diff -r 000000000000 -r e9f7ba4718e1 Source/Grid.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Source/Grid.h	Fri Mar 07 11:43:02 2008 -0800
@@ -0,0 +1,139 @@
+/*  This code is based on Apple's "GeekGameBoard" sample code, version 1.0.
+    http://developer.apple.com/samplecode/GeekGameBoard/
+    Copyright © 2007 Apple Inc. Copyright © 2008 Jens Alfke. All Rights Reserved.
+
+    Redistribution and use in source and binary forms, with or without modification, are permitted
+    provided that the following conditions are met:
+
+    * Redistributions of source code must retain the above copyright notice, this list of conditions
+      and the following disclaimer.
+    * Redistributions in binary form must reproduce the above copyright notice, this list of
+      conditions and the following disclaimer in the documentation and/or other materials provided
+      with the distribution.
+
+    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR
+    IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND 
+    FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRI-
+    BUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+    (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 
+    PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+    CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF 
+    THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+#import "BitHolder.h"
+@class GridCell;
+
+
+/** Abstract superclass of regular geometric grids of GridCells that Bits can be placed on. */
+@interface Grid : CALayer
+{
+    unsigned _nRows, _nColumns;                         
+    CGSize _spacing;                                    
+    Class _cellClass;                                   
+    CGColorRef _cellColor, _lineColor;                  
+    BOOL _usesDiagonals, _allowsMoves, _allowsCaptures;
+    NSMutableArray *_cells;                             // Really a 2D array, in row-major order.
+}
+
+/** Initializes a new Grid with the given dimensions and cell size, and position in superview.
+    Note that a new Grid has no cells! Either call -addAllCells, or -addCellAtRow:column:. */
+- (id) initWithRows: (unsigned)nRows columns: (unsigned)nColumns
+            spacing: (CGSize)spacing
+           position: (CGPoint)pos;
+
+/** Initializes a new Grid with the given dimensions and frame in superview.
+    The cell size will be computed by dividing frame size by dimensions.
+    Note that a new Grid has no cells! Either call -addAllCells, or -addCellAtRow:column:. */
+- (id) initWithRows: (unsigned)nRows columns: (unsigned)nColumns
+              frame: (CGRect)frame;
+
+@property Class cellClass;                      // What kind of GridCells to create
+@property (readonly) unsigned rows, columns;    // Dimensions of the grid
+@property (readonly) CGSize spacing;            // x,y spacing of GridCells
+@property CGColorRef cellColor, lineColor;      // Cell background color, line color (or nil)
+@property BOOL usesDiagonals;                   // Affects GridCell.neighbors, for rect grids
+@property BOOL allowsMoves, allowsCaptures;     // Can pieces be moved, and can they land on others?
+
+/** Returns the GridCell at the given coordinates, or nil if there is no cell there.
+    It's OK to call this with off-the-board coordinates; it will just return nil.*/
+- (GridCell*) cellAtRow: (unsigned)row column: (unsigned)col;
+
+/** Adds cells at all coordinates, creating a complete grid. */
+- (void) addAllCells;
+
+/** Adds a GridCell at the given coordinates. */
+- (GridCell*) addCellAtRow: (unsigned)row column: (unsigned)col;
+
+/** Removes a particular cell, leaving a blank space. */
+- (void) removeCellAtRow: (unsigned)row column: (unsigned)col;
+
+
+// protected:
+- (GridCell*) createCellAtRow: (unsigned)row column: (unsigned)col 
+               suggestedFrame: (CGRect)frame;
+
+@end
+
+
+/** Abstract superclass of a single cell in a grid. */
+@interface GridCell : BitHolder
+{
+    Grid *_grid;
+    unsigned _row, _column;
+}
+
+- (id) initWithGrid: (Grid*)grid 
+                row: (unsigned)row column: (unsigned)col
+              frame: (CGRect)frame;
+
+@property (readonly) Grid* grid;
+@property (readonly) unsigned row, column;
+@property (readonly) NSArray* neighbors;        // Dependent on grid.usesDiagonals
+
+/** Returns YES if 'forward' is north (increasing row#) for the current player */
+@property (readonly) BOOL fwdIsN;
+
+/* Go-style group detection. Returns the set of contiguous GridCells that have pieces of the same
+   owner as this one, and optionally a count of the number of "liberties", or adjacent empty cells. */
+- (NSSet*) getGroup: (int*)outLiberties;
+
+// protected:
+- (void) drawInParentContext: (CGContextRef)ctx fill: (BOOL)fill;
+@end
+
+
+
+/** A rectangular grid of squares. */
+@interface RectGrid : Grid
+{
+    CGColorRef _altCellColor;
+}
+
+/** If non-nil, alternate cells will be drawn with this background color, in a checkerboard pattern.
+    The precise rule is that cells whose row+column is odd use the altCellColor.*/
+@property CGColorRef altCellColor;
+
+@end
+
+
+
+/* A square in a RectGrid */
+@interface Square : GridCell
+
+@property (readonly) Square *nw, *n, *ne, *e, *se, *s, *sw, *w;    // Absolute directions (n = increasing row#)
+@property (readonly) Square *fl, *f, *fr, *r, *br, *b, *bl, *l;    // Relative to player (upside-down for player 2)
+
+@end
+
+
+/* Substitute this for Square in a RectGrid's cellClass to draw the lines through the centers
+   of the squares, so the pieces sit on the intersections, as in a Go board. */
+@interface GoSquare : Square
+{
+    BOOL _dotted;
+}
+
+/** Set to YES to put a dot at the intersection, as in the handicap points of a Go board. */
+@property BOOL dotted;
+
+@end