Add 360 degree node viewer

Author: jnm2

MystIVAssetExplorer/Extensions.cs

@@ -0,0 +1,32 @@
+using System;
+using System.Collections.Generic;
+using System.Diagnostics.CodeAnalysis;
+using System.Linq;
+
+namespace MystIVAssetExplorer;
+
+internal static class Extensions
+{
+    public static bool TrySingle<T>(this IEnumerable<T> source, [MaybeNullWhen(false)] out T single)
+    {
+        using var enumerator = source.GetEnumerator();
+
+        if (enumerator.MoveNext())
+        {
+            var current = enumerator.Current;
+            if (!enumerator.MoveNext())
+            {
+                single = current;
+                return true;
+            }
+        }
+
+        single = default;
+        return false;
+    }
+
+    public static bool TrySingle<T>(this IEnumerable<T> source, Func<T, bool> predicate, [MaybeNullWhen(false)] out T single)
+    {
+        return source.Where(predicate).TrySingle(out single);
+    }
+}

MystIVAssetExplorer/Formats/ZapImage.cs

@@ -0,0 +1,35 @@
+using MystIVAssetExplorer.Memory;
+using System;
+
+namespace MystIVAssetExplorer.Formats;
+
+public sealed class ZapImage
+{
+    public required int Width { get; init; }
+    public required int Height { get; init; }
+    public required ReadOnlyMemory<byte> RgbChannels { get; init; }
+    public required ReadOnlyMemory<byte> AlphaChannel { get; init; }
+
+    public static ZapImage Parse(ReadOnlyMemory<byte> zapFileData)
+    {
+        var reader = new SpanReader(zapFileData.Span);
+        if (reader.ReadUInt32LittleEndian() != 32) throw new NotImplementedException();
+        if (reader.ReadUInt32LittleEndian() != 2) throw new NotImplementedException();
+        if (reader.ReadUInt32LittleEndian() != 10) throw new NotImplementedException();
+        if (reader.ReadUInt32LittleEndian() != 10) throw new NotImplementedException();
+        var dataLength1 = reader.ReadInt32LittleEndian();
+        var dataLength2 = reader.ReadInt32LittleEndian();
+        var width = reader.ReadInt32LittleEndian();
+        var height = reader.ReadInt32LittleEndian();
+
+        var position = zapFileData.Length - reader.Span.Length;
+        var image1 = zapFileData.Slice(position, dataLength1);
+        position += dataLength1;
+        var image2 = zapFileData.Slice(position, dataLength2);
+        position += dataLength2;
+        if (position != zapFileData.Length)
+            throw new NotImplementedException();
+
+        return new ZapImage { Width = width, Height = height, RgbChannels = image1, AlphaChannel = image2 };
+    }
+}

MystIVAssetExplorer/ILease.cs

@@ -0,0 +1,8 @@
+using System;
+
+namespace MystIVAssetExplorer;
+
+public interface ILease<out T> : IDisposable
+{
+    T LeasedInstance { get; }
+}

MystIVAssetExplorer/MystIVAssetExplorer.csproj

@@ -15,6 +15,7 @@
     <PackageReference Include="Avalonia.Controls.DataGrid" Version="$(AvaloniaVersion)" />
     <PackageReference Include="Avalonia.Fonts.Inter" Version="$(AvaloniaVersion)" />
     <PackageReference Include="Avalonia.ReactiveUI" Version="$(AvaloniaVersion)" />
+    <PackageReference Include="Avalonia.Skia" Version="$(AvaloniaVersion)" />
     <PackageReference Include="FluentIcons.Avalonia" Version="1.1.303" />
     <!--Condition below is needed to remove Avalonia.Diagnostics package from build output in Release configuration.-->
     <PackageReference Condition="'$(Configuration)' == 'Debug'" Include="Avalonia.Diagnostics" Version="$(AvaloniaVersion)" />

MystIVAssetExplorer/ReferenceCountedDisposable.cs

@@ -0,0 +1,61 @@
+using System;
+using System.Threading;
+
+namespace MystIVAssetExplorer;
+
+public sealed class ReferenceCountedDisposable<T> where T : IDisposable
+{
+    private readonly object lockObject = new();
+    private T? instance;
+    private int referenceCount = 1;
+
+    public ReferenceCountedDisposable(T instance, out ILease<T> initialLease)
+    {
+        this.instance = instance;
+        initialLease = new DecrementLease(this);
+    }
+
+    public ILease<T>? TryLease()
+    {
+        lock (lockObject)
+        {
+            if (referenceCount == 0)
+                return null;
+
+            referenceCount++;
+            return new DecrementLease(this);
+        }
+    }
+
+    private void Decrement()
+    {
+        var shouldDispose = false;
+        var instanceToDispose = default(T);
+
+        lock (lockObject)
+        {
+            if (referenceCount == 0)
+                throw new InvalidOperationException("More increments than decrements");
+
+            referenceCount--;
+            if (referenceCount == 0)
+            {
+                shouldDispose = true;
+                instanceToDispose = instance;
+                instance = default;
+            }
+        }
+
+        if (shouldDispose)
+            instanceToDispose!.Dispose();
+    }
+
+    private sealed class DecrementLease(ReferenceCountedDisposable<T> owner) : ILease<T>
+    {
+        private ReferenceCountedDisposable<T>? owner = owner;
+
+        public T LeasedInstance => (Volatile.Read(ref owner) ?? throw new ObjectDisposedException(nameof(ILease<>))).instance!;
+
+        public void Dispose() => Interlocked.Exchange(ref owner, null)?.Decrement();
+    }
+}

MystIVAssetExplorer/Skybox/SkyboxControl.CheckerboardOperation.cs

@@ -0,0 +1,55 @@
+using Avalonia;
+using Avalonia.Media;
+using Avalonia.Platform;
+using Avalonia.Rendering.SceneGraph;
+using Avalonia.Skia;
+using SkiaSharp;
+using System;
+
+namespace MystIVAssetExplorer.Skybox;
+
+partial class SkyboxControl
+{
+    private sealed class CheckerboardDrawOperation : ICustomDrawOperation
+    {
+        private readonly SkyboxControl owner;
+        private readonly SKBitmap checkerboardTileBitmap;
+        private readonly SKShader checkerboardShader;
+        private readonly SKPaint checkerboardPaint;
+
+        public CheckerboardDrawOperation(SkyboxControl owner)
+        {
+            this.owner = owner;
+
+            checkerboardTileBitmap = new SKBitmap(2, 2);
+            checkerboardTileBitmap.SetPixel(0, 0, new SKColor(0x55, 0x55, 0x55));
+            checkerboardTileBitmap.SetPixel(1, 0, new SKColor(0x33, 0x33, 0x33));
+            checkerboardTileBitmap.SetPixel(0, 1, new SKColor(0x33, 0x33, 0x33));
+            checkerboardTileBitmap.SetPixel(1, 1, new SKColor(0x55, 0x55, 0x55));
+
+            checkerboardShader = SKShader.CreateBitmap(checkerboardTileBitmap, SKShaderTileMode.Repeat, SKShaderTileMode.Repeat, SKMatrix.CreateScale(8, 8));
+            checkerboardPaint = new SKPaint { Shader = checkerboardShader };
+        }
+
+        public Rect Bounds => new(owner.Bounds.Size);
+
+        public void Render(ImmediateDrawingContext context)
+        {
+            using var lease = context.TryGetFeature<ISkiaSharpApiLeaseFeature>()!.Lease();
+            var canvas = lease.SkCanvas;
+
+            canvas.DrawRect(new SKRect(0, 0, (float)Bounds.Width, (float)Bounds.Height), checkerboardPaint);
+        }
+
+        public void Dispose()
+        {
+            checkerboardPaint.Dispose();
+            checkerboardShader.Dispose();
+            checkerboardTileBitmap.Dispose();
+        }
+
+        bool IEquatable<ICustomDrawOperation>.Equals(ICustomDrawOperation? other) => other == this;
+
+        bool ICustomDrawOperation.HitTest(Point p) => Bounds.Contains(p);
+    }
+}