banjun

import Foundation
import RealityFoundation

///
/// ```swift
/// renderTextureScene.entities.append(rootEntity.clone(recursive: true))
/// let renderTextureMaterial = UnlitMaterial(texture: renderTextureScene.textureResources[0])
/// ModelEntity(mesh: .generatePlane(width: 1, height: 1), materials: [renderTextureMaterial])
/// ...
///

banjun

import SwiftUI
import Observation

// Leaks Malloc 48 Bytes block, 144 Bytes block, 128 Bytes block on macOS 15.3 (24D60), Xcode 16.2 (16C5032a)
// leaks speed is ~ +10MB / 5 mins, with Instruments

@main
struct SwiftUIObservationLeaksApp: App {
    @State private var model: Model = .init()
    @MainActor @Observable final class Model {

banjun

extension ModelEntity {
    /// create example model with skeleton: https://openusd.org/dev/api/_usd_skel__schema_overview.html
    static func createUsdSkelExample() async throws -> ModelEntity {
        var d = MeshDescriptor()
        d.positions = .init([
            .init(0.5, -0.5, 4), .init(-0.5, -0.5, 4), .init(0.5, 0.5, 4), .init(-0.5, 0.5, 4),
            .init(-0.5, -0.5, 0), .init(0.5, -0.5, 0), .init(-0.5, 0.5, 0), .init(0.5, 0.5, 0),
            .init(-0.5, 0.5, 2), .init(0.5, 0.5, 2), .init(0.5, -0.5, 2), .init(-0.5, -0.5, 2)])
        d.primitives = .trianglesAndQuads(triangles: [], quads: [
            2, 3, 1, 0,

banjun

import SwiftUI
import RealityKit

@main
struct KibouApp: App {
    @Environment(\.scenePhase) private var scenePhase
    @State private var transform: Transform = .identity
    @GestureState private var dragState: SIMD3<Float>?

    var body: some SwiftUI.Scene {

banjun

import Foundation

extension Timer {
    @MainActor @discardableResult static func scheduledTimerOnMainRunLoop(withTimeInterval: TimeInterval, repeats: Bool, block: @escaping @MainActor (Timer) -> Void) -> Timer {
        // The doc says: Creates and returns a new NSTimer object initialized with the specified block object and schedules it on the current run loop
        // But the block is not annotated with @MainActor and we need MainActor.assumeIsolated
        // Since Timer is non-Sendable, capture by nonisolated(unsafe) to pass from nonisolated context to MainActor.
        Timer.scheduledTimer(withTimeInterval: withTimeInterval, repeats: repeats) { timer in
            nonisolated(unsafe) let timer: Timer = timer
            MainActor.assumeIsolated {

banjun

import simd

func generatePlaneMesh(lengthInMeter: Float = 1, divisions: Int = 100, name: String = "GeneratedPlane") {
    let n = divisions
    let xys: [(Int, Int)] = (0..<n).flatMap { y in (0..<n).map { x in (x, y) }}
    let points: [SIMD3<Float>] = xys.map { x, y in
        SIMD3(Float(x) / Float(n - 1) - 0.5, Float(y) / Float(n - 1) - 0.5, 0) * lengthInMeter
    }
    let faceVertexIndices: [Int] = xys.flatMap { x, y in
        guard x < n - 1, y < n - 1 else { return [Int]() }

banjun

struct MultiColumnText: View {
    private let storage: NSTextStorage
    private let layoutManager: NSLayoutManager = .init()
    private let containers: [NSTextContainer]

    init(text: NSAttributedString, columns: Int) {
        storage = .init(attributedString: text)
        storage.addLayoutManager(layoutManager)
        containers = (0..<columns).map {_ in .init()}
        containers.forEach {

banjun

import RealityKit

extension ShapeResource {
    /// generate a box with its surfaces facing inward.
    /// NOTE: size 30 works with interactions, 50 does not work with interactions
    static func generateInwardBox(size: Float) async throws -> ShapeResource {
        // An array of vertex positions containing discrete points on the mesh.
        let meshPositions: [SIMD3<Float>] = [
            .init(-1, -1, -1), // 0 LBF
            .init(+1, -1, -1), // 1 RBF

banjun

import SwiftUI

// prerequisites in Info.plist: NSUserActivityTypes contains type, UIApplicationSceneManifest/UIApplicationSupportsMultipleScenes = YES
// accepts NSUserActivity.targetContentIdentifier = type
// see also: https://developer.apple.com/documentation/swiftui/scene/handlesexternalevents(matching:)
struct UserActivityWindowGroup<Content: View, Payload: Codable>: Scene {
    var type: String
    @ViewBuilder var content: (Payload) -> Content

    init(type: String, payloadType: Payload.Type, @ViewBuilder content: @escaping (Payload) -> Content) {

banjun

#!/bin/zsh

if [[ -z $BOGO_ARM64_TO_SIM ]]; then
    echo "❌ requires BOGO_ARM64_TO_SIM: set an executable binary path built from https://github.com/bogo/arm64-to-sim"
    exit 1;
fi

set -eu
# set -x # debug log