Source/BoardView.m
author snej@snej.local
Tue Mar 10 22:36:23 2009 -0700 (2009-03-10)
changeset 27 b0affce7beb1
parent 23 efe5d4523a23
permissions -rw-r--r--
Fixed some problems reported by the CLANG static analyzer.
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/*  This code is based on Apple's "GeekGameBoard" sample code, version 1.0.
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    http://developer.apple.com/samplecode/GeekGameBoard/
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    Copyright © 2007 Apple Inc. Copyright © 2008 Jens Alfke. All Rights Reserved.
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    Redistribution and use in source and binary forms, with or without modification, are permitted
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    provided that the following conditions are met:
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    * Redistributions of source code must retain the above copyright notice, this list of conditions
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      and the following disclaimer.
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    * Redistributions in binary form must reproduce the above copyright notice, this list of
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      conditions and the following disclaimer in the documentation and/or other materials provided
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      with the distribution.
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    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR
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    IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND 
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    FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRI-
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    BUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
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    (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 
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    PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
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    CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF 
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    THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*/
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#import "BoardView.h"
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#import "Bit.h"
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#import "BitHolder.h"
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#import "Game+Protected.h"
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#import "Turn.h"
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#import "Player.h"
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#import "QuartzUtils.h"
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#import "GGBUtils.h"
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#define kMaxPerspective 0.965   // 55 degrees
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@interface BoardView ()
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- (void) _findDropTarget: (NSPoint)pos;
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@end
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@implementation BoardView
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@synthesize table=_table, gameBoardInset=_gameBoardInset;
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- (void) dealloc
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{
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    [_game release];
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    [super dealloc];
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}
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#pragma mark -
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#pragma mark PERSPECTIVE:
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- (void) _applyPerspective
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{
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    CATransform3D t;
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    if( fabs(_perspective) >= M_PI/180 ) {
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        CGSize size = self.layer.bounds.size;
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        t = CATransform3DMakeTranslation(-size.width/2, -size.height/4, 0);
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        t = CATransform3DConcat(t, CATransform3DMakeRotation(-_perspective, 1,0,0));
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        CATransform3D pers = CATransform3DIdentity;
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        pers.m34 = 1.0/-2000;
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        t = CATransform3DConcat(t, pers);
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        t = CATransform3DConcat(t, CATransform3DMakeTranslation(size.width/2, 
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                                                                size.height*(0.25 + 0.05*sin(2*_perspective)),
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                                                                0));
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        self.layer.borderWidth = 3;
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    } else {
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        t = CATransform3DIdentity;
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        self.layer.borderWidth = 0;
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    }
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    self.layer.transform = t;
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}    
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- (CGFloat) perspective {return _perspective;}
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- (void) setPerspective: (CGFloat)p
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{
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    p = MAX(0.0, MIN(kMaxPerspective, p));
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    if( p != _perspective ) {
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        _perspective = p;
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        [self _applyPerspective];
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        _game.tablePerspectiveAngle = p;
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    }
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}
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- (IBAction) tiltUp: (id)sender     {self.perspective -= M_PI/40;}
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- (IBAction) tiltDown: (id)sender   {self.perspective += M_PI/40;}
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#pragma mark -
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#pragma mark GAME BOARD:
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- (void) _removeGameBoard
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{
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    if( _table ) {
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        RemoveImmediately(_table);
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        _table = nil;
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    }
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}
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- (void) createGameBoard
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{
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    [self _removeGameBoard];
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    _table = [[CALayer alloc] init];
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    _table.frame = [self gameBoardFrame];
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    _table.autoresizingMask = kCALayerMinXMargin | kCALayerMaxXMargin | kCALayerMinYMargin | kCALayerMaxYMargin;
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    // Tell the game to set up the board:
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    _game.tablePerspectiveAngle = _perspective;
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    _game.table = _table;
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    [self.layer addSublayer: _table];
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    [_table release];
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}
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- (Game*) game
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{
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    return _game;
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}
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- (void) setGame: (Game*)game
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{
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    if( game!=_game ) {
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        _game.table = nil;
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        setObj(&_game,game);
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        [self createGameBoard];
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    }
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}
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- (void) startGameNamed: (NSString*)gameClassName
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{
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    Class gameClass = NSClassFromString(gameClassName);
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    Game *game = [[gameClass alloc] init];
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    if( game ) {
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        self.game = game;
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        [game release];
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    }
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}
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#pragma mark -
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#pragma mark VIEW MANIPULATION:
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- (CGRect) gameBoardFrame
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{
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    return CGRectInset(self.layer.bounds, _gameBoardInset.width,_gameBoardInset.height);
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}
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- (void)resetCursorRects
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{
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    [super resetCursorRects];
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    if( _game.okToMove )
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        [self addCursorRect: self.bounds cursor: [NSCursor openHandCursor]];
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}
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- (NSView*) fullScreenView
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{
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    return _fullScreenView ?: self;
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}
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- (IBAction) enterFullScreen: (id)sender
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{
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    //[self _removeGameBoard];
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    if( self.fullScreenView.isInFullScreenMode ) {
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        [self.fullScreenView exitFullScreenModeWithOptions: nil];
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    } else {
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        [self.fullScreenView enterFullScreenMode: self.window.screen 
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                                     withOptions: nil];
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    }
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    //[self createGameBoard];
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}
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- (void)viewWillStartLiveResize
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{
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    [super viewWillStartLiveResize];
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    _oldSize = self.frame.size;
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}
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- (void)setFrameSize:(NSSize)newSize
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{
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    [super setFrameSize: newSize];
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    if( _oldSize.width > 0.0f ) {
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        CGAffineTransform xform = _table.affineTransform;
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        xform.a = xform.d = MIN(newSize.width,newSize.height)/MIN(_oldSize.width,_oldSize.height);
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        BeginDisableAnimations();
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        [self _applyPerspective];
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        _table.affineTransform = xform;
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        EndDisableAnimations();
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    } else
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        [self createGameBoard];
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}
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- (void)viewDidEndLiveResize
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{
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    [super viewDidEndLiveResize];
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    _oldSize.width = _oldSize.height = 0.0f;
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    [self createGameBoard];
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}
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#pragma mark -
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#pragma mark KEY EVENTS:
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- (BOOL) performKeyEquivalent: (NSEvent*)ev
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{
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    if( [ev.charactersIgnoringModifiers hasPrefix: @"\033"] ) {       // Esc key
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        if( self.fullScreenView.isInFullScreenMode ) {
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            [self performSelector: @selector(enterFullScreen:) withObject: nil afterDelay: 0.0];
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            // without the delayed-perform, NSWindow crashes right after this method returns!
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            return YES;
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        }
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    }
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    return NO;
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}
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#pragma mark -
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#pragma mark HIT-TESTING:
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/** Converts a point from window coords, to this view's root layer's coords. */
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- (CGPoint) _convertPointFromWindowToLayer: (NSPoint)locationInWindow
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{
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    NSPoint where = [self convertPoint: locationInWindow fromView: nil];    // convert to view coords
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    where = [self convertPointToBase: where];                               // then to layer base coords
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    return [self.layer convertPoint: NSPointToCGPoint(where)                // then to transformed layer coords
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                          fromLayer: self.layer.superlayer];
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}
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// Hit-testing callbacks (to identify which layers caller is interested in):
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typedef BOOL (*LayerMatchCallback)(CALayer*);
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static BOOL layerIsBit( CALayer* layer )        {return [layer isKindOfClass: [Bit class]];}
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static BOOL layerIsBitHolder( CALayer* layer )  {return [layer conformsToProtocol: @protocol(BitHolder)];}
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static BOOL layerIsDropTarget( CALayer* layer ) {return [layer respondsToSelector: @selector(draggingEntered:)];}
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/** Locates the layer at a given point in window coords.
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    If the leaf layer doesn't pass the layer-match callback, the nearest ancestor that does is returned.
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    If outOffset is provided, the point's position relative to the layer is stored into it. */
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- (CALayer*) hitTestPoint: (NSPoint)locationInWindow
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         forLayerMatching: (LayerMatchCallback)match
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                   offset: (CGPoint*)outOffset
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{
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    CGPoint where = [self _convertPointFromWindowToLayer: locationInWindow ];
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    CALayer *layer = [_table hitTest: where];
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    while( layer ) {
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        if( match(layer) ) {
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            CGPoint bitPos = [self.layer convertPoint: layer.position 
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                              fromLayer: layer.superlayer];
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            if( outOffset )
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                *outOffset = CGPointMake( bitPos.x-where.x, bitPos.y-where.y);
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            return layer;
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        } else
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            layer = layer.superlayer;
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    }
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    return nil;
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}
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#pragma mark -
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#pragma mark MOUSE CLICKS & DRAGS:
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- (void) mouseDown: (NSEvent*)ev
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{
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    if( ! _game.okToMove ) {
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        NSBeep();
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        return;
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    }
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    BOOL placing = NO;
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    _dragStartPos = ev.locationInWindow;
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    _dragBit = (Bit*) [self hitTestPoint: _dragStartPos
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                        forLayerMatching: layerIsBit 
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                                  offset: &_dragOffset];
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    if( ! _dragBit ) {
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        // If no bit was clicked, see if it's a BitHolder the game will let the user add a Bit to:
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        id<BitHolder> holder = (id<BitHolder>) [self hitTestPoint: _dragStartPos
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                                                 forLayerMatching: layerIsBitHolder
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                                                           offset: NULL];
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        if( holder ) {
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            _dragBit = [_game bitToPlaceInHolder: holder];
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            if( _dragBit ) {
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                _dragOffset.x = _dragOffset.y = 0;
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                if( _dragBit.superlayer==nil )
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                    _dragBit.position = [self _convertPointFromWindowToLayer: _dragStartPos];
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                placing = YES;
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            }
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        }
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    }
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    if( ! _dragBit ) {
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        Beep();
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        return;
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    }
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    // Clicked on a Bit:
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    _dragMoved = NO;
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    _dropTarget = nil;
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    _oldHolder = _dragBit.holder;
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    // Ask holder's and game's permission before dragging:
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    if( _oldHolder ) {
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        _dragBit = [_oldHolder canDragBit: _dragBit];
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        if( _dragBit && ! [_game canBit: _dragBit moveFrom: _oldHolder] ) {
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            [_oldHolder cancelDragBit: _dragBit];
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            _dragBit = nil;
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        }
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        if( ! _dragBit ) {
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            _oldHolder = nil;
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            NSBeep();
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            return;
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        }
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    }
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    // Start dragging:
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    _oldSuperlayer = _dragBit.superlayer;
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    _oldLayerIndex = [_oldSuperlayer.sublayers indexOfObjectIdenticalTo: _dragBit];
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    _oldPos = _dragBit.position;
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    ChangeSuperlayer(_dragBit, self.layer, self.layer.sublayers.count);
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    _dragBit.pickedUp = YES;
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    [[NSCursor closedHandCursor] push];
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    if( placing ) {
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        if( _oldSuperlayer )
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            _dragBit.position = [self _convertPointFromWindowToLayer: _dragStartPos];
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        _dragMoved = YES;
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        [self _findDropTarget: _dragStartPos];
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    }
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}
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- (void) mouseDragged: (NSEvent*)ev
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{
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    if( _dragBit ) {
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        // Get the mouse position, and see if we've moved 3 pixels since the mouseDown:
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        NSPoint pos = ev.locationInWindow;
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        if( fabs(pos.x-_dragStartPos.x)>=3 || fabs(pos.y-_dragStartPos.y)>=3 )
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            _dragMoved = YES;
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        // Move the _dragBit (without animation -- it's unnecessary and slows down responsiveness):
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        CGPoint where = [self _convertPointFromWindowToLayer: pos];
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        where.x += _dragOffset.x;
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        where.y += _dragOffset.y;
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        CGPoint newPos = [_dragBit.superlayer convertPoint: where fromLayer: self.layer];
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        [CATransaction flush];
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        [CATransaction begin];
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        [CATransaction setValue:(id)kCFBooleanTrue
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                         forKey:kCATransactionDisableActions];
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        _dragBit.position = newPos;
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        [CATransaction commit];
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        // Find what it's over:
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        [self _findDropTarget: pos];
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    }
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}
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- (void) _findDropTarget: (NSPoint)locationInWindow
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{
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    locationInWindow.x += _dragOffset.x;
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    locationInWindow.y += _dragOffset.y;
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    id<BitHolder> target = (id<BitHolder>) [self hitTestPoint: locationInWindow
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                                             forLayerMatching: layerIsBitHolder
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                                                       offset: NULL];
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    if( target == _oldHolder )
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        target = nil;
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    if( target != _dropTarget ) {
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        [_dropTarget willNotDropBit: _dragBit];
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        _dropTarget.highlighted = NO;
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        _dropTarget = nil;
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    }
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    if( target ) {
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        CGPoint targetPos = [(CALayer*)target convertPoint: _dragBit.position
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                                                 fromLayer: _dragBit.superlayer];
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        if( [target canDropBit: _dragBit atPoint: targetPos]
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           && [_game canBit: _dragBit moveFrom: _oldHolder to: target] ) {
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            _dropTarget = target;
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            _dropTarget.highlighted = YES;
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        }
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    }
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}
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- (void) mouseUp: (NSEvent*)ev
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{
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    if( _dragBit ) {
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        if( _dragMoved ) {
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            // Update the drag tracking to the final mouse position:
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            [self mouseDragged: ev];
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            _dropTarget.highlighted = NO;
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   409
            _dragBit.pickedUp = NO;
jens@0
   410
jens@0
   411
            // Is the move legal?
jens@0
   412
            if( _dropTarget && [_dropTarget dropBit: _dragBit
jens@0
   413
                                            atPoint: [(CALayer*)_dropTarget convertPoint: _dragBit.position 
jens@0
   414
                                                                            fromLayer: _dragBit.superlayer]] ) {
jens@0
   415
                // Yes, notify the interested parties:
jens@0
   416
                [_oldHolder draggedBit: _dragBit to: _dropTarget];
jens@0
   417
                [_game bit: _dragBit movedFrom: _oldHolder to: _dropTarget];
jens@0
   418
            } else {
jens@0
   419
                // Nope, cancel:
jens@0
   420
                [_dropTarget willNotDropBit: _dragBit];
jens@3
   421
                if( _oldSuperlayer ) {
jens@3
   422
                    ChangeSuperlayer(_dragBit, _oldSuperlayer, _oldLayerIndex);
jens@3
   423
                    _dragBit.position = _oldPos;
jens@3
   424
                    [_oldHolder cancelDragBit: _dragBit];
jens@3
   425
                } else {
jens@3
   426
                    [_dragBit removeFromSuperlayer];
jens@3
   427
                }
jens@0
   428
            }
jens@0
   429
        } else {
jens@0
   430
            // Just a click, without a drag:
jens@0
   431
            _dropTarget.highlighted = NO;
jens@0
   432
            _dragBit.pickedUp = NO;
jens@0
   433
            ChangeSuperlayer(_dragBit, _oldSuperlayer, _oldLayerIndex);
jens@0
   434
            [_oldHolder cancelDragBit: _dragBit];
jens@0
   435
            if( ! [_game clickedBit: _dragBit] )
jens@0
   436
                NSBeep();
jens@0
   437
        }
jens@9
   438
jens@0
   439
        _dropTarget = nil;
jens@0
   440
        _dragBit = nil;
jens@0
   441
        [NSCursor pop];
jens@0
   442
    }
jens@0
   443
}
jens@0
   444
jens@0
   445
jens@22
   446
- (void)scrollWheel:(NSEvent *)e
jens@22
   447
{
jens@22
   448
    self.perspective += e.deltaY * M_PI/180;
jens@22
   449
    //Log(@"Perspective = %2.0f degrees (%5.3f radians)", self.perspective*180/M_PI, self.perspective);
jens@22
   450
}
jens@22
   451
jens@22
   452
jens@0
   453
#pragma mark -
jens@0
   454
#pragma mark INCOMING DRAGS:
jens@0
   455
jens@0
   456
jens@0
   457
// subroutine to call the target
jens@0
   458
static int tell( id target, SEL selector, id arg, int defaultValue )
jens@0
   459
{
jens@0
   460
    if( target && [target respondsToSelector: selector] )
jens@0
   461
        return (ssize_t) [target performSelector: selector withObject: arg];
jens@0
   462
    else
jens@0
   463
        return defaultValue;
jens@0
   464
}
jens@0
   465
jens@0
   466
jens@0
   467
- (NSDragOperation)draggingEntered:(id <NSDraggingInfo>)sender
jens@0
   468
{
jens@0
   469
    _viewDropTarget = [self hitTestPoint: [sender draggingLocation]
jens@0
   470
                        forLayerMatching: layerIsDropTarget
jens@0
   471
                                  offset: NULL];
jens@0
   472
    _viewDropOp = _viewDropTarget ?[_viewDropTarget draggingEntered: sender] :NSDragOperationNone;
jens@0
   473
    return _viewDropOp;
jens@0
   474
}
jens@0
   475
jens@0
   476
- (NSDragOperation)draggingUpdated:(id <NSDraggingInfo>)sender
jens@0
   477
{
jens@0
   478
    CALayer *target = [self hitTestPoint: [sender draggingLocation]
jens@0
   479
                        forLayerMatching: layerIsDropTarget 
jens@0
   480
                                  offset: NULL];
jens@0
   481
    if( target == _viewDropTarget ) {
jens@0
   482
        if( _viewDropTarget )
jens@0
   483
            _viewDropOp = tell(_viewDropTarget,@selector(draggingUpdated:),sender,_viewDropOp);
jens@0
   484
    } else {
jens@0
   485
        tell(_viewDropTarget,@selector(draggingExited:),sender,0);
jens@0
   486
        _viewDropTarget = target;
jens@0
   487
        if( _viewDropTarget )
jens@0
   488
            _viewDropOp = [_viewDropTarget draggingEntered: sender];
jens@0
   489
        else
jens@0
   490
            _viewDropOp = NSDragOperationNone;
jens@0
   491
    }
jens@0
   492
    return _viewDropOp;
jens@0
   493
}
jens@0
   494
jens@0
   495
- (BOOL)wantsPeriodicDraggingUpdates
jens@0
   496
{
jens@0
   497
    return (_viewDropTarget!=nil);
jens@0
   498
}
jens@0
   499
jens@0
   500
- (void)draggingExited:(id <NSDraggingInfo>)sender
jens@0
   501
{
jens@0
   502
    tell(_viewDropTarget,@selector(draggingExited:),sender,0);
jens@0
   503
    _viewDropTarget = nil;
jens@0
   504
}
jens@0
   505
jens@0
   506
- (BOOL)prepareForDragOperation:(id <NSDraggingInfo>)sender
jens@0
   507
{
jens@0
   508
    return tell(_viewDropTarget,@selector(prepareForDragOperation:),sender,YES);
jens@0
   509
}
jens@0
   510
jens@0
   511
- (BOOL)performDragOperation:(id <NSDraggingInfo>)sender
jens@0
   512
{
jens@0
   513
    return [_viewDropTarget performDragOperation: sender];
jens@0
   514
}
jens@0
   515
jens@0
   516
- (void)concludeDragOperation:(id <NSDraggingInfo>)sender
jens@0
   517
{
jens@0
   518
    tell(_viewDropTarget,@selector(concludeDragOperation:),sender,0);
jens@0
   519
}
jens@0
   520
jens@0
   521
- (void)draggingEnded:(id <NSDraggingInfo>)sender
jens@0
   522
{
jens@0
   523
    tell(_viewDropTarget,@selector(draggingEnded:),sender,0);
jens@0
   524
}
jens@0
   525
jens@0
   526
@end