JacksonDunstan.com

static Vector3* AllocOneThousandVectors()
{
	return (Vector3*)Marshal.AllocHGlobal(sizeof(Vector3) * 1000);
}

const int sizeofFloat = sizeof(float);

const int sizeofVector3 = sizeof(Vector3);

const int sizeofVector3 = 12;

using System;
using System.Collections.Generic;
using System.IO;
using System.Reflection;
using System.Runtime.InteropServices;
using UnityEditor;
using UnityEngine;
 
/// <summary>
/// Editor script to generate a C# file containing a static class with the sizes of the value types
/// in the runtime project. 
/// </summary>
/// <author>JacksonDunstan.com/articles/3921</author>
/// <license>MIT</license>
public class GenerateTypeSizes
{
	[MenuItem("Code Generators/Type Sizes")]
	public static void Generate()
	{
		// Find the assembly with the runtime code
		Assembly runtimeAssembly = null;
		foreach (Assembly assembly in AppDomain.CurrentDomain.GetAssemblies())
		{
			if (assembly.FullName.StartsWith("Assembly-CSharp,"))
			{
				runtimeAssembly = assembly;
				break;
			}
		}
		if (runtimeAssembly == null)
		{
			Debug.LogError("Couldn't find runtime assembly. No generating code.");
			return;
		}
 
		// Overwrite the output file
		const string outputClassName = "TypeSizes";
		string path = Path.Combine(Application.dataPath, outputClassName) + ".cs";
		using (FileStream stream = File.OpenWrite(path))
		{
			// Clear the existing file
			stream.SetLength(0);
			stream.Flush();
 
			// Write the sizes
			// Also make a list of constant types
			List<Type> constTypes = new List<Type>(1024);
			StreamWriter writer = new StreamWriter(stream);
			writer.Write("////////////////////////////////////////\n");
			writer.Write("// Autogenerated code! Do not modify! //\n");
			writer.Write("////////////////////////////////////////\n");
			writer.Write('\n');
			writer.Write("unsafe public static class ");
			writer.Write(outputClassName);
			writer.Write('\n');
			writer.Write("{\n");
			foreach (Type type in runtimeAssembly.GetTypes())
			{
				// Only output value types
				// Skip the output type itself
				// Skip enums
				if (type.IsValueType && !type.IsEnum && type.Name != outputClassName)
				{
					// Make sure it doesn't have any non-value field types except pointers
					bool hasPointers = false;
					foreach (FieldInfo field in type.GetFields())
					{
						bool isPointer = field.FieldType.IsPointer;
						if (isPointer)
						{
							hasPointers = true;
						}
						if (!field.FieldType.IsValueType && !isPointer)
						{
							Debug.LogWarningFormat(
								"{0}.{1} is a {2}, which is not a value type. Not outputting size.",
								type.Name,
								field.Name,
								field.FieldType);
							goto continueOuterLoop;
						}
					}
 
					writer.Write("\tpublic ");
 
					// The size of a pointer differs by CPU architecture (e.g. 32-bit vs. 64-bit)
					// We're forced to use sizeof(MyStruct) to determine it at runtime
					if (hasPointers)
					{
						writer.Write("static readonly uint ");
						writer.Write(type.Name);
						writer.Write(" = (uint)sizeof(");
						writer.Write(type.Name);
						writer.Write(')');
					}
					// The size of structs with no pointers and only value types can be
					// determined by Marshal.SizeOf.
					else
					{
						writer.Write("const uint ");
						writer.Write(type.Name);
						writer.Write(" = ");
						writer.Write(Marshal.SizeOf(type));
						constTypes.Add(type);
					}
 
					writer.Write(";\n");
				}
				continueOuterLoop:;
			}
 
			// Output static constructor to check that constants are valid when run in editor
			writer.Write("\t\n");
			writer.Write("#if UNITY_EDITOR\n");
			writer.Write("\tstatic ");
			writer.Write(outputClassName);
			writer.Write("()\n");
			writer.Write("\t{\n");
			writer.Write("\t\tif (\n");
			for (int i = 0, len = constTypes.Count; i < len; ++i)
			{
				Type type = constTypes[i];
				writer.Write("\t\t\t");
				writer.Write(type.Name);
				writer.Write(" != sizeof(");
				writer.Write(type.Name);
				writer.Write(")");
				if (i != len - 1)
				{
					writer.Write(" ||\n");
				}
				else
				{
					writer.Write(")\n");
				}
			}
			writer.Write("\t\t{\n");
			writer.Write(
				"\t\t\tUnityEngine.Debug.LogError(\"TypeSizes is stale. Re-run code generator.\");\n");
			writer.Write("\t\t\tUnityEditor.EditorApplication.isPlaying = false;\n");
			writer.Write("\t\t}\n");
			writer.Write("\t}\n");
			writer.Write("#endif\n");
 
			// End the file
			writer.Write("}\n");
			writer.Flush();
		}
 
		// Done
		AssetDatabase.Refresh();
		Debug.LogFormat("Successfully generated {0}.cs", outputClassName);
	}
}