ForEach (0..< doesn't start at 0 - arrays

Question

I've the following code:
VStack (spacing: 0) {
ForEach (0..<myMaze.height, id: \.self) { (y: Int) in
HStack (spacing: 0) {
ForEach (0..<myMaze.width, id: \.self) { (x: Int) in
DrawRoom(xPos: x, yPos: y)
} // ForEach x
} // HSTack
} // ForEach y
} // VSTack
and
struct DrawRoom: View {
#ObservedObject var myMaze = Maze.sharedInstance
var xPos: Int
var yPos: Int
var body: some View {
Square(value: myMaze.value)
.stroke(Color.gray, style: StrokeStyle(lineWidth: 3))
.frame(width: myMaze.sideLength, height: myMaze.sideLength)
}
init(xPos: Int, yPos: Int) {
self.xPos = xPos
self.yPos = yPos
myMaze.value = myMaze.mazeData[xPos][yPos]
print("DrawRoom: [\(xPos), \(yPos)]")
}
}
... with the following output in the console:
X, Y
DrawRoom: [0, 2]
DrawRoom: [1, 2]
DrawRoom: [2, 2]
DrawRoom: [0, 0]
DrawRoom: [1, 0]
DrawRoom: [2, 0]
DrawRoom: [0, 1]
DrawRoom: [1, 1]
DrawRoom: [2, 1]
Surprisingly the "Y" starts at 2 then 0 and finally 1 but it should be as follows:
X, Y
DrawRoom: [0, 0]
DrawRoom: [1, 0]
DrawRoom: [2, 0]
DrawRoom: [0, 1]
DrawRoom: [1, 1]
DrawRoom: [2, 1]
DrawRoom: [0, 2]
DrawRoom: [1, 2]
DrawRoom: [2, 2]
Can somebody explain me why, is there something wrong in my coding?
For info, "Square" draws lines according to the value of myMaze.mazeData[xPos][yPos]
See below the whole code:
//
// Maze.swift
// NewMaze
//
// Created by Philippe Lagarrigue on 26/12/2020.
//
import Foundation
import SwiftUI
let side = ["North", "East", "South", "West"]
let direction = [1, 2, 4, 8]
let wall = (North: 1, East: 2, South: 4, West: 8) // 15 means all walls
let exit = (toNorth: 16, toEast: 32, toSouth: 64, toWest: 128) // 0 means no exit
struct Room {
var x: Int
var y: Int
var roomsToExit: Int
}
class Maze: ObservableObject {
// Properties
static let sharedInstance = Maze()
var viewWidth = CGFloat(0.0) //{ didSet { update(flag: 2) } }
var viewHeight = CGFloat(0.0) //{ didSet { update(flag: 2) } }
var ready2Draw = false
var width = 0 // Number of rooms (horizontally)
var height = 0 // Number of rooms (vertically)
#Published var widthDouble = CGFloat(3.0) { didSet { ready2Draw = false } }
#Published var heightDouble = CGFloat(3.0) { didSet { ready2Draw = false } }
var oneWay = true
var exitRoom = Room(x: 0, y: 0, roomsToExit: 0)
var farestRoom = Room(x: 0, y: 0, roomsToExit: 0)
var currentPos = Room(x: 0, y: 0, roomsToExit: 0)
var mazeData = [[Int]]()
//var width: Int { return Int(widthDouble) } // Number of rooms (horizontally)
//var height: Int { return Int(heightDouble) } // Number of rooms (vertically)
var numberOfRooms: Int { return self.width * self.height }
var sideLength = CGFloat(40.0) //{ didSet { print("sideLength: \(sideLength)") } }
var value = 15 // { didSet { print("value: \(value)") } }
func defineExit() {
let choosenSide = Int.random(in: 0...3) // N, E, S or W
// Fill array with 15 which means that all walls are set
mazeData = Array(repeating: Array(repeating: 15, count: self.height), count: self.width)
//var count = 0
//for x in 0..<width {
// for y in 0..<height {
// print(x, y, count, count/height, count%height)
// mazeData[x][y] = 15
// count += 1
// }
//}
print("\nchoosenSide: \(side[choosenSide]) (\(choosenSide))")
if (choosenSide + 1) % 2 == 0 {
print("Axe: E-W")
exitRoom.x = choosenSide == 3 ? 0 : self.width - 1
exitRoom.y = Int.random(in: 1..<self.height)
} else {
print("Axe: N-S")
exitRoom.x = Int.random(in: 1..<self.width)
exitRoom.y = choosenSide == 2 ? self.height - 1 : 0
}
currentPos.x = exitRoom.x
currentPos.y = exitRoom.y
currentPos.roomsToExit = 1
//print("The exit room is at \(exitRoom.x), \(exitRoom.y)")
mazeData[currentPos.x][currentPos.y] = 15 - direction[choosenSide]
print("The exit room is at [\(exitRoom.x), \(exitRoom.y)] => \(mazeData[currentPos.x][currentPos.y])")
}
init() {
//buildMaze()
}
func update(flag: Int) {
if flag & 1 == 1 {
width = Int(widthDouble)
height = Int(heightDouble)
}
if flag & 2 == 2 {
let viewW = viewWidth/widthDouble
let viewH = viewHeight/heightDouble
let side = (viewW < viewH ? viewW : viewH) - 1.0
self.sideLength = side - side * 0.1
print("Maze init:", width, "x", height, "=", numberOfRooms)
}
ready2Draw = false
}
func dummy() {
let wd = widthDouble
let hd = heightDouble
widthDouble = 3
heightDouble = 3
update(flag: 3)
defineExit()
widthDouble = wd
heightDouble = hd
}
func buildMaze(){
dummy() // This is the only way I found to get the maze displayed correctly
update(flag: 3)
defineExit()
//var rooms = numberOfRooms
//while (rooms > 0) {
// newRoom()
// rooms -= 1
//}
ready2Draw = true
}
func newRoom() {
}
}
//
// ContentView.swift
// NewMaze
//
// Created by Philippe Lagarrigue on 26/12/2020.
//
import SwiftUI
import Combine // << needed for Just publisher below
struct ContentView: View {
#ObservedObject var myMaze: Maze = .init()
#State private var selectedView = 0
let timer = Timer.publish(every: 1, on: .main, in: .common).autoconnect()
var body: some View {
TabView(selection: $selectedView) {
NavigationView() .tabItem { Image("navigation"); Text("Navigation") }.tag(0)
.onReceive(timer) { input in selectedView = 1; self.timer.upstream.connect().cancel() }
SettingsView() .tabItem { Image("settings"); Text("Settings") }.tag(1)
MapView() .tabItem { Image("map"); Text("Map") }.tag(2)
}
//.onReceive(Just(selectedView)) { print($0) }
//.onLongPressGesture { myMaze.ready2Draw = true }
}
}
struct ContentView_Previews: PreviewProvider {
static var previews: some View {
ContentView()
}
}
struct NavigationView : View {
#ObservedObject var myMaze = Maze.sharedInstance
var body : some View {
GeometryReader { geometry in
Path { path in
myMaze.viewWidth = geometry.size.width
myMaze.viewHeight = geometry.size.width
}
}
}
}
struct Square: Shape {
//#ObservedObject var myMaze = Maze.sharedInstance
var value: Int
func path(in rect: CGRect) -> Path {
var path = Path()
if (value & wall.North == wall.North) {
path.move(to: CGPoint(x: rect.minX, y: rect.minY))
path.addLine(to: CGPoint(x: rect.minX, y: rect.maxY))
}
if (value & wall.East == wall.East) {
path.move(to: CGPoint(x: rect.minX, y: rect.maxY))
path.addLine(to: CGPoint(x: rect.maxX, y: rect.maxY))
}
if (value & wall.South == wall.South) {
path.move(to: CGPoint(x: rect.maxX, y: rect.maxY))
path.addLine(to: CGPoint(x: rect.maxX, y: rect.minY))
}
if (value & wall.West == wall.West) {
path.move(to: CGPoint(x: rect.maxX, y: rect.minY))
path.addLine(to: CGPoint(x: rect.minX, y: rect.minY))
}
return path
}
init(value: Int) {
self.value = value
//if value != 15 {
// print("Square: \(value)")
//}
}
}
struct DrawRoom: View {
#ObservedObject var myMaze = Maze.sharedInstance
var xPos: Int
var yPos: Int
let numbers = false
var body: some View {
if numbers {
Text("\(myMaze.value, specifier: "%.02d")")
.font(.system(size: 18, design: .monospaced))
.foregroundColor(myMaze.value == 15 ? Color.black : Color.red)
} else {
Square(value: myMaze.value)
.stroke(Color.gray, style: StrokeStyle(lineWidth: 3))
.frame(width: myMaze.sideLength, height: myMaze.sideLength)
}
}
init(xPos: Int, yPos: Int) {
self.xPos = xPos
self.yPos = yPos
myMaze.value = myMaze.mazeData[xPos][yPos]
print("DrawRoom: [\(xPos), \(yPos)]")
}
}
struct MapView : View {
#ObservedObject var myMaze = Maze.sharedInstance
var body : some View {
if myMaze.ready2Draw {
VStack (spacing: 0) {
ForEach (0..<myMaze.height, id: \.self) { (y: Int) in
HStack (spacing: 0) {
ForEach (0..<myMaze.width, id: \.self) { (x: Int) in
DrawRoom(xPos: x, yPos: y)
} // ForEach x
} // HSTack
} // ForEach y
} // VSTack
} else {
Button(action: { action() }) { Text("Build maze") }
.padding()
.background(Color.red)
.cornerRadius(20)
.foregroundColor(.white)
.font(.title)
.shadow(color: .gray, radius: 20.0, x: 10, y: 10)
}
} // body
func action() {
myMaze.buildMaze()
}
}
struct SettingsView : View {
#ObservedObject var myMaze = Maze.sharedInstance
#State private var isEditing1 = false
#State private var isEditing2 = false
var body : some View {
HStack(alignment: VerticalAlignment.top) {
VStack(alignment: .leading) {
Text("Settings\n") .font(.title)
Text("Number of rooms (horizontally): \(myMaze.widthDouble, specifier: "%.0f")")
.foregroundColor(isEditing1 ? .red : .black)
Slider(value: $myMaze.widthDouble, in: 3...32, step: 1,
onEditingChanged: { editing in isEditing1 = editing })
Text("\nNumber of rooms (vertically): \(myMaze.heightDouble, specifier: "%.0f")")
.foregroundColor(isEditing2 ? .red : .black)
Slider(value: $myMaze.heightDouble, in: 3...32, step: 1,
onEditingChanged: { editing in isEditing2 = editing })
Text("\nIn a maze with only one way, you can find the exit by touching the wall or hedge with the hand nearest to it, left or right. Keep that same hand touching the wall and keep walking. This may take you on a horribly long route, but it will get you out.")
Toggle("One way", isOn: $myMaze.oneWay)
Spacer()
Button(action: { action() }) { Text("Build maze") }
.padding()
.background(Color.red)
.cornerRadius(20)
.foregroundColor(.white)
.font(.title)
.shadow(color: .gray, radius: 20.0, x: 10, y: 10)
Spacer()
} .padding()
}
}
func action() {
myMaze.buildMaze()
}
}