Glossary

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About

Contains descriptions of various S.T.A.L.K.E.R. related terms used in modding and in X-Ray Engine.

AI

Term	Definition
Offline	Simulation of life in any given radius from the player will be calculated by a simplified formula
Online	Simulating life within any given radius of the player will be completely calculated
A-Life	Simulates the life of the game world as an independent ecosystem
Anim Point	Key positions in which the animation should be played
Finite State Machine	Common and convenient technique for programming the behavior of bots (NPCs) in computer games.
Goal Oriented Action Planning	AI design technique in which a chain of behaviors of agents (NPCs, abstract entities, "living" obstacles) is automatically selected in real time to satisfy a goal.
Motivation Graph	Decision-making method described in AI Game Programming Wisdom 2, which, according to the authors, is something between Decision Trees and Neural Networks.
Graph Point	Monsters and stalkers in offline move on graph points
Gulag	Gulags control a set of stalkers together by assigning them each tasks by task priority. For example a gulag could contain tasks for patrolling an area and sitting at a campfire. The priority of these tasks will mean that the first stalker "caught" by the gulag (that is, the first stalker to be given over to the gulag's control) will patrol the area with subsequent caught stalkers simply sitting at a fire. A stalker is "caught" by a gulag be entering the associated "Smart Terrain".
AI Map	AI Map consisting of nodes
gvid (game_vertex_id)	Graph Point index
lvid (level_vertex_id)	Part of *.ai . AI Map node
Smart Cover	A system designed to control the behavior of NPCs when using cover.
Smart Terrain	Area which, when entered by a stalker, "captures" that stalker and assigns them tasks to perform. These tasks are allocated by the smart terrain's controlling Gulag.
Space Restrictor	An object that defines zones with special properties or restrictions in the game space.
Way Point	A predetermined point on the map that serves as a reference point for NPCs. Waypoints indicate their movement pattern or where they should go.
Info Portion	It is a piece of information that can be passed between characters, saved in quests, or used for AI decision making.

Animations

Term	Definition
*_hud animation	Animations for the *_hud object
Motion Mark	Time intervals in the animation in which something happens
Motion Reference	Reference to the animation library ( *.omf )

Coding

Term	Definition
Luabind	Luabind is a library that helps you create bindings between C++ and Lua. It has the ability to expose functions and classes, written in C++, to Lua. It will also supply the functionality to define classes in lua and let them derive from other lua classes or C++ classes. Lua classes can override virtual functions from their C++ base classes. It is written towards Lua 5.x, and does not work with Lua 4.
LuaJIT	LuaJIT is a Just-In-Time Compiler (JIT) for the Lua programming language. Anomaly uses LuaJIT 2.0.4

Compilers

Term	Definition
xrAI	AI Compiler
xrDO	Detail Object Compiler
xrLC	Level Compiler

Materials

Term	Definition
Game Material	Responsible for the physical feature of the surface (friction, damping & etc.).

Objects

Term	Definition
Dynamic Object	An object that uses bones
Multiply Usage Object	An object that creates an Imposter texture of the same object.
*_hud	*_hud is a model in front of the player in the hands of the character. Usually it is a model of a weapon, grenades, hands.
*_world	*_world is a model in-game world (NPC weapons, 3rd-person view). The difference from the *_hud model is that the *_world must have a collision to calculate the interaction with the game.
Static Object	Static object
Detail Object	Static object (grass, rocks, debris and other landscape details) with high optimization to display a large number of small objects without significant performance loss.
Scene Object	An object in the SDK that represents a reference object that uses a model to visualize and interact with the environment.
Light Source Object	Light source.
Sound Source Object	Sound source.
Sound Environment Object	Object with environmental sound effects.
Glow Object	Glow object.
Fog Volume Object	A object to simulate dynamic volumetric fog, smoke and other gaseous effects.
Sound Occluder Mesh	Geometry for calculating sound propagation.
Custom Data	Custom or additional parameters (in *.ltx format).
Hierarchical Occluder Mesh	Geometry defining the visibility of an object to remove from the renderer.

Joint Types

Term	Definition
Rigid	Joint type that completely restricts all transformations.
Cloth	Ball joint . Allows rotation in all directions, but without translation.
Joint	Universal joint. Automatically selects the optimal physical connection type based on constraint analysis (between Hinge and FullControl(partially constrained axes)).
Wheel	Hinge-2 joint. Allows rotation around the first axis (suspension axis) and rotation around the second axis (wheel axis).
Slider	Slider joint. Allows movement along one axis only.

Optimization

Term	Definition
Portal	A portal between the two sectors.
Sector	Sector is part of Portal Rendering. An area or section of virtual space that contains objects and geometry for rendering. Sectors help organize the scene, allowing you to control visibility and performance, especially in large worlds.
Hierarchical Occlusion Mapping	Technique in computer graphics that uses a multi-resolution representation of occlusion information to efficiently culling objects that are not visible.
Progressive Meshes	One of the methods of dynamic level of detail. Only for Dynamic Objects .

Shaders

Term	Definition
Compile Shader	Shader used by the Level Compiler. Specifies to the compiler the features of the final game level geometry. The source geometry, depending on the compiler shader, may have different features.
Engine Shader	Shader responsible for the visual appearance of the surface.

Particles

Term	Definition
Particle Effect	Single Particle Effect. Stored in *.pe files.
Particle Group	Particle Effects Group. Stored in *.pg files.