SKPath Iterator Benchmarks

Program.cs

using System;
using System.Collections.Generic;
using BenchmarkDotNet.Attributes;
using BenchmarkDotNet.Jobs;
using BenchmarkDotNet.Running;

namespace SkiaSharp.Benchmarks
{
	//[SimpleJob(RuntimeMoniker.CoreRt31)]
	[SimpleJob(RuntimeMoniker.Mono)]
	[SimpleJob(RuntimeMoniker.Net472)]
	[SimpleJob(RuntimeMoniker.NetCoreApp31)]
	[SimpleJob(RuntimeMoniker.NetCoreApp50)]
	[MemoryDiagnoser]
	public unsafe class Benchmark
	{
		private List<SKPath> _paths = new List<SKPath>();

		public Benchmark()
		{
			var random = new Random();
			// setup
			for (var i = 0; i < 100; i++)
			{
				var path = new SKPath();
				for (var l = 0; l < 100; l++)
				{
					path.LineTo((float)random.NextDouble(), (float)random.NextDouble());
				}
				_paths.Add(path);
			}
		}

		[Benchmark(Description = "iterator.Next(new SKPoint[])", Baseline = true)]
		public void ExistingRawIterator()
		{
			// benchmark
			foreach (var path in _paths)
			{
				using var iterator = path.CreateRawIterator();
				var span = new Span<SKPoint>(new SKPoint[4]);
				while (true)
				{
					var verb = iterator.Next(span);
					if (verb == SKPathVerb.Done)
					{
						break;
					}
				}
			}
		}

		[Benchmark(Description = "SkiaApi.sk_path_rawiter_next(new SKPoint[])")]
		public void SkiaApiRawIterator()
		{
			// benchmark
			foreach (var path in _paths)
			{
				using var iterator = path.CreateRawIterator();
				var span = new Span<SKPoint>(new SKPoint[4]);
				fixed (SKPoint* p = span)
				{
					while (true)
					{
						var verb = SkiaApi.sk_path_rawiter_next(iterator.Handle, p);
						if (verb == SKPathVerb.Done)
						{
							break;
						}
					}
				}
			}
		}

		[Benchmark(Description = "iterator.Next(new SKPoint*)")]
		public void NewRawIterator()
		{
			// benchmark
			foreach (var path in _paths)
			{
				using var iterator = path.CreateRawIterator();
				fixed (SKPoint* p = new SKPoint[4])
				{
					while (true)
					{
						var verb = SkiaApi.sk_path_rawiter_next(iterator.Handle, p);
						if (verb == SKPathVerb.Done)
						{
							break;
						}
					}
				}
			}
		}


		[Benchmark(Description = "iterator.Next(stackalloc SKPoint[])")]
		public void StackAllocExistingRawIterator()
		{
			// benchmark
			foreach (var path in _paths)
			{
				using var iterator = path.CreateRawIterator();
				Span<SKPoint> span = stackalloc SKPoint[4];
				while (true)
				{
					var verb = iterator.Next(span);
					if (verb == SKPathVerb.Done)
					{
						break;
					}
				}
			}
		}

		[Benchmark(Description = "SkiaApi.sk_path_rawiter_next(stackalloc SKPoint[])")]
		public void StackAllocSkiaApiRawIterator()
		{
			// benchmark
			foreach (var path in _paths)
			{
				using var iterator = path.CreateRawIterator();
				var span = stackalloc SKPoint[4];
				while (true)
				{
					var verb = SkiaApi.sk_path_rawiter_next(iterator.Handle, span);
					if (verb == SKPathVerb.Done)
					{
						break;
					}
				}
			}
		}

		[Benchmark(Description = "iterator.Next(stackalloc SKPoint*)")]
		public void StackAllocNewRawIterator()
		{
			// benchmark
			foreach (var path in _paths)
			{
				using var iterator = path.CreateRawIterator();
				var span = stackalloc SKPoint[4];
				while (true)
				{
					var verb = iterator.Next(span);
					if (verb == SKPathVerb.Done)
					{
						break;
					}
				}
			}
		}
	}

	public class Program
	{
		public static void Main(string[] args)
		{
			var summary = BenchmarkRunner.Run<Benchmark>();
		}
	}
}