How to Use XDRE (Video Guide)

[RockyGaming4725]

Welcome!
I'm aware of the existing guide well written by @almostmatt1. It deserves to be linked here even if it is a bit older because it does cover some things this guide does not. This guide simply goes over navigation of the main window, and helps you build a demo (Doom II Map 01, no monsters) from scratch using XDRE.

While the momentum preservation trick (also known as a door trick) is covered, it's important to note that this guide does not go over:

• Brute force usage
• Every keybind/command (such as transposing commands)
• How to perform/brute force tricks, such as wallruns, wobbles (.000000 tricks), glides, lineskips, etc.
• Optimization strategies such as smooth turning around corners or approaches to switches/doors
• In-depth technical explanations of engine gimmicks

 

What this guide does go over:

• How to navigate XDRE (move forward, move backward, jump backward/forward)
• How to load demos, iwads, pwads
• How to edit inputs
• How to create new/empty tics
• What every box and number in the main window means
• How to edit a demo header
• How to perform a momentum preservation trick
• How to save a demo
• Some other little tips and things

 

I highly recommend reading the Doom Movement Bible written by @Linguica for highly in-depth explanations to some of the tricks listed above. It is a bit old now, and many TAS exclusive tricks still remain hidden in the dark when it comes to explanations or even general exposure.

 

Before watching the guide, I recommend reading the section below. It provides some background information on XDRE, TASing, Doom terms, etc. by answering some questions I think might get asked. Feel free to jump around and skip things.

Spoiler

What is XDRE?
        XDRE (Xepop's Doom Replay Editor) is a Doom TASing program. It allows the user to view and/or edit inputs of individual tics/frames of Doom demos. The demos created by XDRE are still "valid" in terms of replayability. Think of the resulting demo as a standard demo, just very finely tuned for exceptional precision. There is no magic - you cannot tell an enemy to go one way, or get max damage rolls every shot (RNG will still mess with you just as hard, if not harder). All you have control of is the player, although thanks to the tic-by-tic editing style, you can rewind and fine tune everything to be as close to perfect as you want.
        While XDRE has a bit of a learning curve, many things can be self-taught. However, to try to streamline this process, I created the video guide listed below. Once you can navigate XDRE, and understand everything in there, it becomes a bit easier. I also plan on releasing more videos covering multiple topics, and I'll update the thread with these as they release.

 

What is TASing?

        TAS stands for tool-assisted speedruns. As the name states, a tool-assisted speedrun is a speedrun created with the aid of tools. Whether that's as simple as using saves, it could also be frame-by-frame editing (which is what XDRE does!). TASing just means making these tool-assisted runs.

 

Why would I want to TAS Doom?

        While non-TASes of Doom can certainly be very fast, TASes can be even faster. Both of these runs included extensive amounts of time, effort, and commitment to achieve. These are both equally impressive demos and demand very high amounts of respect. However, speedrunning Doom with and without tools are two completely different things. I feel a bit hypocritical having put a comparison in the first sentence here, but hey, it was a nice hook :)
        TASes are not comparable to regular speedruns. Period. Each require different skillsets and knowledge. If you only think TASes are more valuable because they are faster, I'm sorry, but that is a very poor opinion. And if you think non-TASes are more valuable only because a human is actually performing them in real-time, I'm sorry again, because that is a poor opinion. It's not just to compare the two like that. Obviously you can hold an opinion on which you find more impressive, more entertaining, more respectable and valuable, however I do recommend looking past the surface. I cannot speak for TASes outside of Doom, nor can I even speak for non-built Doom TASes (demos using slo-mo and rewinds, for example) but in the Doom world (heh) both categories of speedruns demand respect. The fact is that they are different skillsets. Bad analogy coming up, but imagine two people are hired to throw an (American) football across a field. One is told they can only throw it themself, while the other is told they are allowed to design a machine to throw it for them. Two completely different tasks, both requiring their own time, effort, and varying areas of expertise.

        In my opinion, there's no point comparing the two, in any regard, other than for pure fun.

        Alright, coming back from the tangent, why would someone even TAS Doom? Well... it may be easier to answer this with my own reason. I started TASing because I wanted to see how fast a certain level could be. I was curious. Well... it's safe to say I was quite far off from how fast it could actually be (different categories, but that doesn't really matter here. Okay? Okay). Why did I stick with it, though? I found it fun trying to go as fast as I thought was possible. Not humanly, I wanted more. When human skills are just not enough (hehe). I ended up learning so much more about the game and I was so intrigued by how some demos were just so fully optimized. All in all, I found I wasn't hooked by just trying to faster, or even as fast as possible, but by learning more about the game's engine quirks and how to exploit them. That's my story, you can go ahead and clap now...

        TLDR you can go really fast and it teaches you a lot (but still leaves you in the dark often times) about the game's engine oddities.

 

What the hell is a tic?

        A "tic" simply refers to any individual frame of a Doom demo. While source ports allow for uncapped framerates, the game's actual logic is only run 35 times per second. This means there are 35 "tics" in a single second. Not good enough? Here...

 

Is TASing Doom easy?

        Yes, and no. It's very easy to TAS Doom, but incredibly difficult to master. I truthfully think no one will ever create a demo that is perfect. TASing is a strive for absolute perfection, but one that never gets there. Sure... the time limit for e1m1 has probably been reached at 7.69, but hell, maybe a few units could be saved. No? At least a little bit. But at what point does it even then matter? That's up to you.

 

Oh, I need to include this here too.

CHEATING

        Using XDRE to create a demo and pass it off as genuine is cheating. Don't do it.
        That can range from getting an exit switch press just a tad bit earlier to adding a few empty tics on the intermission screen.
--> ANY EDITING OF A DEMO USING XDRE MAKES IT INVALID FOR NON-TAS SUBMISSION TO DSDA. <--

        Using XDRE to edit a demo instantly makes it a TAS. No matter how small the edit is. Do not use XDRE to cheat. You'll get caught too.

 

Warning: Teenage voice present

Watch the guide here - 

I'm going to leave this post for a bit and might not check it for a while. Typos? Grammar? Pft...

[besus]

nice this is an awesome guide i love it thanks cant wait to see more arcane tasing knowledge from either you or matt

 

Spoiler