Things about Doom you just found out

[galileo31dos01]

Hard to explain but here it goes.

 

When things that are there become invisible depending on the angle where you see them. It isn't the first time I see this, but it intrigues me immensely to know the reasons. A few examples:

 

Spoiler

Map 07 of Eternal Doom

 

Depending on where I stand, things are visible or not.

 

 

Spoiler

Map 08 of Legacy of Heroes.

 

First picture, box of rockets and a silent manc. Second picture, moved a bit to the side and they were gone, well not really.

 

 

Hope someone could enlighten me about this phenomenon. 

[crazyflyingdonut]

That hidden in the source code for Doom 2 had some code that was meant to be used for sliding doors, (specifically, for the Wolfenstein 3D doors). I saw a video of it, and it looked so cool!

 

Also, I've read that hidden in Doom 1's source code is an unfinished easter egg where it turns the map into Asteroids (that Atari game), but there wasn't much code for the easter egg to actually do anything. I don't know if this is true or not, because I read it on TCRF and it doesn't seem like something that the Doom engine could do.

[Edward850]

2 hours ago, crazyflyingdonut said:

Also, I've read that hidden in Doom 1's source code is an unfinished easter egg where it turns the map into Asteroids (that Atari game), but there wasn't much code for the easter egg to actually do anything. I don't know if this is true or not, because I read it on TCRF and it doesn't seem like something that the Doom engine could do.

Dave Taylor originally started development of automap asteroids, however it was never finished and didn't get very far. However there is no reason why the automap couldn't have done this, seeing as the automap is simple vector drawings, as is asteroids.

https://doomwiki.org/wiki/Automap_asteroids

[Nevander]

I only recently learned that Doom 64 will round up your health/ammo/armor by the next 25 when a saved password is loaded. For example, if you end a level with 186 health and then re-load the password, it will be 200. Likewise, ending with 167 will be 175 when loaded. That's a nice thing to know when planning your amounts for starting the next level.

[Vermil]

11 hours ago, galileo31dos01 said:

Hard to explain but here it goes.

 

When things that are there become invisible depending on the angle where you see them. It isn't the first time I see this, but it intrigues me immensely to know the reasons. A few examples:

 

  Reveal hidden contents

Map 07 of Eternal Doom

 

Depending on where I stand, things are visible or not.

 

 

  Reveal hidden contents

Map 08 of Legacy of Heroes.

 

First picture, box of rockets and a silent manc. Second picture, moved a bit to the side and they were gone, well not really.

 

 

Hope someone could enlighten me about this phenomenon. 

 

If I recall correctly (?), Vanilla Doom clips sprites when it thinks you can no longer see the sector that the middle of a mobj is in. Rendering hacks can confuse this behaviour though.

[Gez]

Yes, sprites disappear if you cannot see the subsector in which the sprite's mobj is located. For large sprites, this can cause this kind of blinking.

 

In GZDoom, this is alleviated because it'll take the mobj's radius into account, not just the mobj's center. You can even define a RenderRadius so that the collision box doesn't need to conform to the sprite size.

[BrassKnight]

Something I've noticed while playing The Shores Of Hell episode in Doom is that the more the player progress throughout the episode, the more the Tower of Babel gets finished. Here's a gif of it:

 

 

[Chezza]

3 hours ago, BrassKnight said:

Something I've noticed while playing The Shores Of Hell episode in Doom is that the more the player progress throughout the episode, the more the Tower of Babel gets finished. Here's a gif of it:

 

 

What!? That blows my mind! Why? Was it being summoned or built? Someone explain this lore to me.

[Maser]

Kind of disappointing that the Tower Of Babel doesn't have a tower to climb. Also, isn't that level the first time in the whole Doom series we meet the Cyberdemon for the first time?

[TakenStew22]

2 hours ago, Maser said:

Also, isn't that level the first time in the whole Doom series we meet the Cyberdemon for the first time?

Yes.

[kb1]

On 9/24/2018 at 11:15 PM, Nevander said:

I only recently learned that Doom 64 will round up your health/ammo/armor by the next 25 when a saved password is loaded. For example, if you end a level with 186 health and then re-load the password, it will be 200. Likewise, ending with 167 will be 175 when loaded. That's a nice thing to know when planning your amounts for starting the next level.

This was almost surely a decision by the developers to be fair. The password itself is being used as a poor man's save game file. You said the rounding was based on 25. To encode a health value from 1 to 200, in steps of 25, takes 3 bits of storage (each bit being a 0 or 1):

 

The formula for encoding health is something like this:

• Add 24 to the health: X = Health + 24   (for 167, X = 191)
• Divide this value by 25: X = (X / 25)   (X = 7.64)
• Drop the fraction, leaving an integer: X = INT(X)   (X = 7)
• Convert to binary, and discard all but the lower 3 bits: X = 111b

One caveat: I don't know if Doom 64 allows health to be 200, vs 199. But, if so, this special case will be encoded by the above formula as X = 000b.

 

The formula for decoding health is something like (assuming A, B, and C are the 3 bits:

• Convert the 3 binary bits to decimal: X = (A * 100) + (B * 50) + (C * 25)
• If X = 0, Set X = 200.

Armor can be encoded the same way. Ammo requires more bits.

 

So this password not only unlocks the map level, it also encodes enough information to approximate the player stats, and some sort of checksum to prevent every possible combination from being a legal password. Certainly not ideal, but not bad for not using any storage medium whatsoever :)

 

[zokum]

Doom 64 uses a classic technique. The Lemmings games used a similar scheme, you can find some info about it here: http://www.the-spoiler.com/OTHER/Psygnosis/lemmings.2.html

[Phoby]

Chainsaw is really good against pain elementals.

[elend]

I recently found out that you can use the stair builder in GzDoom Builder to make actual outlines. Why was I never thinking of that? Should be called "outline mode" maybe, instead of stair builder. Additionally to that, you can use it to extrude single linedefs. Say, you want and indentation in a wall that is at an odd angle. Helps so much.

 

Are there more tricks like that? I bet, but how the hell am I supposed to learn about them? :p

[DavidN]

^ That's incredible! I've been making wonky alcoves the whole time and just hoping the player won't notice - in fact I'd considered writing an "alcove builder" as a push request, but this does everything I would need it to.

[Dragonfly]

@elend I think it's you who's been leaving comments on my stream VODs lately, right? :D

 

Using a combination of stair builder and curve linedef tools, you can make pretty much any shaped structure. One thing to note: The stair builder tool behaves differently based on if you're in lines mode or sectors mode - try using both modes for different uses. :D

 

[Bridgeburner56]

I just found out that the stair build tool functions differently depending on mode

[elend]

@Dragonfly Yes indeed that‘s me. Catching up with your library right now and discovered this in your 8 hour (?!) Eviternity Mapping stream. It‘s a joy to watch you map. 

 

That curve tool is already being abused by me in my new map. The theme is „Hell“ and no single linedef makes any sense. 

 

Also I noticed how you drag vertices only when you want to copy a shape over another shape. I always copied the entire sector and yes, it most often than not royally fucks up my map. So thanks for that idea as well! :D

 

@everybody else: Check out Dragonfly‘s Mapping videos. You‘ll learn a lot (and have some fun while doing so).

[Koko Ricky]

11 hours ago, elend said:

I recently found out that you can use the stair builder in GzDoom Builder to make actual outlines. Why was I never thinking of that? Should be called "outline mode" maybe, instead of stair builder. Additionally to that, you can use it to extrude single linedefs. Say, you want and indentation in a wall that is at an odd angle. Helps so much.

 

Are there more tricks like that? I bet, but how the hell am I supposed to learn about them? :p

Can you go into detail? I've never understood the stair builder.

[Dragonfly]

@GoatLord @elend

 

This conversation has prompted me to work on a tutorial. Using some remaining lunch break I knocked up some content, I'll have to fact-check, get images etc another time as I'm currently at work, but hopefully this is enough to get you started!

 

https://www.dfdoom.com/tutorial-utilising-the-stair-builder-curve-tool-to-save-time/

[elend]

 

 

Of course. Open your GzDoom Builder and create a sector. Select this sector and open the stair builder. The rest should be rather self explanatory. But it basically creates another sector at a given distance either within or outside the selected sector. This can be repeated in steps as well, according to what you tell it to do. 

 

As for the stair builder in linedefs mode, just select a linedef and then the stairs builder. You‘ll see the result and what I mean immediately.

 

Edit; Also check out Dragonfly‘s tutorial. xD

[Jaska]

On 10/2/2018 at 4:17 AM, elend said:

I recently found out that you can use the stair builder in GzDoom Builder to make actual outlines. Why was I never thinking of that? Should be called "outline mode" maybe, instead of stair builder. Additionally to that, you can use it to extrude single linedefs. Say, you want and indentation in a wall that is at an odd angle. Helps so much.

 

Are there more tricks like that? I bet, but how the hell am I supposed to learn about them? :p

 

Madness! This is what I've missed and it has always been there... Thanks!

[TakenStew22]

I also found out about a month ago that the area-of-effect of a BFG shot will come with you and do more damage the closer you are to the enemy. Now I know why alot of speedrunners do that.

[zokum]

21 hours ago, TakenStew22 said:

I also found out about a month ago that the area-of-effect of a BFG shot will come with you and do more damage the closer you are to the enemy. Now I know why alot of speedrunners do that.

The distance doesn't matter. How many rays that hit is all that matters. In a crowded room with monsters covering the screen, all rays will easily hit something.

The BFG is not an area of effect weapon, it is a single target projectile + a shotgun like spread from the player when the ball detonates. If you are very close to a monster, and the angle is right, all the tracers will hit that monster. Range does not play a part. It's all about statistics, it's easier to not waste any rays when you got the screen covered with a single monster, and the effect is also more noticable.

[TakenStew22]

28 minutes ago, zokum said:

The distance doesn't matter. How many rays that hit is all that matters. In a crowded room with monsters covering the screen, all rays will easily hit something.

The BFG is not an area of effect weapon, it is a single target projectile + a shotgun like spread from the player when the ball detonates. If you are very close to a monster, and the angle is right, all the tracers will hit that monster. Range does not play a part. It's all about statistics, it's easier to not waste any rays when you got the screen covered with a single monster, and the effect is also more noticable.

I am... so confused. But thanks for the info.

[Nevander]

53 minutes ago, zokum said:

The distance doesn't matter. How many rays that hit is all that matters. In a crowded room with monsters covering the screen, all rays will easily hit something.

The BFG is not an area of effect weapon, it is a single target projectile + a shotgun like spread from the player when the ball detonates. If you are very close to a monster, and the angle is right, all the tracers will hit that monster. Range does not play a part. It's all about statistics, it's easier to not waste any rays when you got the screen covered with a single monster, and the effect is also more noticable.

I would argue that range does affect which rays hit what, however. If you were 1024 units away from a Baron vs 32 units away, it will matter. Less rays will hit because of the distance being farther away. The cone of rays will be spread out instead of focused.

[Dragonfly]

This guide, with it's visual explanations, is much better than words.

 

https://www.zdaemon.org/starterguide/BFG.htm

 

Take a look, @TakenStew22. :)

[damerell]

56 minutes ago, Nevander said:

I would argue that range does affect which rays hit what, however.

Does that need to be argued? No-one is suggesting it's not the case, and it seems rather self-evident.

[TakenStew22]

1 hour ago, Dragonfly said:

This guide, with it's visual explanations, is much better than words.

 

https://www.zdaemon.org/starterguide/BFG.htm

 

Take a look, @TakenStew22. :)

Interesting, I think I get it now. Thanks!

[Dragonfly]

15 minutes ago, damerell said:

Does that need to be argued? No-one is suggesting it's not the case, and it seems rather self-evident.

2 hours ago, zokum said:

The distance doesn't matter.

Wether that was how Zokum wants it to be 'felt' or not, that's how it comes across.