I'm working on creating a simple but thorough framework for roguelikes so that I can prototype a few that I've had jumbling around in my head. It's a fairly ambitious project, so I'm working to abstract as many concepts as possible into a simple construction.
I typically design feedback first, with a central focus on UI. If there is no UI for a feature or it does not yield any feedback, then it really doesn't matter anyway. In this spirit, I've begun working on creating an abstraction of agent perception, which is used for modeling AI.
In this model, the agent is both a controlling intelligence and an entity in the environment. Percepts are the information that the entity can interpret, from which the agent may evaluate and select from its actuators how it will act with the environment. I'm trying to reverse engineer the logic in the real world into a sensible and easy to work with abstraction. Within the agent, we can break this down even further into Sensory Systems and Sensations. The Sensory Systems describe what and to what degree an agent can acquire raw data, or Sensations, from the environment.
The five human Sensory Systems:Vision - Sense of sight
Taction - Sense of touch
Audition - Sense of sound
Olfaction - Sense of smell
Gustation - Sense of taste
These Sensory Systems detect raw input for the following Sensations (in humans- other animals have different senses for different sensations),
Photoreception - Brightness and Color of light. (Vision)
Chemoception - Chemicals. (Olfaction, Gustation)
Nociception - Pain (All)
Electroreception - Electrical signals (All, not trusted by instinctual brain)
Mechanoreception - Physical interaction, including sound (Audition, Taction)
Thermoreception - Temperature (Taction)
Proprioception - Kinesthetic sense (Taction)
Equilibrioception - Balance (Audition)
Magnetoreception - Magnetic fields (Vision, not trusted by instinctual brain)
Chronorception - Time and circadian rhythms (All via Zeitgebers, mainly Vision via daylight)
Note: It's interesting that our pleasure from food is derived from the intersection of chemoception from our olfactory and gustatory systems-- If both the taste and the smell converge, we know that it is safe to eat, but if they diverge, it may not be and we find it unpleasant.
Is it important to distinguish Sensory Systems from Sensations? I think so, as we may want to utilize this abstraction layer for varying effects. In a simple game, we may just have a single Sensory System and a single Sensation (which is most roguelikes)- but we should be able to add and map as many as we want without problems. We also want the sensing abilities of each entity to vary in interesting ways- creating a distinction will allow us to input emissions/Sensations into the model and allow entity Sensory Systems to gather the data. We can create a mapping of Sensations to Sensory Systems- where the Sensory System describes an individual's ability to acquire Raw Data from the environment. For example, Photoreception has two basic properties- Brightness and Wavelength, which are typically defined via spectrum. Vision describes the range of brightness and wavelength that an entity can detect. We typically can't improve these Sensory Systems without artificial means, but we can improve our ability to evaluate these Sensations. Ultimately, we need to process these sensations before delivering them to the UI or AI for actuation. It then seems useful to abstract how these sensations are evaluated. I've come up with three basic super-modes.
Cognition - Conscious analysis of data.
Intuition - Subconscious inference of data.
Instinction - Unconscious mapping of data to evaluation.
While the quality of input can't be improved (except by artificial means), our processing of that data can be trained. It may not be important to have more than one evaluation mode for a game, but they help to rationalize certain elements of the game. One possible application may involve the perception of Ghosts. A ghost may provide little raw data to analyze or react to, but we may be able to intuit it regardless. Not by how strong our senses are, but by how sensitive we are to processing subtle influences. A few examples to emphasize the distinction:
Sympathy - Cognitive. We consciously rationalize how another person's state would feel (sensation reasoned within our imagination).
Empathy - Intuitive. We feel what another person's state actually is (sensation mapped to emotion).
Fear Sense - We can innately detect, on a continuum, how afraid a person is through a mapping from our sensory input. Doesn't provide information, just automatic reactions (sensation mapped to reaction)- chill down the spine, or a surge of hormones.
These concepts overlap in application, but different evaluations and weights may provide information that provides incentive to behave in a particular way. Since the player's avatar is the aspect of the player Agent that is acquiring information from the game world, it's also partially the Agent's job to interpret that data. From a UI point of view, providing the player with raw sensation data makes them responsible for interpreting the meaning. While this can be very interesting, we typically want the Agent's abilities, stats, skills, qualities, etc to provide the information. It could be a lot of fun to play a character that is manically afraid of all things, especially if the player doesn't know this. IE. Instead of a peaceful townsfolk, you suspect that they want to dismember you in a ritual sacrifice to their bloodthirsty deity-- okay, that may be TMI, but the avatar could fail to properly interpret their friendliness and trick the player into slaughtering them all. Evaluation includes misinformation-- which can be a lot of fun.
Another more sense-related example may be understanding why a sensation exists. The Aurora Borealis is the result of particle radiation (primarily from the sun) sneaking by the earth's magnetosphere and interacting with the atmosphere. Suppose our Avatar sees a flash of light- how is the avatar to evaluate that information for the player to make reasonable decisions from? The player will always be able to guess, but a well-designed game will not provide too great of an advantage to an experienced player (we don't want features to become arbitrary at different player skill levels). Is it a magical spell? Divine judgement? A flash of magnesium? Bright Light has meaning relative to that Avatar.
Telepathy could be rationalized without the addition of new senses or sensations, but as a property within an intuitive evaluation mode. IE- suppose that Telepathy is derived from Magnetoreception. The fields emitted by cognitive beings (higher wavelengths, or something) may have subtle effects on the ambient magnetic fields and, with enough training, we might be able to create an intuition about these subtle fluctuations- thereby inferring the presence of nearby entities. We may be able to develop a way to further evaluate this information to deduce what these entities are thinking. In many ways- cognition, intution, and instinction just describe different facets of the same ideas.
Creating meaningful evaluation modes really just depends upon how senses, sensations, and other factors are all mapped together. I probably wouldn't ever try to implement a realistic sensory model- but I thought the abstraction may be useful to others. There are some simple graphical techniques we can use to convey this data. 'X's are unknown, and any further letter/hue/saturation increases specificity. 'q'uadriped, 'd'og, 'p'ig, etc. Evaluation modes have much more to do with what emission patterns correspond to properties of creatures and objects-- that is, the evaluation modes are what tells us it's a humanoid or a goblin, friendly or hostile, dangerous or pathetic- etc.
To summarize:
Entities produce emissions, emissions are detected by sensory systems in the form of sensations, which are then rationalized by evaluation modes and presented to the UI or AI for decision making. Sensations that can't be completely rationalized are provided as raw data to the UI in a form that is relevant to that Sensory System (IE. if we hear something but don't know what it is, we might notify the map-- either as a direction, a specific location, or a general location-- maybe the type and intensity of the sound as well-- if we hear it over time, we may can filter the emissions to improve the specificity of the evaluations).
On the most mundane level, this is trivially implemented with singletons. Brogue's evaluation mode is total- anything you can detect you understand, but your Sensory Systems are limited to vision, clairvoyance, and telepathy. Your emission to the enemy is in the form of a heat map while their sensory system is described by their scent attribute. Stealth and dark places reduce your emission of heat (not formally heat, but an abstraction that describes your overall emission). You have perfect vision, apart from LOD in the form of light- so anything in your LOS/LOD you have perfect information about.
I imagine most any roguelike could be specified using this abstraction and done so in a manner that is both easy to implement, use by AI, and easy to communicate to the player.
