update at 2026-03-15 15:58:14

scripts/generate-kindle-clock-assets.swift

@@ -0,0 +1,166 @@
+#!/usr/bin/env swift
+
+import AppKit
+import Foundation
+
+struct HandConfig {
+  let sourcePath: String
+  let outputDirectoryName: String
+  let frameCount: Int
+  let sourceWidth: CGFloat
+  let sourceHeight: CGFloat
+  let pivotX: CGFloat
+  let pivotY: CGFloat
+  let digits: Int
+  let angleStep: CGFloat
+}
+
+enum AssetError: Error, CustomStringConvertible {
+  case invalidImage(String)
+  case pngEncodingFailed(String)
+
+  var description: String {
+    switch self {
+    case let .invalidImage(path):
+      return "无法读取图片：\(path)"
+    case let .pngEncodingFailed(path):
+      return "无法编码 PNG：\(path)"
+    }
+  }
+}
+
+let fileManager = FileManager.default
+let workingDirectory = URL(fileURLWithPath: fileManager.currentDirectoryPath, isDirectory: true)
+let repoRoot = CommandLine.arguments.count > 1
+  ? URL(fileURLWithPath: CommandLine.arguments[1], isDirectory: true)
+  : workingDirectory
+let outputRoot = CommandLine.arguments.count > 2
+  ? URL(fileURLWithPath: CommandLine.arguments[2], isDirectory: true)
+  : repoRoot.appendingPathComponent("assets/kindle-clock", isDirectory: true)
+
+let faceSourceURL = repoRoot.appendingPathComponent("assets/clock-face.png")
+let targetSize = NSSize(width: 220, height: 220)
+let faceSourceSize = NSSize(width: 431, height: 431)
+let scale = targetSize.width / faceSourceSize.width
+
+let handConfigs = [
+  HandConfig(
+    sourcePath: "assets/hour-hand.png",
+    outputDirectoryName: "hour-hand",
+    frameCount: 720,
+    sourceWidth: 32,
+    sourceHeight: 205,
+    pivotX: 13,
+    pivotY: 138,
+    digits: 3,
+    angleStep: 0.5
+  ),
+  HandConfig(
+    sourcePath: "assets/minite-hand.png",
+    outputDirectoryName: "minute-hand",
+    frameCount: 60,
+    sourceWidth: 32,
+    sourceHeight: 288,
+    pivotX: 15,
+    pivotY: 203,
+    digits: 2,
+    angleStep: 6
+  ),
+]
+
+func loadImage(at url: URL) throws -> NSImage {
+  guard let image = NSImage(contentsOf: url) else {
+    throw AssetError.invalidImage(url.path)
+  }
+
+  return image
+}
+
+func savePNG(_ image: NSImage, to url: URL) throws {
+  guard
+    let tiffRepresentation = image.tiffRepresentation,
+    let bitmap = NSBitmapImageRep(data: tiffRepresentation),
+    let pngData = bitmap.representation(using: .png, properties: [:])
+  else {
+    throw AssetError.pngEncodingFailed(url.path)
+  }
+
+  try fileManager.createDirectory(
+    at: url.deletingLastPathComponent(),
+    withIntermediateDirectories: true
+  )
+  try pngData.write(to: url)
+}
+
+func renderImage(size: NSSize, draw: () -> Void) -> NSImage {
+  let image = NSImage(size: size)
+  image.lockFocusFlipped(true)
+  NSColor.clear.setFill()
+  NSBezierPath(rect: NSRect(origin: .zero, size: size)).fill()
+  draw()
+  image.unlockFocus()
+  return image
+}
+
+func renderFace() throws {
+  let faceImage = try loadImage(at: faceSourceURL)
+  let renderedFace = renderImage(size: targetSize) {
+    faceImage.draw(
+      in: NSRect(origin: .zero, size: targetSize),
+      from: NSRect(origin: .zero, size: faceImage.size),
+      operation: .sourceOver,
+      fraction: 1
+    )
+  }
+
+  try savePNG(renderedFace, to: outputRoot.appendingPathComponent("clock-face.png"))
+}
+
+func renderHandFrames(config: HandConfig) throws {
+  let sourceURL = repoRoot.appendingPathComponent(config.sourcePath)
+  let handImage = try loadImage(at: sourceURL)
+  let outputDirectory = outputRoot.appendingPathComponent(config.outputDirectoryName, isDirectory: true)
+  let scaledWidth = config.sourceWidth * scale
+  let scaledHeight = config.sourceHeight * scale
+  let scaledPivotX = config.pivotX * scale
+  let scaledPivotY = config.pivotY * scale
+
+  try fileManager.createDirectory(at: outputDirectory, withIntermediateDirectories: true)
+
+  for frameIndex in 0..<config.frameCount {
+    let angle = CGFloat(frameIndex) * config.angleStep
+    let renderedFrame = renderImage(size: targetSize) {
+      guard let context = NSGraphicsContext.current?.cgContext else {
+        return
+      }
+
+      context.translateBy(x: targetSize.width / 2, y: targetSize.height / 2)
+      context.rotate(by: angle * .pi / 180)
+      context.translateBy(x: -scaledPivotX, y: -scaledPivotY)
+
+      handImage.draw(
+        in: NSRect(x: 0, y: 0, width: scaledWidth, height: scaledHeight),
+        from: NSRect(origin: .zero, size: handImage.size),
+        operation: .sourceOver,
+        fraction: 1
+      )
+    }
+
+    let filename = String(format: "%0\(config.digits)d.png", frameIndex)
+    try savePNG(renderedFrame, to: outputDirectory.appendingPathComponent(filename))
+  }
+}
+
+do {
+  try fileManager.createDirectory(at: outputRoot, withIntermediateDirectories: true)
+  try renderFace()
+
+  for config in handConfigs {
+    try renderHandFrames(config: config)
+  }
+
+  print("Generated Kindle clock assets at \(outputRoot.path)")
+} catch {
+  fputs("\(error)\n", stderr)
+  exit(1)
+}