[BY ST.ALFONZO, FROM DOOMWORLD]>> Layout and Structure <<
Standard doors (or those which do not feature remarkable linedefs and/or which are assigned a typical door texture) are for the most part used scarcely in Doom. Doors which require keys, lead to secret areas or are activated by shootable switches or walkover lines are to be considered exceptions to this generalization as they typically do little to disrupt the fluidity of gameplay. Doors serve more toward area segregation and combat control than as aesthetic dividers, and are used to grant the player easier navigation and time to either prepare or contemplate before entering the next room. As is often the case, this somewhat liberal use of doors allows the mapper to create a contrast in design between rooms separated by doorways, lending to some interesting shifts both visually and in terms of gameplay.
Here’s a selection of maps from each episode that we may use to illustrate door use, as well as a general overview on how doors are used between episodes:Knee-deep in the Dead
Of the three episodes, Knee-deep in the Dead uses regular doors the least. Most areas are separated by shifts in height or direction, which differs greatly from the slightly more uniform layout of maps in The Shores of Hell, and to a lesser extent Inferno. However, there is still a great deal that may be learned from the study of door use in E1. E1M3, 4 and 7, for example, all place the player in a room isolated from the rest of the level by a standard door.
The first and only standard door (if we choose to exclude the exit for its being canon) allows the player to prepare before encountering the first monster in the game. It is expected that the player is still getting to grips with the controls of the game at this stage, and having a door here gives the player time to set his priorities and make the game move at his pace. Since M1 is a small and linear map, the function of the door could be seen as similar to those used in E3M1 for example, which is equally a one-way street. Doors cannot really obstruct the flow here as they are passed through only once (see M7 below for further examples).
E2M1, if we are to take the final M1 counterpart, is an also linear map which introduces teleporting to the player, and so the role of the door as a means of compartmentalizing and segregating areas is somewhat usurped, or at the very least expanded upon.
At the opposite end of the episode is E1M7, which interestingly features only 3 standard doors of 17 in being perhaps the second most sophisticated level in the episode after M6.
The use of all three keys and a considerable amount of backtracking makes the use of doors particularly interesting. The lowermost door indicated [O] leads off to an optional area of the map which is not reachable via any other means, while the centremost door indicated [F] similarly leads off to a segregated area, but one to which a visit is deemed necessary for the player to complete the level. With the first example we might accept that the player will be unlikely to return to the southwest part of the map, and so the use of a door helps familiarise the player with the area beyond it through compartmentalization. Similarly with the second example, the centremost regular door (which stays open), the player is unlikely to visit the northwest portion any more than once, the red key having been obtained. Between these two doors however and elsewhere in the level the player is quite likely to revisit areas more than just once for both access and explorative purposes. The rising pillar, for example, gives the player access to the flanking slime pits in which multiple secrets reside, while the overlook closer to door F surveys these accessible areas.
The topmost door indicated [.B], just as with M3 and 4, allows the player a moment of collection, as well as a chance for the music to intimidate the player!
The Shores of Hell
- Doors [E] and [I] are trap doors which are located in areas that see heavy traffic. Door [C] is an exception to this, as the player is likely to only pass by the one time, but critically, all three examples occur in somewhat unpredictable locations, rather than immediately behind the player following the collection of the yellow or red keys, for example.
- [L] is a rather interesting door that can probably be certified in being aesthetic rather than practical. Note the unique switch rather than door texture here.
- Door [J] is located within a trap location. The player is rewarded by exploring new facets of the level as they open up, however small.
- [P] is a remotely controlled door.
- As with all other maps in the episode bar the final one, door [Q] is the signature exit door leading to the “airlock” or “exit chamber”.
Doom’s second episode is where doors are first seen being used in drastically different ways, no doubt as a by-product of Petersen’s mapping style. Whereas Romero’s door deployment is more precise and controlling, Petersen’s is a great deal more haphazard, if not impossible to deduce. If you’re mapping for The Shores of Hell, you could probably get away with a great deal more in this department than you might in the first, and even in the third episode.
E2M5 & E2M6
These two maps, fortunately, have a very distinct procedure when it comes to door placement, in that they both feature very tightly framed doorways that branch off from a central passageway or area. The below diagram indicates, as before, the whereabouts of all the standard doors (those without remarkable linedefs and which are not secret related), but also the use of standard doors using a switch texture as indicated by the blue circle; a trend which is largely omitted in other maps of the game (E2M7, E3M3 and E3M5 sees some semblance of this style return, but it is here that the epitome resides!).
An astounding 35 doors in E2M5 sees the player drawing to a halt almost every couple of paces, and at first glance the whole setup can seem sort of chaotic. However, there is a great deal of order to the door arrangement here both stylistically and with relation to gameplay.
You will notice that a few of the doors lead to areas that, unlike E1M7, are not accessible only from one direction. Indeed, there are still many that do (such as with [M], [J], [Q], [A2] and [F2]), but there is a great deal of connectivity here, regardless of most entrance and exit points being located just feet from one another. Doors [A] and [G], [V] and [W], and [X] and [Y] all lead to looped pathways/areas, giving a stronger sense of perceived non-linearity, and many others such as [I] and [R] or [H2] and [I2] are linked via distinct, feature filled areas. A key thing to take note of here is that even the passageways are detailed. In addition, many of the blue circled doors (those which have a switch texture) branch off from hub-like areas.
With regards to gameplay, it is plausible to suggest that the doorways were used as a means to encourage the player to go exploring. While vast tracts of secret area are stowed away in the northwest of the map in a place which is everything but compartmentalized, there’s a great deal of goodies stashed behind closed doors.
- Door [T] is less so a door than it is a lengthy passageway that functions as a door in its entirety. Though the placement of the door-passage itself is purposed with hiding a secret area, the effect that is created might be considered wholly aesthetic.
- Doors [Z] and [A2] are placed symmetrically opposite each other, but [A2] leads to an area of questionable significance. In this case, the map’s symmetry takes priority over any indication of where to go, and is further indication that the doors here serve solely to compartmentalize rather than control combat.
For the most part, the use of doors as presented in E2 is replicated here, but a decrease in orthogonal design and an increase in abstract shaping sees substantially less intricate compartmentalizing of the sort seen in E2M5 and conversely more focus on the aesthetic - though not obstructive - and the experimental. Those who are mapping for E3 should seek to consolidate the flow retention seen in E1 with the more abstract or even gimmicky qualities of E3 maps such as Limbo’s gate system, Cathedral’s patterned layout, or Slough of Despair’s severed hand...
As was mentioned with E1M1, E3M1 is a linear map that employs a many doors of which are passed under only once. There’s not an awful lot to say about this one except that it affirms an increase in standard door permissibility where linearity is descriptive of level progression.
Unholy Cathedral has a monumental 38 doors in total, but pulls of the impressive feat of not having a single one of these standard doors interfere with the flow of gameplay. This is because they are not at all spread out, unlike in E2M5 or 6 for example, and are in fact grouped strictly with regards to map layout. Each group of four, central doorways links the corners of the map to the centre, and the player is able to deduce extremely quickly because of the remarkable structure of the map just where all the doors will lead, and how to navigate from one corner of the map to the other. In an instant, almost all of the doors in the map are less an obstruction and more an indicator of where to go. It is the perfect example of how best to combine symmetry with door usage while still giving the impression of having ample space to run around in and a clear sense of location and baring.
Also important to note are the first 4 doors in the map which allude to the maps structure and means of progression before the player has even made a move. After passing through one doorway and observing the way in which the map curls around the centre, the player, just as before, is able to develop an idea of where those other doors might lead.
- Secret doors [A] and [F2] are marked not by any offset, but by their positioning between two symbols. This is an interesting design motif that is usually unseen in other wads, where it is preferable to have decorations, lighting or texture variation give away a secret location.
- Doors are substituted twice in this map for another unique design motif involving the simultaneous raising and lowering of interlocking bars to allow passage. Both examples (in the north and northwest areas) lead to areas of the map that are somewhat distinct from the rooms adjacent to them.
***>> Summary <<
- Regular doors are used sparingly in general, though even less so in episode 1.
- Regular doors are used less in areas that see a lot of heavy traffic, where other design motifs such as height and direction are used to separate areas and retain flow.
- They are mostly used as area dividers and for combat control rather than for aesthetic purposes, although in Petersen's case the two can be made to cooperate under a highly stylized motif.
- Irregular doors (secret doors; key doors etc) are exempt from following any strict rule set, and may be used freely as long as they adhere to strong connectivity.
- Petersen loves using doors to compartmentalize areas both central and extraneous to map progression.