DOOM SnapMap - Halls of the Inferno
Gameplay Video
Overview
Halls of the Inferno is my first foray into the DOOM SnapMap editor. With my primary focuses being on growing my skills related to level flow and engaging combat encounters, I deferred some narrative details to an AI writing tool. The total development time was approximately 80-90 hours. The level can be played using the SnapMap code KH9QQKJR.
I designed and executed the layout of level modules in SnapMap to realize the flow of the level vision.
Provided additional level design to empty modules using DOOM art and FX assets.
Scripted all gameplay, objectives, and interactions.
Designed, tested, and iterated custom combat encounters of varying difficulty using basic spawning tools.and logic
Populated the level with resources and loot
Used the provided selection of DOOM art and FX assets to facilitate the level narrative and gameplay flow.
Development Process:
Documentation
Level Building
Gameplay
Pickups
Combat
Development
Documentation
After completing some of the basic SnapMap tutorials and doing my own research, I used an AI writing tool to produce and refine a narrative base for the level. I started with a very broad and generic result and cut back on story beats to reduce the amount of feasible gameplay content. In my research I’d learned that one of SnapMap’s creative bottlenecks is the memory limitation, and planned the gameplay accordingly to accommodate for enough logic overhead. My primary goals that I set and achieved for using an AI writing assistant were:
Create a narrative context to build a level with.
Produce diegetic objective descriptions for specific gameplay behaviors such as object collection, environment interaction, and other types of gameplay.
Combine the narrative context with the gameplay objectives into an effective, cohesive game description.
Once I had a result I liked, I built a level design document around the primary objectives I’d created and the narrative descriptions for them.
Navigation objective - There would be an environmental maze for the player to navigate through.
Interaction/Combat objective - There would be a series of player interactions that trigger increasingly difficult combat encounters.
I decided not to have more than 2 primary objectives so that I could keep the map scale to a minimum while still being able to create effective gameplay to provide a fuller experience. The document was updated regularly while I worked on development in SnapMap.
Level Building
Given the memory limitations of SnapMap, I decided to block out the level layout directly in the editor, using the room shapes and connectors as a guide. First, I formed the looping section that serves as the introduction to the level and combat, as well as the first main objective. I used this area to help establish a baseline of the gameplay needs.
Since the majority of combat rooms in the first half of the level would consist of junctions, featuring 3 or 4 other module connections, barren, I opted to add my own props to enhance and differentiate the spaces. The use of additional geometry opened up more possibilities for interesting combat since the micro-scale level design in SnapMap is naturally limited when making larger maps with so many moving pieces.
During the second half of the level, I used more advanced room modules to allow for larger combat encounters. To determine which modules I would use, I considered factors such as:
The level of difficulty I expected the combat to be in the room
What combinations of enemy types I planned on using at any given time
The overall architecture of the prebuild and the spatial emotions they influenced (Constrained vs. open)
An example is the last objective, to destroy 3 gore nests after the player receives the Super Shotgun. During the first 2 encounters, I encourage the use of the new weapon by using a room with tight lanes in addition to spawning tough enemies that attack at short range. The very last room was specifically chosen for its circular flow and open design. The central element in the last room also serves as a natural POI location for the environmental storytelling props and FX that I added.
Event Scripting
All of the events in the level are grouped together as clusters of logic nodes. The spatial nature and memory usage of the logic scripting in SnapMap forced me to optimize wherever possible. As one of my primary focuses, I strove to create a smooth and cohesive gameplay experience through several player feedback mediums, including:
Objectives and sub-objectives
Waypoints and POI markers
Comfortable resource distribution
Smooth combat ramping
Custom-made checkpoint system
Forced forward progression by locking previous areas
The majority of progression events are structured around combat encounters. The most common methods I used to drive these events are interactables and new weapon pickups. Pairing these player actions with custom-defined POI markers allows me to keep the gameplay moving forward with minimal player confusion.
Pickups
Since AI glory kills don’t grant health points in SnapMap, I chose to design a more traditional DOOM experience by populating the level itself with all of the ammo, health, and armor the player would need. I approached the distribution of resources through a loose, 3-step process:
The first step was making sure I at least had some pickups for health, armor, and ammo for the weapons the player would have at that point in the level. The health and armor pickup size as well as the number of ammo drops is scaled to match the level progression and combat ramping.
Through many, many playtests while developing the combat, I refined each section’s drops and distribution to match the combat pacing. Resources are strategically placed in rooms to complement the pacing, ensuring the player’s needs are met in both active combat zones as well as during lulls in the fighting.
Since the level is split into 4 primary areas with 3 possible player spawn points, each of these areas were mostly developed under perfect player conditions at each spawn. The last step for each area involved playtests starting from the very beginning of the level. This made sure that in each checkpoint section, I was able to gain realistic feedback on player states and resource needs during play.
Combat
In order to further improve my design skills, I built every combat encounter by hand. Using a combination of single demon spawns, pre-made demon groups, and custom demon groups, I was able to fully tailor the combat experience to the level layout I was creating. Encounters were structured using series of completion triggers, completion percentage triggers, and counters to stagger and pace the combat. Every encounter was heavily tested for tuning difficulty and resources. Some factors considered during encounter building and enemy choices included:
Overall level pacing for new enemy introductions.
The level design of the room or area for spawning ranged vs. melee enemies.
The player’s current weapon selection.
My goal to emulate a DOOM-style level led to much more combat than I initially imagined. Much of the level sees the player revisiting room modules, which required careful consideration to maintaining a fast-paced level.
