added "Hold" functionality; revamped scoring system; added popup banner for 2+ lines removed at once; fixed bug at end game where shapes still present were not cleared away

Privyet/Assets.xcassets/panelback.imageset/Contents.json

@@ -0,0 +1,22 @@
+{
+  "images" : [
+    {
+      "filename" : "panelback.png",
+      "idiom" : "universal",
+      "scale" : "1x"
+    },
+    {
+      "filename" : "panelback@2x.png",
+      "idiom" : "universal",
+      "scale" : "2x"
+    },
+    {
+      "idiom" : "universal",
+      "scale" : "3x"
+    }
+  ],
+  "info" : {
+    "author" : "xcode",
+    "version" : 1
+  }
+}

Privyet/Base.lproj/Main.storyboard

@@ -15,54 +15,58 @@
                         <rect key="frame" x="0.0" y="0.0" width="414" height="896"/>
                         <autoresizingMask key="autoresizingMask" widthSizable="YES" heightSizable="YES"/>
                         <subviews>
-                            <view contentMode="scaleToFill" fixedFrame="YES" translatesAutoresizingMaskIntoConstraints="NO" id="rZI-CB-OQn">
-                                <rect key="frame" x="310" y="315" width="84" height="100"/>
-                                <autoresizingMask key="autoresizingMask" flexibleMinX="YES" flexibleMinY="YES" flexibleMaxY="YES"/>
-                                <subviews>
-                                    <imageView clipsSubviews="YES" userInteractionEnabled="NO" contentMode="scaleAspectFit" horizontalHuggingPriority="251" verticalHuggingPriority="251" fixedFrame="YES" image="whitebg" translatesAutoresizingMaskIntoConstraints="NO" id="2kD-q4-jVs">
-                                        <rect key="frame" x="0.0" y="0.0" width="84" height="100"/>
-                                        <autoresizingMask key="autoresizingMask" flexibleMaxX="YES" flexibleMaxY="YES"/>
-                                    </imageView>
-                                    <label opaque="NO" userInteractionEnabled="NO" contentMode="left" horizontalHuggingPriority="251" verticalHuggingPriority="251" text="SCORE" textAlignment="center" lineBreakMode="tailTruncation" baselineAdjustment="alignBaselines" adjustsFontSizeToFit="NO" id="InR-1s-zXh">
-                                        <rect key="frame" x="7" y="20" width="70" height="21"/>
-                                        <autoresizingMask key="autoresizingMask" widthSizable="YES" flexibleMinY="YES" flexibleMaxY="YES"/>
-                                        <fontDescription key="fontDescription" name="Avenir-Black" family="Avenir" pointSize="15"/>
-                                        <color key="textColor" red="0.13333333333333333" green="0.6470588235294118" blue="0.82745098039215681" alpha="1" colorSpace="calibratedRGB"/>
-                                        <nil key="highlightedColor"/>
-                                    </label>
-                                    <label opaque="NO" userInteractionEnabled="NO" contentMode="left" horizontalHuggingPriority="251" verticalHuggingPriority="251" text="999" textAlignment="center" lineBreakMode="tailTruncation" baselineAdjustment="alignBaselines" adjustsFontSizeToFit="NO" id="Zja-c9-zBQ">
-                                        <rect key="frame" x="0.0" y="45" width="84" height="39"/>
-                                        <autoresizingMask key="autoresizingMask" widthSizable="YES" flexibleMinY="YES" flexibleMaxY="YES"/>
-                                        <fontDescription key="fontDescription" name="Avenir-Light" family="Avenir" pointSize="35"/>
-                                        <color key="textColor" red="0.1333333333" green="0.64705882349999999" blue="0.82745098039999998" alpha="1" colorSpace="calibratedRGB"/>
-                                        <nil key="highlightedColor"/>
-                                    </label>
-                                </subviews>
-                            </view>
                             <view contentMode="scaleToFill" fixedFrame="YES" translatesAutoresizingMaskIntoConstraints="NO" id="5g3-e3-yLO">
-                                <rect key="frame" x="310" y="482" width="84" height="100"/>
+                                <rect key="frame" x="310" y="538" width="84" height="100"/>
                                 <autoresizingMask key="autoresizingMask" flexibleMinX="YES" flexibleMinY="YES" flexibleMaxY="YES"/>
                                 <subviews>
-                                    <imageView clipsSubviews="YES" userInteractionEnabled="NO" contentMode="scaleAspectFit" horizontalHuggingPriority="251" verticalHuggingPriority="251" fixedFrame="YES" image="whitebg" translatesAutoresizingMaskIntoConstraints="NO" id="nRI-Ry-bjG">
+                                    <imageView clipsSubviews="YES" userInteractionEnabled="NO" contentMode="scaleAspectFit" horizontalHuggingPriority="251" verticalHuggingPriority="251" fixedFrame="YES" image="panelback" translatesAutoresizingMaskIntoConstraints="NO" id="nRI-Ry-bjG">
                                         <rect key="frame" x="0.0" y="0.0" width="84" height="100"/>
                                         <autoresizingMask key="autoresizingMask" flexibleMaxX="YES" flexibleMaxY="YES"/>
                                     </imageView>
                                     <label opaque="NO" userInteractionEnabled="NO" contentMode="left" horizontalHuggingPriority="251" verticalHuggingPriority="251" text="LEVEL" textAlignment="center" lineBreakMode="tailTruncation" baselineAdjustment="alignBaselines" adjustsFontSizeToFit="NO" id="Boc-bL-hFe">
-                                        <rect key="frame" x="7" y="20" width="70" height="21"/>
+                                        <rect key="frame" x="7" y="51" width="70" height="21"/>
                                         <autoresizingMask key="autoresizingMask" widthSizable="YES" flexibleMinY="YES" flexibleMaxY="YES"/>
                                         <fontDescription key="fontDescription" name="Avenir-Black" family="Avenir" pointSize="15"/>
-                                        <color key="textColor" red="0.54509803921568623" green="0.45490196078431372" blue="0.76078431372549016" alpha="1" colorSpace="calibratedRGB"/>
+                                        <color key="textColor" red="1" green="1" blue="0.0" alpha="1" colorSpace="calibratedRGB"/>
                                         <nil key="highlightedColor"/>
                                     </label>
                                     <label opaque="NO" userInteractionEnabled="NO" contentMode="left" horizontalHuggingPriority="251" verticalHuggingPriority="251" text="999" textAlignment="center" lineBreakMode="tailTruncation" baselineAdjustment="alignBaselines" adjustsFontSizeToFit="NO" id="G8x-d8-J4Q">
-                                        <rect key="frame" x="0.0" y="45" width="84" height="39"/>
+                                        <rect key="frame" x="0.0" y="70" width="84" height="22"/>
                                         <autoresizingMask key="autoresizingMask" widthSizable="YES" flexibleMinY="YES" flexibleMaxY="YES"/>
-                                        <fontDescription key="fontDescription" name="Avenir-Light" family="Avenir" pointSize="35"/>
-                                        <color key="textColor" red="0.54509803921568623" green="0.45490196078431372" blue="0.76078431372549016" alpha="1" colorSpace="calibratedRGB"/>
+                                        <fontDescription key="fontDescription" name="Avenir-Black" family="Avenir" pointSize="20"/>
+                                        <color key="textColor" red="1" green="1" blue="0.0" alpha="1" colorSpace="calibratedRGB"/>
+                                        <nil key="highlightedColor"/>
+                                    </label>
+                                    <label opaque="NO" userInteractionEnabled="NO" contentMode="left" horizontalHuggingPriority="251" verticalHuggingPriority="251" text="SCORE" textAlignment="center" lineBreakMode="tailTruncation" baselineAdjustment="alignBaselines" adjustsFontSizeToFit="NO" id="InR-1s-zXh">
+                                        <rect key="frame" x="7" y="4" width="70" height="21"/>
+                                        <autoresizingMask key="autoresizingMask" widthSizable="YES" flexibleMinY="YES" flexibleMaxY="YES"/>
+                                        <fontDescription key="fontDescription" name="Avenir-Black" family="Avenir" pointSize="15"/>
+                                        <color key="textColor" white="1" alpha="1" colorSpace="custom" customColorSpace="genericGamma22GrayColorSpace"/>
+                                        <nil key="highlightedColor"/>
+                                    </label>
+                                    <label opaque="NO" userInteractionEnabled="NO" contentMode="left" horizontalHuggingPriority="251" verticalHuggingPriority="251" text="999" textAlignment="center" lineBreakMode="tailTruncation" baselineAdjustment="alignBaselines" adjustsFontSizeToFit="NO" id="Zja-c9-zBQ">
+                                        <rect key="frame" x="0.0" y="14" width="84" height="39"/>
+                                        <autoresizingMask key="autoresizingMask" widthSizable="YES" flexibleMinY="YES" flexibleMaxY="YES"/>
+                                        <fontDescription key="fontDescription" name="Avenir-Black" family="Avenir" pointSize="20"/>
+                                        <color key="textColor" white="1" alpha="1" colorSpace="custom" customColorSpace="genericGamma22GrayColorSpace"/>
                                         <nil key="highlightedColor"/>
                                     </label>
                                 </subviews>
                             </view>
+                            <label opaque="NO" userInteractionEnabled="NO" contentMode="left" horizontalHuggingPriority="251" verticalHuggingPriority="251" fixedFrame="YES" text="NEXT" textAlignment="natural" lineBreakMode="tailTruncation" baselineAdjustment="alignBaselines" adjustsFontSizeToFit="NO" translatesAutoresizingMaskIntoConstraints="NO" id="kjl-Kl-IpX">
+                                <rect key="frame" x="257" y="44" width="40" height="21"/>
+                                <autoresizingMask key="autoresizingMask" flexibleMaxX="YES" flexibleMaxY="YES"/>
+                                <fontDescription key="fontDescription" name="Avenir-Heavy" family="Avenir" pointSize="15"/>
+                                <color key="textColor" white="1" alpha="1" colorSpace="custom" customColorSpace="genericGamma22GrayColorSpace"/>
+                                <nil key="highlightedColor"/>
+                            </label>
+                            <label opaque="NO" userInteractionEnabled="NO" contentMode="left" horizontalHuggingPriority="251" verticalHuggingPriority="251" text="HOLD" textAlignment="natural" lineBreakMode="tailTruncation" baselineAdjustment="alignBaselines" adjustsFontSizeToFit="NO" id="BOe-2c-WvE">
+                                <rect key="frame" x="257" y="204" width="50" height="21"/>
+                                <autoresizingMask key="autoresizingMask" flexibleMaxX="YES" flexibleMaxY="YES"/>
+                                <fontDescription key="fontDescription" name="Avenir-Heavy" family="Avenir" pointSize="15"/>
+                                <color key="textColor" white="1" alpha="1" colorSpace="custom" customColorSpace="genericGamma22GrayColorSpace"/>
+                                <nil key="highlightedColor"/>
+                            </label>
                         </subviews>
                         <color key="backgroundColor" systemColor="systemPurpleColor" red="0.68627450980000004" green="0.32156862749999998" blue="0.87058823529999996" alpha="1" colorSpace="custom" customColorSpace="sRGB"/>
                         <gestureRecognizers/>
@@ -99,10 +103,10 @@
                     </connections>
                 </swipeGestureRecognizer>
             </objects>
-            <point key="canvasLocation" x="-64" y="86"/>
+            <point key="canvasLocation" x="-65.217391304347828" y="85.714285714285708"/>
         </scene>
     </scenes>
     <resources>
-        <image name="whitebg" width="84" height="100"/>
+        <image name="panelback" width="84" height="100"/>
     </resources>
 </document>

Privyet/Block.swift

@@ -37,6 +37,45 @@ enum BlockColor: Int, CustomStringConvertible, CaseIterable {
     }
 }
 
+// Rectangles in block coordinates
+class BlockRect {
+    var left: Int
+    var top: Int
+    var right: Int
+    var bottom: Int
+    
+    init(left: Int, top: Int, right: Int, bottom: Int) {
+        self.left = left
+        self.top = top
+        self.right = right
+        self.bottom = bottom
+    }
+    
+    convenience init(x: Int, y: Int) {
+        self.init(left: x, top: y, right: x, bottom: y)
+    }
+    
+    var width: Int {
+        return right - left + 1
+    }
+    
+    var height: Int {
+        return bottom - top + 1
+    }
+    
+    static func +(lhs: BlockRect, rhs: BlockRect) -> BlockRect {
+        return BlockRect(left: min(lhs.left, rhs.left), top: min(lhs.top, rhs.top), right: max(lhs.right, rhs.right), bottom: max(lhs.bottom, rhs.bottom))
+    }
+    
+    static func +=(lhs: BlockRect, rhs: BlockRect) -> BlockRect {
+        lhs.left = min(lhs.left, rhs.left)
+        lhs.top = min(lhs.top, rhs.top)
+        lhs.right = max(lhs.right, rhs.right)
+        lhs.bottom = max(lhs.bottom, rhs.bottom)
+        return lhs
+    }
+}
+
 // Represents a single block in the game.
 class Block: Hashable, CustomStringConvertible {
     // Constants

Privyet/GameScene.swift

@@ -22,6 +22,9 @@ class GameScene: SKScene {
     var tickLengthMillis = TickLengthLevelOne
     var lastTick: NSDate?
     
+    var scaleFactor: CGFloat!
+    var holdControlRect: CGRect!
+    
     var textureCache = Dictionary<String, SKTexture>()
     var textureAtlas: SKTextureAtlas?
     
@@ -41,7 +44,7 @@ class GameScene: SKScene {
         //print("Background is sized \(background.size)")
         
         // Scale computations
-        let scaleFactor = min(size.width / background.size.width, size.height / background.size.height)
+        scaleFactor = CGFloat(min(size.width / background.size.width, size.height / background.size.height))
         
         background.position = CGPoint(x: 0, y: 0)
         background.anchorPoint = CGPoint(x: 0, y: 1.0)
@@ -60,6 +63,14 @@ class GameScene: SKScene {
         shapeLayer.addChild(gameBoard)
         gameLayer.addChild(shapeLayer)
         
+        // Calculate area of "hold" piece for hit-testing
+        let holdBBox = Shape.boundingBox(baseColumn: HoldColumn, baseRow: HoldRow)
+        let holdWidth = CGFloat(holdBBox.width) * BlockSize
+        let holdHeight = CGFloat(holdBBox.height) * BlockSize
+        let holdX = LayerPosition.x + (CGFloat(HoldColumn) * BlockSize)
+        let holdY = LayerPosition.y + (CGFloat(HoldRow) * BlockSize)
+        holdControlRect = CGRect(x: holdX * scaleFactor, y: holdY * scaleFactor, width: holdWidth * scaleFactor, height: holdHeight * scaleFactor)
+        
         // Set the theme music to play infinitely.
         run(SKAction.repeatForever(SKAction.playSoundFileNamed("Sounds/theme.mp3", waitForCompletion: true)))
     }
@@ -98,6 +109,12 @@ class GameScene: SKScene {
         return CGPoint(x: x, y: y)
     }
     
+    func rectForBucket() -> CGRect {
+        let width = CGFloat(NumColumns) * BlockSize
+        let height = CGFloat(NumRows) * BlockSize
+        return CGRect(x: (LayerPosition.x + (BlockSize / 2)) * scaleFactor, y: (LayerPosition.y + (BlockSize / 2)) * scaleFactor, width: width * scaleFactor, height: height * scaleFactor)
+    }
+    
     // Add the "preview" shape to the current scene.  This also "rezzes in" a shape's block sprites.
     func addPreviewShapeToScene(shape: Shape, completion: @escaping () -> ()) {
         for block in shape.blocks {
@@ -155,9 +172,19 @@ class GameScene: SKScene {
     }
     
     // Animate the removed lines "exploding" and the remaining blocks dropping into place.
-    func animateCollapsingLines(linesToRemove: Array<Array<Block>>, fallenBlocks: Array<Array<Block>>, completion: @escaping () -> ()) {
+    func animateCollapsingLines(linesToRemove: Array<Array<Block>>, fallenBlocks: Array<Array<Block>>, fadingShapes: Array<Shape>, completion: @escaping () -> ()) {
         var longestDuration: TimeInterval = 0
         
+        // Animate the shapes fading out
+        for fadeShape in fadingShapes {
+            for block in fadeShape.blocks {
+                let sprite = block.sprite!
+                let fadeOutAction: SKAction = SKAction.fadeOut(withDuration: TimeInterval(0.1))
+                fadeOutAction.timingMode = .easeIn
+                sprite.run(SKAction.sequence([fadeOutAction, SKAction.removeFromParent()]))
+            }
+        }
+        
         // Animate the falling blocks dropping into place
         for (columnIdx, column) in fallenBlocks.enumerated() {
             for (blockIdx, block) in column.enumerated() {
@@ -204,4 +231,28 @@ class GameScene: SKScene {
         }
         run(SKAction.sequence([SKAction.wait(forDuration: longestDuration), SKAction.run(completion)]))
     }
+    
+    // Animate the multiple-line clearance banner.
+    func animateClearanceBanner(bannerName: String?) {
+        guard let name = bannerName else {
+            return
+        }
+        var texture = textureCache[name]
+        if texture == nil {
+            texture = textureAtlas?.textureNamed(name)
+            textureCache[name] = texture
+        }
+        let sprite = SKSpriteNode(texture: texture)
+        
+        sprite.position = CGPoint(x: LayerPosition.x + (CGFloat(NumColumns / 2) * BlockSize), y: LayerPosition.y - (CGFloat(NumRows / 2) * BlockSize))
+        sprite.zPosition = 20
+        sprite.alpha = 0
+        shapeLayer.addChild(sprite)
+        
+        // Animate a quick fade-in followed by a slow fade out
+        let fadeInAction: SKAction = SKAction.fadeAlpha(to: 0.9, duration: 0.05)
+        let fadeOutAction: SKAction = SKAction.fadeOut(withDuration: 1.5)
+        fadeOutAction.timingMode = .easeIn
+        sprite.run(SKAction.sequence([fadeInAction, fadeOutAction, SKAction.removeFromParent()]))
+    }
 }

Privyet/GameViewController.swift

@@ -10,9 +10,12 @@ import UIKit
 import SpriteKit
 import GameplayKit
 
+let ClearanceAnimation = [nil, "double", "triple", "privyet"]
+
 class GameViewController: UIViewController, PrivyetDelegate, UIGestureRecognizerDelegate {
     var scene: GameScene!
     var privyet: Privyet!
+    var bucketRect: CGRect!
     var panPointReference: CGPoint?
 
     @IBOutlet weak var scoreLabel: UILabel!
@@ -29,6 +32,10 @@ class GameViewController: UIViewController, PrivyetDelegate, UIGestureRecognizer
         scene = GameScene(size: skView.bounds.size)
         scene.scaleMode = .aspectFill
         
+        bucketRect = scene.rectForBucket()
+        //print("Computed bucket rectangle = \(bucketRect!)")
+        //print("Computed hold rectangle = \(scene.holdControlRect!)")
+        
         scene.tick = didTick
         
         privyet = Privyet()
@@ -45,7 +52,12 @@ class GameViewController: UIViewController, PrivyetDelegate, UIGestureRecognizer
     
     // Called when the user taps the screen
     @IBAction func didTap(_ sender: UITapGestureRecognizer) {
-        privyet.rotateShape()
+        let tapLoc = sender.location(in: view)
+        if bucketRect.contains(tapLoc) {
+            privyet.rotateShape()
+        } else if scene.holdControlRect.contains(tapLoc) {
+            privyet.holdShape()
+        }
     }
     
     // Called when the user slides their finger across the screen
@@ -129,7 +141,7 @@ class GameViewController: UIViewController, PrivyetDelegate, UIGestureRecognizer
         view.isUserInteractionEnabled = false
         scene.stopTicking()
         scene.playSound(sound: "Sounds/gameover.mp3")
-        scene.animateCollapsingLines(linesToRemove: privyet.removeAllBlocks(), fallenBlocks: privyet.removeAllBlocks()) {
+        scene.animateCollapsingLines(linesToRemove: privyet.removeAllBlocks(), fallenBlocks: privyet.removeAllBlocks(), fadingShapes: privyet.removeAllShapes()) {
             privyet.beginGame()
         }
     }
@@ -154,20 +166,52 @@ class GameViewController: UIViewController, PrivyetDelegate, UIGestureRecognizer
         scene.playSound(sound: "Sounds/drop.mp3")
     }
     
+    // Called when the current shape is put "on hold"
+    func gameShapePutOnHold(privyet: Privyet, firstHold: Bool) {
+        guard let held = privyet.heldShape else {
+            return
+        }
+        scene.stopTicking()
+        view.isUserInteractionEnabled = false
+        scene.redrawShape(shape: held) {
+            if (firstHold) {
+                self.nextShape() // act like the previous shape settled
+            } else {
+                self.scene.redrawShape(shape: privyet.fallingShape!) {
+                    self.scene.startTicking()
+                    self.view.isUserInteractionEnabled = true
+                }
+            }
+        }
+        scene.playSound(sound: "Sounds/zap.mp3")
+    }
+    
+    // Internal: called when a shape lands, used to keep from showing the "special" banner more than once
+    func internalDidLand(privyet: Privyet, showBanner: Bool) {
+        let removedLines = privyet.removeCompletedLines()
+        let linesCount = removedLines.linesRemoved.count
+        if linesCount > 0 {
+            self.scoreLabel.text = "\(privyet.score)"
+            if (showBanner) {
+                scene.animateClearanceBanner(bannerName: ClearanceAnimation[linesCount - 1])
+            }
+            scene.animateCollapsingLines(linesToRemove: removedLines.linesRemoved, fallenBlocks: removedLines.fallenBlocks, fadingShapes: []) {
+                self.internalDidLand(privyet: privyet, showBanner: (linesCount <= 1) && showBanner)
+            }
+            self.scene.playSound(sound: "Sounds/bomb.mp3")
+            if showBanner && linesCount == 4 {
+                self.scene.playSound(sound: "Sounds/privyet.mp3")
+            }
+        } else {
+            nextShape()
+        }
+    }
+    
     // Called when a shape "lands" on top of existing blocks or at the bottom of the bucket
     func gameShapeDidLand(privyet: Privyet) {
         scene.stopTicking()
         self.view.isUserInteractionEnabled = false
-        let removedLines = privyet.removeCompletedLines()
-        if removedLines.linesRemoved.count > 0 {
-            self.scoreLabel.text = "\(privyet.score)"
-            scene.animateCollapsingLines(linesToRemove: removedLines.linesRemoved, fallenBlocks: removedLines.fallenBlocks) {
-                self.gameShapeDidLand(privyet: privyet)
-            }
-            self.scene.playSound(sound: "Sounds/bomb.mp3")
-        } else {
-            nextShape()
-        }
+        internalDidLand(privyet: privyet, showBanner: true)
     }
     
     // Called when a shape moves on the screen

Privyet/Privyet.swift

@@ -15,10 +15,14 @@ let StartingColumn = 4
 let StartingRow = 0
 
 let PreviewColumn = 12
-let PreviewRow = 1
+let PreviewRow = 3
 
-let PointsPerLine = 10
-let LevelThreshold = 500
+let HoldColumn = 12
+let HoldRow = 10
+
+// number of points for single (1 line), double (2 lines), triple (3 lines), Privyet (4 lines)
+let PointsPerLine = [1, 2, 5, 10]
+let LevelThreshold = 50
 
 protocol PrivyetDelegate {
     // Invoked when the current round of Privyet ends
@@ -36,6 +40,9 @@ protocol PrivyetDelegate {
     // invoked when the falling shape has changed its location after being dropped
     func gameShapeDidDrop(privyet: Privyet)
     
+    // invoked when the current shape is put on hold
+    func gameShapePutOnHold(privyet: Privyet, firstHold: Bool)
+    
     // invoked when the game has reached a new level
     func gameDidLevelUp(privyet: Privyet)
 }
@@ -44,6 +51,7 @@ class Privyet {
     var bucket: Array2D<Block>
     var nextShape: Shape?
     var fallingShape: Shape?
+    var heldShape: Shape?
     var delegate: PrivyetDelegate?
     
     var score = 0
@@ -52,6 +60,7 @@ class Privyet {
     init() {
         fallingShape = nil
         nextShape = nil
+        heldShape = nil
         bucket = Array2D<Block>(columns: NumColumns, rows: NumRows)
     }
     
@@ -154,7 +163,7 @@ class Privyet {
         }
         
         // Advance score and game level as appropriate
-        let pointsEarned = removedLines.count * PointsPerLine * level
+        let pointsEarned = PointsPerLine[removedLines.count - 1] * max(level / 2, 1)
         score += pointsEarned
         if score >= level * LevelThreshold {
             level += 1
@@ -201,6 +210,21 @@ class Privyet {
         return allBlocks
     }
     
+    // Removes all stored shapes from their slots (at end of game). Returns all the removed shapes.
+    func removeAllShapes() -> Array<Shape> {
+        var allShapes = Array<Shape>()
+        for shape in [fallingShape, nextShape, heldShape] {
+            guard let s = shape else {
+                continue
+            }
+            allShapes.append(s)
+        }
+        fallingShape = nil
+        nextShape = nil
+        heldShape = nil
+        return allShapes
+    }
+    
     // Drop the falling shape down as far as it will go.
     func dropShape() {
         guard let shape = fallingShape else {
@@ -272,4 +296,22 @@ class Privyet {
         }
         delegate?.gameShapeDidMove(privyet: self)
     }
+    
+    // Places current shape "on hold."
+    func holdShape() {
+        guard let shape = fallingShape else {
+            return
+        }
+        guard let held = heldShape else {
+            shape.moveTo(column: HoldColumn, row: HoldRow)
+            heldShape = shape
+            fallingShape = nil
+            delegate?.gameShapePutOnHold(privyet: self, firstHold: true)
+            return
+        }
+        shape.exchangePositions(other: held)
+        fallingShape = held
+        heldShape = shape
+        delegate?.gameShapePutOnHold(privyet: self, firstHold: false)
+    }
 }

Privyet/Shape.swift

@@ -131,6 +131,21 @@ class Shape: Hashable, CustomStringConvertible {
         }
     }
     
+    final func getBoundingBoxForOrientation(baseColumn: Int, baseRow: Int, orientation: Orientation) -> BlockRect {
+        guard let offsets = blockRowColumnPositions[orientation] else {
+            return BlockRect(x: baseColumn, y: baseRow)
+        }
+        
+        let blockRects = offsets.map { (offset) -> BlockRect in
+            return BlockRect(x: baseColumn + offset.columnDiff, y: baseRow + offset.rowDiff)
+        }
+        return blockRects[0] + blockRects[1] + blockRects[2] + blockRects[3]
+    }
+    
+    final func getBoundingBox(baseColumn: Int, baseRow: Int) -> BlockRect {
+        return getBoundingBoxForOrientation(baseColumn: baseColumn, baseRow: baseRow, orientation: .Zero) + getBoundingBoxForOrientation(baseColumn: baseColumn, baseRow: baseRow, orientation: .Ninety) + getBoundingBoxForOrientation(baseColumn: baseColumn, baseRow: baseRow, orientation: .OneEighty) + getBoundingBoxForOrientation(baseColumn: baseColumn, baseRow: baseRow, orientation: .TwoSeventy)
+    }
+    
     // Rotate the blocks in this shape to a new orientation.
     final func rotateBlocks(orientation: Orientation) {
         guard let blockRowColumnTranslation: Array<(columnDiff: Int, rowDiff: Int)> = blockRowColumnPositions[orientation] else {
@@ -193,6 +208,17 @@ class Shape: Hashable, CustomStringConvertible {
         rotateBlocks(orientation: orientation)
     }
     
+    final func exchangePositions(other: Shape) {
+        var tmp = other.column
+        other.column = self.column
+        self.column = tmp
+        tmp = other.row
+        other.row = self.row
+        self.row = tmp
+        other.rotateBlocks(orientation: other.orientation)
+        rotateBlocks(orientation: orientation)
+    }
+    
     // Generates a random shape.
     final class func random(startingColumn: Int, startingRow: Int) -> Shape {
         switch Int.random(in: 0 ..< NumShapeTypes) {
@@ -212,4 +238,14 @@ class Shape: Hashable, CustomStringConvertible {
             return ZShape(column: startingColumn, row: startingRow)
         }
     }
+    
+    final class func boundingBox(baseColumn: Int, baseRow: Int) -> BlockRect {
+        return SquareShape(column: 0, row: 0).getBoundingBox(baseColumn: baseColumn, baseRow: baseRow) +
+            TShape(column: 0, row: 0).getBoundingBox(baseColumn: baseColumn, baseRow: baseRow) +
+            LineShape(column: 0, row: 0).getBoundingBox(baseColumn: baseColumn, baseRow: baseRow) +
+            LShape(column: 0, row: 0).getBoundingBox(baseColumn: baseColumn, baseRow: baseRow) +
+            JShape(column: 0, row: 0).getBoundingBox(baseColumn: baseColumn, baseRow: baseRow) +
+            SShape(column: 0, row: 0).getBoundingBox(baseColumn: baseColumn, baseRow: baseRow) +
+            ZShape(column: 0, row: 0).getBoundingBox(baseColumn: baseColumn, baseRow: baseRow)
+    }
 }