# CGRect ## 目前版本 {% tabs %} {% tab title="🌀 CGRect" %} ```swift /* * ⭐️ required: * - 🅿️ Rectangular */ import SwiftUI // for CGRect // 🌀CGRect + Rectangular extension CGRect: Rectangular { } // 🌀CGRect + convenience inits extension CGRect { /// CGRect(x,y,w,h) public init(_ x: CGFloat, _ y: CGFloat, _ width: CGFloat, _ height: CGFloat) { self.init(x: x, y: y, width: width, height: height) } /// rect from one corner to another. /// `CGRect(from: A, to: B)` public init(from p1: CGPoint, to p2: CGPoint) { let x = p1.x let y = p1.y let w = p2.x - p1.x let h = p2.y - p1.y self.init(x: x, y: y, width: w, height: h) } /// rect with center and corner. /// - `CGRect(center: A, corner: B)` public init(center: CGPoint, corner: CGPoint) { let x = corner.x let y = corner.y let dx = center.x - corner.x let dy = center.y - corner.y self.init(x: x, y: y, width: 2 * dx, height: 2 * dy) } /* ------ Modifiers -------- */ /// - turn a `CGRect` into `Path` public var path: Path { Path(self) } } ``` {% endtab %} {% tab title="💈 範例" %} ```swift import SwiftUI // ⭐️ required: 🌀CGPoint+Vector2D, 🌀CGRect // points let A = CGPoint(40, 40) let B = CGPoint(80, 70) // rects let rect1 = CGRect(from: A, to: B) // origin: (40,40), size:(30,40) let rect2 = CGRect(center: A, corner: B) // origin: ( 0,10), size:(60,80) // instance members rect1.point(0.5, 0.5) // (60, 55) rect2.point(1,1) // (80, 70) rect2.bottomRight // (80, 70) rect2.corners // [(0,70), (80,70), (80,10), (0,10)] // subscript let p = CGPoint(1,2) // 🌀CGPoint let size = CGSize(20, 20) // 🌀CGSize let rect = CGRect(origin: p, size: size / 2) // 🌀CGSize + 🅿️Vector2D rect[ 0, 0] // ( 1, 2) rect[ 1, 0] // ( 11, 2) rect[ 0, 1] // ( 1, 12) rect[ 2, 1] // ( 21, 12) rect[-2,-2] // (-19, -18) ``` {% endtab %} {% tab title="👨‍🦳 " %} * [🌀 Rectangular](/ios/custom/package/geometrykit/frame.md) {% endtab %} {% tab title="👶 " %} * [🌀 GeometryProxy](/ios/swiftui/view/measure/geometryproxy/geometryproxy.md) {% endtab %} {% tab title="👥 相關" %} * [🌀 GeometryProxy](/ios/swiftui/view/measure/geometryproxy/geometryproxy.md) * [📦 GeometryReader](/ios/swiftui/view/measure/geometryreader.md) * [Calling Types As Functions](/ios/features/callasfunction.md) {% endtab %} {% tab title="🍎 " %} * CoreGraphics ⟩ [CGRect](https://developer.apple.com/documentation/coregraphics/cgrect) * CoreGraphics ⟩ [CGPoint](https://developer.apple.com/documentation/coregraphics/cgpoint?language=occ) {% endtab %} {% tab title="✏️ 紀錄" %} * 2020.09.30：➕ added .**path** * 2020.10.08：\ ➕ .**maxSide** \ ✏️ ~~minLength~~ ➝ **minSide**\ ➕ **CGRect**(x, y, w, h)\ ➕ **subscript**: rect\[x, y] {% endtab %} {% endtabs %} ## 修改記錄 {% tabs %} {% tab title="✏️ 紀錄 " %} * 2020.09.30：➕ added .**path** * 2020.10.08：\ ➕ .**maxSide** \ ✏️ ~~minLength~~ ➝ **minSide**\ ➕ **CGRect**(x, y, w, h)\ ➕ **subscript**: rect\[x, y] * ➊ 2020.10.11：將大部分的功能移至 [Rectangular](/ios/custom/package/geometrykit/frame.md) {% endtab %} {% tab title="➊" %} ```swift // 封存日期：2020.10.11 // 修改內容： // 1. 將大部分的功能移至 Rectangular // 2. 移除對 Vector2D 的依賴 // ------------------------------------ /* * ⭐️ required: * - 🅿️ Vector2D */ import SwiftUI // for CGRect import VectorSpace // for 🅿️ Vector2D // 🌀CGRect extension CGRect { /* ------- ⭐️ Points ------- */ /// # Key Points of a CGRect /// - Example: `.top`, `.bottom`, `.center`, ... public enum KeyPoint: CaseIterable { case topLeft, top, topRight case left, center, right case bottomLeft, bottom, bottomRight } // `rect.point(at: .top) == rect.top` public func point(at position: KeyPoint) -> CGPoint { switch position { case .topLeft : return topLeft case .top : return top case .topRight : return topRight case .left : return left case .center : return center case .right : return right case .bottomLeft : return bottomLeft case .bottom : return bottom case .bottomRight: return bottomRight } } // rect.top, ... public var top : CGPoint { CGPoint(x: midX, y: minY) } public var bottom : CGPoint { CGPoint(x: midX, y: maxY) } public var left : CGPoint { CGPoint(x: minX, y: midY) } public var right : CGPoint { CGPoint(x: maxX, y: midY) } public var center : CGPoint { CGPoint(x: midX, y: midY) } public var bottomLeft : CGPoint { CGPoint(x: minX, y: maxY) } public var bottomRight: CGPoint { CGPoint(x: maxX, y: maxY) } public var topLeft : CGPoint { CGPoint(x: minX, y: minY) } public var topRight : CGPoint { CGPoint(x: maxX, y: minY) } /// 4 corners of a rect public var corners: [CGPoint] { [bottomLeft, bottomRight, topRight, topLeft] } /// # Relative Point /// a point relative to the rectangle's width and height /// ## Examples /// - `rect.point(0,0) == rect.topLeft` /// - `rect.point(1,1) == rect.bottomRight` public func point(_ x: CGFloat, _ y: CGFloat) -> CGPoint { let u = topRight - topLeft // 🅿️ Vector2D let v = bottomLeft - topLeft let w = x * u + y * v return topLeft + w } /// ## Examples /// - `rect[1,0] == rect.topRight` /// - `rect[0,1] == rect.bottomLeft` public subscript(_ x: CGFloat, _ y: CGFloat) -> CGPoint { point(x, y) } /* ------- ⭐️ Dimensions ------- */ /// side length of the rect. public var minSide: CGFloat { min(width, height) } public var maxSide: CGFloat { max(width, height) } /* ------- ⭐️ Initializers ------- */ /// CGRect(x,y,w,h) public init(_ x: CGFloat, _ y: CGFloat, _ width: CGFloat, _ height: CGFloat) { self.init(x: x, y: y, width: width, height: height) } /// draws a `CGRect` from a corner to another corner. /// `CGRect(from: A, to: B)` public init(from p1: CGPoint, to p2: CGPoint) { let x = min(p1.x, p2.x) let y = min(p1.y, p2.y) let w = abs(p1.x - p2.x) let h = abs(p1.y - p2.y) self.init(x: x, y: y, width: w, height: h) } /// draws a `CGRect` with center and a corner. /// - `CGRect(center: A, corner: B)` public init(center p1: CGPoint, corner p2: CGPoint) { self.init(from: p2, to: 2 * p1 - p2) // 🅿️ Vector2D } /* ------ Modifiers -------- */ /// - turn a `CGRect` into `Path` public var path: Path { Path(self) } } ``` {% endtab %} {% endtabs %} --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. 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