unity-debug-overlay

A fast and (almost) garbage free debug overlay for Unity. The projects contains two primary components: a debug overlay and a console.

Performance

Garbage production is minimized by not really using strings a lot and by having convenience functions that mimick string formatting (using format strings like "This: {0}") known from C#. Rendering happens through the magic of a few procedural draw calls and is quite fast.

Debug overlay

The debug overlay is useful for displaying text and graphs that update every frame. Like this:

This can be done with some level of convenience using this code:

    // FPS in top left corner
    DebugOverlay.Write(1, 0, "FPS:{0,6:###.##}", 1.0f / Time.deltaTime);

    // Small graph of FPS below
    fpsHistory[Time.frameCount % fpsHistory.Length] = 1.0f / Time.deltaTime;
    DebugOverlay.DrawGraph(1, 1, 9, 1.5f, fpsHistory, Time.frameCount % fpsHistory.Length, Color.green);

Even though it looks like regular string formatting, no garbage will be generated.

Console

The console is useful for checking logs / output while ingame and also for easily registrering commands that can be used to tweak the game behaviour or turn on/off debugging aspects.

You can write

    // Register quit command
    Game.console.AddCommand("quit", CmdQuit, "Quit game");

    /* ... */

    void CmdQuit(string[] args)
    {
    	Game.console.Write("Goodbye\n");
        Application.Quit();
    }

and it will work like this: