SimpleProfilerWindow.cs

using System;
using System.Collections.Generic;
using System.Linq;
using UnityEngine;
using UnityEditor;
using UnityEngine.Profiling;


class SimpleProfilerWindow : EditorWindow
{
	const int sampleCount = 100; // width of the texture and also sample buffer size
	const int height = 30; // height of the texture
	const float delay = 0.5f;

	Texture2D _waveform;
	static FixedSizedListBuffer<long> samples;
	Color32[] _clear;
	float _counter;
	
	[MenuItem("Joon/Profiling/Show Simple Profiler Window")]
	public static void ShowWindow()
	{
		var window = (SimpleProfilerWindow) GetWindow(typeof(SimpleProfilerWindow));
		window.titleContent.text = "Memory Profiler";
		window.Show();
	}

	void OnEnable()
    {
	    if (_waveform != null) DestroyImmediate(_waveform);
	    Repaint();
    }

    void OnGUI()
    {
	    if (_waveform == null) 
	    {
		    _waveform = new Texture2D(sampleCount, height, TextureFormat.RGBA32, false);
		    _waveform.filterMode = FilterMode.Point;
		    if(samples == null) samples = new FixedSizedListBuffer<long>(sampleCount);
	    }
	    
	    if (_clear == null)
	    {
		    _clear = new Color32[_waveform.GetPixels32().Length];
		    for (int i = 0; i < _clear.Length; i++)
		    {
			    _clear[i] = new Color32(200,200,200,255);
		    }
	    }


	    long max = 0;
	    long last = 0;
	    if (samples.Count > 0)
	    {
		    max = samples.Max();
		    last = samples.Last();
	    }
	    
	    _waveform.SetPixels32(_clear);
	    for (int i = 0; i < samples.Count; i++)
	    {
		    var y = (int) (samples[i] / (max *1.2f) * height);

		    for (int j = 0; j < y; j++)
		    {
			    _waveform.SetPixel(i,j, Color.white);    
		    }
		    
	    }
	    _waveform.Apply();
		
	    EditorGUI.DrawPreviewTexture(new Rect(0, 0, (int) position.width, (int) position.height), _waveform);
	    GUILayout.Label("current: " + FormatBytes(last));
	    GUILayout.Label("max: " + FormatBytes(max));

    }

    void Update()
    {
	    if (_counter + delay < Time.realtimeSinceStartup)
	    {
		    _counter = Time.realtimeSinceStartup;
		    
		    if(samples == null) samples = new FixedSizedListBuffer<long>(sampleCount);
		    samples.Add(GetCurrentValue());
		    Repaint();
	    }
    }
    
    // https://stackoverflow.com/questions/1242266/converting-bytes-to-gb-in-c/25395808#25395808
    private static string FormatBytes(long bytes)
    {
	    string[] Suffix = { "B", "KB", "MB", "GB", "TB" };
	    int i;
	    double dblSByte = bytes;
	    for (i = 0; i < Suffix.Length && bytes >= 1024; i++, bytes /= 1024) 
	    {
		    dblSByte = bytes / 1024.0;
	    }

	    return String.Format("{0:0.##} {1}", dblSByte, Suffix[i]);
    }

    long GetCurrentValue()
    {
	    return Profiler.GetAllocatedMemoryForGraphicsDriver();
    }
    
    public class FixedSizedListBuffer<T> : List<T>
    {
	    public int size { get; private set; }

	    public FixedSizedListBuffer(int size)
	    {
		    this.size = size;
	    }

	    public new void Add(T obj)
	    {
		    base.Add(obj);
		    if(Count > size) RemoveAt(0);
	    }
    }
}