xK/xM/gen-icon.swift

100 lines
3.7 KiB
Swift

// gen-icon.swift: generate a program icon for xM in the Apple icon format
//
// Copyright (c) 2023, Přemysl Eric Janouch <p@janouch.name>
// SPDX-License-Identifier: 0BSD
//
// As an odd regression, AppKit may be necessary for JIT linking.
import AppKit
// NSGraphicsContext mostly just weirdly wraps over Quartz,
// so we do it all in Quartz directly.
import CoreGraphics
import Foundation
import ImageIO
import UniformTypeIdentifiers
// Apple uses something that's close to a "quintic superellipse" in their icons,
// but doesn't quite match. Either way, it looks better than rounded rectangles.
func addSquircle(context: CGContext, bounds: CGRect) {
context.move(to: CGPoint(x: bounds.maxX, y: bounds.midY))
for theta in stride(from: 0.0, to: .pi * 2, by: .pi / 1e4) {
let x = pow(abs(cos(theta)), 2 / 5.0) * bounds.width / 2
* CGFloat(signOf: cos(theta), magnitudeOf: 1) + bounds.midX
let y = pow(abs(sin(theta)), 2 / 5.0) * bounds.height / 2
* CGFloat(signOf: sin(theta), magnitudeOf: 1) + bounds.midY
context.addLine(to: CGPoint(x: x, y: y))
}
context.closePath()
}
func drawIcon(scale: CGFloat) -> CGImage? {
let size = CGSizeMake(1024, 1024)
let colorspace = CGColorSpaceCreateDeviceRGB()
let context = CGContext(data: nil,
width: Int(size.width * scale), height: Int(size.height * scale),
bitsPerComponent: 8, bytesPerRow: 0, space: colorspace,
bitmapInfo: CGImageAlphaInfo.premultipliedLast.rawValue)!
context.scaleBy(x: scale, y: scale)
let bounds = CGRectMake(100, 100, size.width - 200, size.height - 200)
addSquircle(context: context, bounds: bounds)
let squircle = context.path!
// Gradients don't draw shadows, so draw it separately.
context.saveGState()
context.setShadow(offset: CGSizeMake(0, -12).applying(context.ctm),
blur: 28 * scale, color: CGColor(gray: 0, alpha: 0.5))
context.setFillColor(CGColor(red: 1, green: 0x55p-8, blue: 0, alpha: 1))
context.fillPath()
context.restoreGState()
context.saveGState()
context.addPath(squircle)
context.clip()
context.drawLinearGradient(
CGGradient(colorsSpace: colorspace, colors: [
CGColor(red: 1, green: 0x00p-8, blue: 0, alpha: 1),
CGColor(red: 1, green: 0xaap-8, blue: 0, alpha: 1)
] as CFArray, locations: [0, 1])!,
start: CGPointMake(0, 100), end: CGPointMake(0, size.height - 100),
options: CGGradientDrawingOptions(rawValue: 0))
context.restoreGState()
context.move(to: CGPoint(x: size.width * 0.30, y: size.height * 0.30))
context.addLine(to: CGPoint(x: size.width * 0.30, y: size.height * 0.70))
context.addLine(to: CGPoint(x: size.width * 0.575, y: size.height * 0.425))
context.move(to: CGPoint(x: size.width * 0.70, y: size.height * 0.30))
context.addLine(to: CGPoint(x: size.width * 0.70, y: size.height * 0.70))
context.addLine(to: CGPoint(x: size.width * 0.425, y: size.height * 0.425))
context.setLineWidth(80)
context.setLineCap(.round)
context.setLineJoin(.round)
context.setStrokeColor(CGColor.white)
context.strokePath()
return context.makeImage()
}
if CommandLine.arguments.count != 2 {
print("Usage: \(CommandLine.arguments.first!) OUTPUT.icns")
exit(EXIT_FAILURE)
}
let filename = CommandLine.arguments[1]
let macOSSizes: Array<CGFloat> = [16, 32, 128, 256, 512]
let icns = CGImageDestinationCreateWithURL(
URL(fileURLWithPath: filename) as CFURL,
UTType.icns.identifier as CFString, macOSSizes.count * 2, nil)!
for size in macOSSizes {
CGImageDestinationAddImage(icns, drawIcon(scale: size / 1024.0)!, nil)
CGImageDestinationAddImage(icns, drawIcon(scale: size / 1024.0 * 2)!, [
kCGImagePropertyDPIWidth: 144,
kCGImagePropertyDPIHeight: 144,
] as CFDictionary)
}
if !CGImageDestinationFinalize(icns) {
print("ICNS finalization failed.")
exit(EXIT_FAILURE)
}