Move sky/examples to sky/sdk/lib/example, and code changes to support that change. Fixes T277.

sky/examples/game/lib/node.dart

Index: sky/examples/game/lib/node.dart
diff --git a/sky/examples/game/lib/node.dart b/sky/examples/game/lib/node.dart
deleted file mode 100644
index cfb5eab2a571c3bacddcf7456401e186f3288779..0000000000000000000000000000000000000000
--- a/sky/examples/game/lib/node.dart
+++ /dev/null
@@ -1,530 +0,0 @@
-part of sprites;
-
-double convertDegrees2Radians(double degrees) => degrees * Math.PI/180.8;
-
-double convertRadians2Degrees(double radians) => radians * 180.0/Math.PI;
-
-/// A base class for all objects that can be added to the sprite node tree and rendered to screen using [SpriteBox] and
-/// [SpriteWidget].
-///
-/// The [Node] class itself doesn't render any content, but provides the basic functions of any type of node, such as
-/// handling transformations and user input. To render the node tree, a root node must be added to a [SpriteBox] or a
-/// [SpriteWidget]. Commonly used sub-classes of [Node] are [Sprite], [NodeWithSize], and many more upcoming subclasses.
-///
-/// Nodes form a hierarchical tree. Each node can have a number of children, and the transformation (positioning,
-/// rotation, and scaling) of a node also affects its children.
-class Node {
-
-  // Member variables
-
-  SpriteBox _spriteBox;
-  Node _parent;
-
-  Point _position = Point.origin;
-  double _rotation = 0.0;
-
-  Matrix4 _transformMatrix = new Matrix4.identity();
-  Matrix4 _transformMatrixNodeToBox;
-  Matrix4 _transformMatrixBoxToNode;
-
-  double _scaleX = 1.0;
-  double _scaleY = 1.0;
-
-  /// The visibility of this node and its children.
-  bool visible = true;
-
-  double _zPosition = 0.0;
-  int _addedOrder;
-  int _childrenLastAddedOrder = 0;
-  bool _childrenNeedSorting = false;
-
-  /// Decides if the node and its children is currently paused.
-  ///
-  /// A paused node will not receive any input events, update calls, or run any animations.
-  ///
-  ///     myNodeTree.paused = true;
-  bool paused = false;
-
-  bool _userInteractionEnabled = false;
-
-  /// If set to true the node will receive multiple pointers, otherwise it will only receive events the first pointer.
-  ///
-  /// This property is only meaningful if [userInteractionEnabled] is set to true. Default value is false.
-  ///
-  ///     class MyCustomNode extends Node {
-  ///       handleMultiplePointers = true;
-  ///     }
-  bool handleMultiplePointers = false;
-  int _handlingPointer;
-
-  List<Node>_children = [];
-
-  // Constructors
-
-  /// Creates a new [Node] without any transformation.
-  ///
-  ///     var myNode = new Node();
-  Node() {
-  }
-
-  // Property setters and getters
-
-  /// The [SpriteBox] this node is added to, or null if it's not currently added to a [SpriteBox].
-  ///
-  /// For most applications it's not necessary to access the [SpriteBox] directly.
-  ///
-  ///     // Get the transformMode of the sprite box
-  ///     var transformMode = myNode.spriteBox.transformMode;
-  SpriteBox get spriteBox => _spriteBox;
-
-  /// The parent of this node, or null if it doesn't have a parent.
-  ///
-  ///     // Hide the parent
-  ///     myNode.parent.visible = false;
-  Node get parent => _parent;
-
-  /// The rotation of this node in degrees.
-  ///
-  ///     myNode.rotation = 45.0;
-  double get rotation => _rotation;
-  
-  void set rotation(double rotation) {
-    assert(rotation != null);
-    _rotation = rotation;
-    _invalidateTransformMatrix();
-  }
-
-  /// The position of this node relative to its parent.
-  ///
-  ///     myNode.position = new Point(42.0, 42.0);
-  Point get position => _position;
-  
-  void set position(Point position) {
-    assert(position != null);
-    _position = position;
-    _invalidateTransformMatrix();
-  }
-
-  /// The draw order of this node compared to its parent and its siblings.
-  ///
-  /// By default nodes are drawn in the order that they have been added to a parent. To override this behavior the
-  /// [zPosition] property can be used. A higher value of this property will force the node to be drawn in front of
-  /// siblings that have a lower value. If a negative value is used the node will be drawn behind its parent.
-  ///
-  ///     nodeInFront.zPosition = 1.0;
-  ///     nodeBehind.zPosition = -1.0;
-  double get zPosition => _zPosition;
-
-  void set zPosition(double zPosition) {
-    assert(zPosition != null);
-    _zPosition = zPosition;
-    if (_parent != null) {
-      _parent._childrenNeedSorting = true;
-    }
-  }
-
-  /// The scale of this node relative its parent.
-  ///
-  /// The [scale] property is only valid if [scaleX] and [scaleY] are equal values.
-  ///
-  ///     myNode.scale = 5.0;
-  double get scale {
-    assert(_scaleX == _scaleY);
-    return _scaleX;
-  }
-
-  void set scale(double scale) {
-    assert(scale != null);
-    _scaleX = _scaleY = scale;
-    _invalidateTransformMatrix();
-  }
-
-  /// The horizontal scale of this node relative its parent.
-  ///
-  ///     myNode.scaleX = 5.0;
-  double get scaleX => _scaleX;
-
-  void set scaleX(double scaleX) {
-    assert(scaleX != null);
-    _scaleX = scaleX;
-    _invalidateTransformMatrix();
-  }
-
-  /// The vertical scale of this node relative its parent.
-  ///
-  ///     myNode.scaleY = 5.0;
-  double get scaleY => _scaleY;
-
-  void set scaleY(double scaleY) {
-    assert(scaleY != null);
-    _scaleY = scaleY;
-    _invalidateTransformMatrix();
-  }
-
-  /// A list of the children of this node.
-  ///
-  /// This list should only be modified by using the [addChild] and [removeChild] methods.
-  ///
-  ///     // Iterate over a nodes children
-  ///     for (Node child in myNode.children) {
-  ///       // Do something with the child
-  ///     }
-  List<Node> get children {
-    _sortChildren();
-    return _children;
-  }
-
-  // Adding and removing children
-
-  /// Adds a child to this node.
-  ///
-  /// The same node cannot be added to multiple nodes.
-  ///
-  ///     addChild(new Sprite(myImage));
-  void addChild(Node child) {
-    assert(child != null);
-    assert(child._parent == null);
-
-    _childrenNeedSorting = true;
-    _children.add(child);
-    child._parent = this;
-    child._spriteBox = this._spriteBox;
-    _childrenLastAddedOrder += 1;
-    child._addedOrder = _childrenLastAddedOrder;
-    if (_spriteBox != null) _spriteBox._eventTargets = null;
-  }
-
-  /// Removes a child from this node.
-  ///
-  ///     removeChild(myChildNode);
-  void removeChild(Node child) {
-    assert(child != null);
-    if (_children.remove(child)) {
-      child._parent = null;
-      child._spriteBox = null;
-      if (_spriteBox != null) _spriteBox._eventTargets = null;
-    }
-  }
-
-  /// Removes this node from its parent node.
-  ///
-  ///     removeFromParent();
-  void removeFromParent() {
-    assert(_parent != null);
-    _parent.removeChild(this);
-  }
-
-  /// Removes all children of this node.
-  ///
-  ///     removeAllChildren();
-  void removeAllChildren() {
-    for (Node child in _children) {
-      child._parent = null;
-      child._spriteBox = null;
-    }
-    _children = [];
-    _childrenNeedSorting = false;
-    if (_spriteBox != null) _spriteBox._eventTargets = null;
-  }
-
-  void _sortChildren() {
-    // Sort children primarily by zPosition, secondarily by added order
-    if (_childrenNeedSorting) {
-      _children.sort((Node a, Node b) {
-        if (a._zPosition == b._zPosition) {
-          return a._addedOrder - b._addedOrder;
-        }
-        else if (a._zPosition > b._zPosition) {
-          return 1;
-        }
-        else {
-          return -1;
-        }
-      });
-      _childrenNeedSorting = false;
-    }
-  }
-
-  // Calculating the transformation matrix
-
-  /// The transformMatrix describes the transformation from the node's parent.
-  ///
-  /// You cannot set the transformMatrix directly, instead use the position, rotation and scale properties.
-  ///
-  ///     Matrix4 matrix = myNode.transformMatrix;
-  Matrix4 get transformMatrix {
-    if (_transformMatrix != null) {
-      return _transformMatrix;
-    }
-    
-    double cx, sx, cy, sy;
-    
-    if (_rotation == 0.0) {
-      cx = 1.0;
-      sx = 0.0;
-      cy = 1.0;
-      sy = 0.0;
-    }
-    else {
-      double radiansX = convertDegrees2Radians(_rotation);
-      double radiansY = convertDegrees2Radians(_rotation);
-      
-      cx = Math.cos(radiansX);
-      sx = Math.sin(radiansX);
-      cy = Math.cos(radiansY);
-      sy = Math.sin(radiansY);
-    }
-
-    // Create transformation matrix for scale, position and rotation
-    _transformMatrix = new Matrix4(cy * _scaleX, sy * _scaleX, 0.0, 0.0,
-               -sx * _scaleY, cx * _scaleY, 0.0, 0.0,
-               0.0, 0.0, 1.0, 0.0,
-              _position.x, _position.y, 0.0, 1.0);
-    
-    return _transformMatrix;
-  }
-
-  void _invalidateTransformMatrix() {
-    _transformMatrix = null;
-    _invalidateToBoxTransformMatrix();
-  }
-
-  void _invalidateToBoxTransformMatrix () {
-    _transformMatrixNodeToBox = null;
-    _transformMatrixBoxToNode = null;
-
-    for (Node child in children) {
-      child._invalidateToBoxTransformMatrix();
-    }
-  }
-
-  // Transforms to other nodes
-
-  Matrix4 _nodeToBoxMatrix() {
-    assert(_spriteBox != null);
-    if (_transformMatrixNodeToBox != null) {
-      return _transformMatrixNodeToBox;
-    }
-
-    if (_parent == null) {
-      // Base case, we are at the top
-      assert(this == _spriteBox.rootNode);
-      _transformMatrixNodeToBox = new Matrix4.copy(_spriteBox.transformMatrix).multiply(transformMatrix);
-    }
-    else {
-      _transformMatrixNodeToBox = new Matrix4.copy(_parent._nodeToBoxMatrix()).multiply(transformMatrix);
-    }
-    return _transformMatrixNodeToBox;
-  }
-
-  Matrix4 _boxToNodeMatrix() {
-    assert(_spriteBox != null);
-
-    if (_transformMatrixBoxToNode != null) {
-      return _transformMatrixBoxToNode;
-    }
-
-    _transformMatrixBoxToNode = new Matrix4.copy(_nodeToBoxMatrix());
-    _transformMatrixBoxToNode.invert();
-
-    return _transformMatrixBoxToNode;
-  }
-
-  /// Converts a point from the coordinate system of the [SpriteBox] to the local coordinate system of the node.
-  ///
-  /// This method is particularly useful when handling pointer events and need the pointers position in a local
-  /// coordinate space.
-  ///
-  ///     Point localPoint = myNode.convertPointToNodeSpace(pointInBoxCoordinates);
-  Point convertPointToNodeSpace(Point boxPoint) {
-    assert(boxPoint != null);
-    assert(_spriteBox != null);
-
-    Vector4 v =_boxToNodeMatrix().transform(new Vector4(boxPoint.x, boxPoint.y, 0.0, 1.0));
-    return new Point(v[0], v[1]);
-  }
-
-  /// Converts a point from the local coordinate system of the node to the coordinate system of the [SpriteBox].
-  ///
-  ///     Point pointInBoxCoordinates = myNode.convertPointToBoxSpace(localPoint);
-  Point convertPointToBoxSpace(Point nodePoint) {
-    assert(nodePoint != null);
-    assert(_spriteBox != null);
-
-    Vector4 v =_nodeToBoxMatrix().transform(new Vector4(nodePoint.x, nodePoint.y, 0.0, 1.0));
-    return new Point(v[0], v[1]);
-  }
-
-  /// Converts a [point] from another [node]s coordinate system into the local coordinate system of this node.
-  ///
-  ///     Point pointInNodeASpace = nodeA.convertPointFromNode(pointInNodeBSpace, nodeB);
-  Point convertPointFromNode(Point point, Node node) {
-    assert(node != null);
-    assert(point != null);
-    assert(_spriteBox != null);
-    assert(_spriteBox == node._spriteBox);
-
-    Point boxPoint = node.convertPointToBoxSpace(point);
-    Point localPoint = convertPointToNodeSpace(boxPoint);
-
-    return localPoint;
-  }
-
-  // Hit test
-
-  /// Returns true if the [point] is inside the node, the [point] is in the local coordinate system of the node.
-  ///
-  ///     myNode.isPointInside(localPoint);
-  ///
-  /// [NodeWithSize] provides a basic bounding box check for this method, if you require a more detailed check this
-  /// method can be overridden.
-  ///
-  ///     bool isPointInside (Point nodePoint) {
-  ///       double minX = -size.width * pivot.x;
-  ///       double minY = -size.height * pivot.y;
-  ///       double maxX = minX + size.width;
-  ///       double maxY = minY + size.height;
-  ///       return (nodePoint.x >= minX && nodePoint.x < maxX &&
-  ///       nodePoint.y >= minY && nodePoint.y < maxY);
-  ///     }
-  bool isPointInside(Point point) {
-    assert(point != null);
-
-    return false;
-  }
-
-  // Rendering
-  
-  void _visit(RenderCanvas canvas) {
-    assert(canvas != null);
-    if (!visible) return;
-
-    _prePaint(canvas);
-    _visitChildren(canvas);
-    _postPaint(canvas);
-  }
-  
-  void _prePaint(RenderCanvas canvas) {
-    canvas.save();
-
-    // Get the transformation matrix and apply transform
-    canvas.concat(transformMatrix.storage);
-  }
-
-  /// Paints this node to the canvas.
-  ///
-  /// Subclasses, such as [Sprite], override this method to do the actual painting of the node. To do custom
-  /// drawing override this method and make calls to the [canvas] object. All drawing is done in the node's local
-  /// coordinate system, relative to the node's position. If you want to make the drawing relative to the node's
-  /// bounding box's origin, override [NodeWithSize] and call the applyTransformForPivot method before making calls for
-  /// drawing.
-  ///
-  ///     void paint(RenderCanvas canvas) {
-  ///       canvas.save();
-  ///       applyTransformForPivot(canvas);
-  ///
-  ///       // Do painting here
-  ///
-  ///       canvas.restore();
-  ///     }
-  void paint(RenderCanvas canvas) {
-  }
- 
-  void _visitChildren(RenderCanvas canvas) {
-    // Sort children if needed
-    _sortChildren();
-
-    int i = 0;
-
-    // Visit children behind this node
-    while (i < _children.length) {
-      Node child = _children[i];
-      if (child.zPosition >= 0.0) break;
-      child._visit(canvas);
-      i++;
-    }
-
-    // Paint this node
-    paint(canvas);
-
-    // Visit children in front of this node
-    while (i < _children.length) {
-      Node child = _children[i];
-      child._visit(canvas);
-      i++;
-    }
-  }
-  
-  void _postPaint(RenderCanvas canvas) {
-    canvas.restore();
-  }
-
-  // Receiving update calls
-
-  /// Called before a frame is drawn.
-  ///
-  /// Override this method to do any updates to the node or node tree before it's drawn to screen.
-  ///
-  ///     // Make the node rotate at a fixed speed
-  ///     void update(double dt) {
-  ///       rotation = rotation * 10.0 * dt;
-  ///     }
-  void update(double dt) {
-  }
-
-  /// Called whenever the [SpriteBox] is modified or resized, or if the device is rotated.
-  ///
-  /// Override this method to do any updates that may be necessary to correctly display the node or node tree with the
-  /// new layout of the [SpriteBox].
-  ///
-  ///     void spriteBoxPerformedLayout() {
-  ///       // Move some stuff around here
-  ///     }
-  void spriteBoxPerformedLayout() {
-  }
-
-  // Handling user interaction
-
-  /// The node will receive user interactions, such as pointer (touch or mouse) events.
-  ///
-  ///     class MyCustomNode extends NodeWithSize {
-  ///       userInteractionEnabled = true;
-  ///     }
-  bool get userInteractionEnabled => _userInteractionEnabled;
-
-  void set userInteractionEnabled(bool userInteractionEnabled) {
-    _userInteractionEnabled = userInteractionEnabled;
-    if (_spriteBox != null) _spriteBox._eventTargets = null;
-  }
-
-  /// Handles an event, such as a pointer (touch or mouse) event.
-  ///
-  /// Override this method to handle events. The node will only receive events if the [userInteractionEnabled] property
-  /// is set to true and the [isPointInside] method returns true for the position of the pointer down event (default
-  /// behavior provided by [NodeWithSize]). Unless [handleMultiplePointers] is set to true, the node will only receive
-  /// events for the first pointer that is down.
-  ///
-  /// Return true if the node has consumed the event, if an event is consumed it will not be passed on to nodes behind
-  /// the current node.
-  ///
-  ///     // MyTouchySprite gets transparent when we touch it
-  ///     class MyTouchySprite extends Sprite {
-  ///
-  ///       MyTouchySprite(Image img) : super (img) {
-  ///         userInteractionEnabled = true;
-  ///       }
-  ///
-  ///       bool handleEvent(SpriteBoxEvent event) {
-  ///         if (event.type == 'pointerdown) {
-  ///           opacity = 0.5;
-  ///         }
-  ///         else if (event.type == 'pointerup') {
-  ///           opacity = 1.0;
-  ///         }
-  ///         return true;
-  ///       }
-  ///     }
-  bool handleEvent(SpriteBoxEvent event) {
-    return false;
-  }
-}