Glossary

This is a glossary of terms used when editing SRB2. For more detailed information about any term, click the link to the full Wiki article.

3D Block

* 3D Block is another term for FOFs.

Action

* Actions determines what Objects do during a given State. They are responsible for all interaction between the player and Objects.

Actor

* The actor is an Object that performs an action.

Control Linedef

* Control Linedefs are linedefs on a control sector. They tell the game what should be done to the tagged target sectors.

Control Sector

* Control Sectors are sectors outside the main map that are given a special function that change how things work inside the map. They are used to make things such as FOFs or linedef executors.

Cutscene

* Cutscenes are an arrangement of pictures and text that explain a part of a storyline in SRB2. Example of a cutscene would be the one that plays at the beginning of the game or the credits.

F_SKY1

* F_SKY1 is a special flat that displays a sky, instead of a typical floor or ceiling. The level header sets what sky is used for a level.

Flag

* A Flag usually refers to the properties of an Object. It is a also a term used in mapping, where it refers to the properties of linedefs or Things. Both are provided in the form of checkboxes.

Flat

* Flats are pictures which are used on either the ceiling or the floor of a sector.

FOF

* Floor Over Floors, or FOFs are floating platforms inside levels that are rarely called by their formal name, 3D Block. Different kinds of FOFs have different effects, like the ability to cast a shadow below them.

Fracunit

* Fracunit is a unit of distance measurement used in SRB2. In SOCs, a measurement of 1/65536 fracunits is usually used to allow for more accurate Object sizes. The term FRACUNIT with all-capitalized letters therefore usually tells you to multiply something with 65536. For example, an Object size of "2*FRACUNIT" means two fracunits, or a size of 2*65536 = 131072.

Freeslot

* A freeslot is an empty slot for Objects, States, Sprites and Sounds. They can be used to create custom entries without overwriting used ones.

IWAD

* IWAD, short for "Internal WAD", is SRB2's main WAD file. In current builds, its filename is srb2.srb, and it mainly contains SRB2's graphics, among other things. For technical reasons, some of the main data, like the maps, is included in separate PWADs, which are loaded at startup.

Linedef

* Linedefs are lines inside a level. These lines, when put together, make up sectors. They also hold texture information for SRB2, so that the game knows what kind of walls to draw.

Linedef Executor

* Linedef Executors are linedefs that trigger an event inside the map once another event has occurred.

Level Header

* Level Headers are text data — technically a SOC — that describes certain properties of a level such as its name, its sky, and the background music.

Lump

* Lumps are chunks of data in a WAD. Each lump has a name which identifies it, so that the game can load it and use it for its intended purpose. A lump might contain a sprite, a texture, part of a map's data, a SOC, or a variety of other things.

Lump Editor

* Lump Editors are programs made for manipulating WADs at the lump level. These are useful for creating characters and for low-level operations. Lump editors are not for creating maps. Examples of lump editors include SLADE and XWE.

MAINCFG

* The MAINCFG is a SOC lump that contains all kinds of settings for a WAD file, such as unlockables, level headers or custom Objects.

Map

* Maps are SRB2 levels. Maps are made up of sectors, linedefs, sidedefs, vertices, and things, which together describe the level's layout.

Map Editor

* Map Editors are programs for designing maps. Examples include Doom Builder, SRB2 Doom Builder, and SRB2 Workbench.

Node

*A node is a data structure in a map that is created by a nodebuilder for rendering purposes.

Object

* Objects are in-game items that can be modified or created with a SOC, such as enemies, power-ups or scenery items. Their behavior is defined in States, while their properties are determined through flags.

Palette

* The Palette is the set of 256 colors SRB2 uses. All graphics used in the game are restricted to these colors.

Patch

* A patch is a form of the Doom engine's picture format, used as data in textures.

PolyObject

* PolyObjects, are sectors that can move in all directions and rotate. They cannot render flats, however.

PWAD

* PWADs, short for "Patch WAD", are WADs that contains data supplementary to the main IWAD. For instance, WADs created in order to provide addons for SRB2 — levels, characters, etc. — are always PWADs. Many of the files that come with SRB2 are PWADs, such as zones.dta or sonic.plr.

Reject

* The Reject table is a resource added to levels that calculates if enemies can see the player or not.

Script

* A Script is a text file containing console commands. This can be useful for creating interactive events like dialogs, among other things.

Sector

* Sectors are closed areas of a level, made up of linedefs. Sectors also store how high the ceiling and floor of an area are, and what they look like.

Segment

*A segment, also called seg, is a section of a linedef that is created by a nodebuilder for rendering purposes.

Sidedef

* Sidedefs are the individual sides of a linedef. Since linedefs can have one or two sides; these are important, as they help the game determine what side of a linedef belongs to what sector.

Skin

* Skins are playable characters. Skins consist of very many sprites and a SOC describing the character's abilities. SRB2 comes with skins for Sonic, Tails, and Knuckles.

SOC

* SOC stands for Sonic Object Configuration. SOCs are text data used to customize a wide range of SRB2's features, including Objects, skins, the MAINCFG, and level headers.

Sound

* Sounds are the sound effects that can be played back by Objects when certain events happen.

Sprite

* Sprites are pictures that are made out of pixels. They are used to display Objects such as enemies, power-ups or scenery items. Compare with flats and textures which are used for the surroundings of a level.

State

* States define what actions and Sprites an Object uses for a given amount of time, i.e. what they do and how they look. States are usually combined into sequences that are called when certain events happen.

Sub-sector

*A sub-sector is a section of a sector that is created by a nodebuilder for rendering purposes.

Tag

* Tags are a method of applying special effects to the level such as FOFs or Linedef Executors. Linedefs are tagged to respective sectors.

Target

* The target is an Object that an actor performs an action related to, if applicable. For example, with shooting actions, the target will be the Object that is shot. With relative movement actions, this will be the Object the actor moves related to. The action is only performed as long as the actor can see the target.

Target Sector

* Target Sectors are sectors in a level that have control sectors with a linedef special tagged to them.

Tic

* Tic is a unit of time meaurement used in SRB2, which is equal to 1/35th of a second. In SOCs, a measurement of 1/35 seconds is usually used to allow for more accurate State durations. The term TICRATE with all-capitalized letters therefore usually tells you to multiply something with 35. For example, a State duration of "2*TICRATE" means two seconds, or a duration of 2*35 = 70 tics.

Tracer

* The tracer is an Object that an actor performs an action related to, if applicable. Unlike the target, the actor doesn't need to see the tracer to perform the action.

Trigger Linedef

* Trigger Linedefs determine the event that causes an effect to begin executing in a linedef executor. The kinds of events are whether the action occurs one time only or repeatedly, whether all the players or only one must enter the trigger sector, etc.

Trigger Sector

* Trigger Sectors are sectors which cause a linedef executor to activate when a certain event occurs inside them, such as a player or a gargoyle entering it.

Texture

* Textures refer to the pictures found on the walls of sectors. They are not images themselves, but rather an organization of different patches.

Thing

* Things are items that can be placed inside a map. Most Objects, like enemies, scenery or Rings, are also Things. However, some Objects can't be placed directly on a map, like projectiles, and are therefore not Things.

Thok Barrier

* Thok barriers are sectors of the height 0 that are used to define the level boundaries. They are needed to prevent Sonic from thokking outside of the level. They also allow Knuckles to climb correctly on the outer walls of a level.

Vertex

* Vertices (the plural of "vertex") are the endpoints of linedefs.

WAD

* WADs are SRB2's data-file format. They are made up of lumps.

WAD Editor

* WAD Editors are programs made for manipulating WADs. These include lump editors, which are used to organize the data, and map editors, which are used to design maps.