SUB_COL_DIVISIONS + (SUB_COL_DIVISIONS / 2),
+                cell.y() * SUB_ROW_DIVISIONS + (SUB_ROW_DIVISIONS / 2)
+        );
+    }
+
+    /**
+     * The coordinates of the SubCell.
+     */
+    private int x, y;
+
+    /**
+     * Instantiates a new SubCell with the given coordinates.
+     *
+     * @param x the x-coordinate
+     * @param y the y-coordinate
+     */
+    public SubCell(int x, int y) {
+        this.x = Cell.normalize(SUB_COLUMNS, x);
+        this.y = Cell.normalize(SUB_ROWS, y);
+    }
+
+    /**
+     * Returns the normalized x-coordinate of the SubCell.
+     *
+     * @return the x-coordinate
+     */
+    public int x() {
+        return this.x;
+    }
+
+    /**
+     * Returns the normalized y-coordinate of the SubCell.
+     *
+     * @return the y-coordinate
+     */
+    public int y() {
+        return this.y;
+    }
+
+    /**
+     * Computes the Manhattan distance to the given SubCell.
+     *
+     * @param subCell the other SubCell
+     * @return the distance
+     */
+    private int distanceTo(SubCell subCell) {
+        return Math.abs(this.x - subCell.x) + Math.abs(this.y - subCell.y);
+    }
+
+    /**
+     * Returns the Manhattan distance to the closest central SubCell.
+     *
+     * @return the distance
+     */
+    public int distanceToCentral() {
+        return this.distanceTo(centralSubCellOf(this.containingCell()));
+    }
+
+    /**
+     * Returns T(this SubCell is central).
+     *
+     * @return T(this SubCell is central)
+     */
+    public boolean isCentral() {
+        return this.distanceToCentral() == 0;
+    }
+
+    /**
+     * Returns the neighboring SubCell at the given Direction.
+     *
+     * @param dir the Direction
+     * @return the neighboring SubCell
+     */
+    public SubCell neighbor(Direction dir) {
+        switch (dir) {
+            case N:
+                return new SubCell(this.x, this.y - 1);
+            case S:
+                return new SubCell(this.x, this.y + 1);
+            case E:
+                return new SubCell(this.x + 1, this.y);
+            case W:
+                return new SubCell(this.x - 1, this.y);
+            default:
+                return null;
+        }
+    }
+
+    /**
+     * Returns the Cell containing this SubCell.
+     *
+     * @return the containing Cell
+     */
+    public Cell containingCell() {
+        return new Cell(this.x / SUB_COL_DIVISIONS, this.y / SUB_ROW_DIVISIONS);
+    }
+
+    /**
+     * Returns T(the given Object is equal to this SubCell (have the same coordinates)).
+     *
+     * @param that the Object to compare against
+     * @return T(the given Object is equal to this SubCell)
+     */
+    @Override
+    public boolean equals(Object that) {
+        if (that == null) return false;
+        if (that == this) return true;
+        if (!(that instanceof SubCell)) return false;
+        return (((SubCell) that).x == this.x && ((SubCell) that).y == this.y);
+    }
+
+    /**
+     * Returns a String representation of the coordinates of the SubCell.
+     *
+     * @return a String representation of the coordinates of the SubCell.
+     */
+    @Override
+    public String toString() {
+        return String.format("(%d,%d)", this.x, this.y);
+    }
+
+}