Mod Tester's Handbook tutorial - Crispy

Writing a Bug Report: QA terminology

A list of terms used frequently in development and testing

AI (a.k.a. Artificial Intelligence)
A set of behavioural responses programmed into computer-controlled characters and enemies designed to challenge and further immerse the player. Most AI is handled in the game code, but in some single-player or co-operative games, more tightly scripted elements like pathfinding can be put together in a level editor and fall under the responsibility of the game or level designer.

Alpha (channel)
A part of the texture that defines its area as being transparent or translucent in the game. Colours uncommon in most environments are used to designate the areas for Alpha removal, such as pure blue, magenta or bright green. If an Alpha is not functioning correctly for a game texture, one of the aforementioned colours may be visible.

Alpha (version)
An incredibly early build of the game that has enough there to boot up, but lacking many features. A working blueprint of the game that gives some idea of structure and layout. Many features will be unimplemented at this stage; expect crashes, hangs and soft locks due to missing/non-functional files, basic or placeholder artwork and rough audio.

Beta
The stage at which a game is feature and content complete and in a playable state. In theory the game can be tested from start to finish (perhaps by use of some debug commands to circumnavigate known issues). It is by no means bug-free, but most major issues should have been addressed.

Blocker
Any bug that prevents the user from progressing in the game. Blockers are absolute, i.e. if the level or game can be restarted or absolutely anything can be done (no matter how unintuitive or out of character) to bypass a critical issue, the issue in question is not a blocker. In short, blockers prevent full testing of the game and receive a very high fix priority.

Brush
In level editors that use Binary Space Partitioning (or BSP) such as the Half-Life 2 engine, any three-dimensional solid that is not an 'entity' or a model. Most of the major geometry in a level of this type -such as the ground, walls, ceilings, etc.- will be made out of brushes.

BSoD (a.k.a. Blue Screen of Death)
An acronym to describe a crash resulting in a blue screen with an error message or a call stack. Not just limited to PCs; BSoDs can occur on most consoles.

Build
A fully-compiled version of the game. Any time a change is made to the game files and the change is committed to the master game files, the game's build number increases by 1. With an SVN system your mod will likely run into thousands of builds before completion, since every minor change can be committed to the master files with ease. If you have a single member mastering your builds manually, they will probably only compile a new build when needed.

C2D / C2W (Crash to Desktop/Windows)
An acronym used to describe when a game closes itself abruptly and returns the user to the desktop environment of their computer.

Call stack
For the purposes of simplification (please correct me if I'm wrong), a list of a program's subroutines in operation at the time of a crash. Essentially a more detailed error message, a call stack appears on-screen as an alternative to a dump file or basic error message.

Clip
A term used commonly in testing to describe when a player avatar or object passes through an object. The term is through to be derived from id Software's 'noclip' debug mode, that removed player collision detection from the game. In games development, the term clipping actually means something entirely different.

CNR (cannot reproduce)
When regressing a bug, what the QA Lead would write in the bug notes if any of a bug's repro steps cannot be performed because of another bug. It is good practise to also cite the bug(s) preventing regression. A developer may also write this in a bug if they cannot reproduce the issue on their system.

CNT (cannot test)
The acronym used on a checklist or testplan to show that a check cannot be performed because of another bug or because a feature has not been implemented. It is good practise to also cite the bug(s) preventing this check.

Collision detection
The code that prevents two objects from intersecting with eachother. In 3D games, collision between models is handled by a 'bounding box' that may or may not be identical to the visible boundaries of the model. Similarly, in level design, artificial 'invisible walls' may be added to prevent the player from exiting the playable area of the game world. In 2D games this may be handled by 'sorting' (see depth sorting).

Console
A drop-down text input menu some games use to perform debug (and in-game) operations.

Crash
When a game closes itself abruptly. After a crash the user may be taken to a 'dump' screen or a screen with an error message or error code. Following this, the system should reboot itself automatically.

Critical path
A term used to describe the main, often necessary, route through a game. This can extend to unlockable upgrades, major paths through a level or conversation strings with key characters. It does not refer to optional extras such as bonus levels, non-essential upgrades and incidental dialogue. The closer a bug is to the 'critical path', the more likely the end-user is to find it and the bigger its fix priority.

Debug
A mode or set of commands that allows a developer or tester to perform operations that either have not been fully implemented or cannot normally be performed within the rules of the game. Examples of this include cheats like 'god' mode, 'noclip/fly' mode, 'notarget/invisible' mode, as well as modes that help artists assess their work, such as 'wireframe' mode. Any bug found when using debug mode should be re-attempted without the use of debug to ensure its validity before a bug report is entered into the bug database.

Depth sorting
A method of creating the illusion of a third dimension for 2D games. When two 2D objects occupy the same 2D co-ordinates, based on the values of these objects, depth sorting will determine which object appears to pass under the other. If a character in a top-down 2D game appears to pass over or inside of a tree, this would be a depth sorting bug.

Diffuse map
The essential layer of a texture that defines the combinations and arrangements of colours on a surface. The diffuse map makes a flat surface look like a brown door made out of wood, for example. Any other maps are simply accentuating and improving on this effect.

Draw distance
Draw distance is the distance within which objects in the world are drawn. Objects beyond this distance are 'culled' (not drawn) and will only be drawn as the player avatar approaches them. If the draw distance in a game is set too close to the player, objects will 'pop-up' suddenly, breaking the immersiveness of the gameplay.

Dump
The process that occurs after a crash whereby game data relating to the crash is recorded into a 'dump file'. Programmers can look at these dump files and attempt to work out which part of the game produced the error.

Entity
In some level editors (including Half-Life 2), entities are special additions to a level that control various properties relating to the world, the player and all other objects within the world. Entities are usually invisible, but can be assigned to brushes (as brush-based entities). For instance, (in Half-Life games) a rope down a cliffside can only be climbed once a 'func_ladder' has been placed beside it. Without the entity allowing a player to climb, the rope is just a non-interactive piece of scenery. Entities control most 'special' rules in a game (such as scripted sequences, physics puzzles, fogging, breakable scenery, etc.) and even some basic rules (such as light sources, transparent glass and doors).

Environment art
Any level art not created in level editing software. Generally speaking, any separate model placed inside a level to increase the level of detail. Usable weapons, character models, vehicles and structures are not considered environment art.

Exhaustive playthrough
An extensive playthrough of a single-player or co-operative game undertaken by a tester whose focus is to experience every aspect of the game. This includes: completing every level/mission/quest, talking to every character, collecting every item, unlocking every upgrade, etc.

Fogging
Fogging is often used in conjunction with draw distance. A maximum and minimum density for the fog in a level is set and these values both correspond to distances from the player avatar. Objects moving between the minimum and maximum fog densities will appear to fade in and out of the fog. This is a much smoother visual technique than just having objects pop-up in the distance.

Geometry
A useful term to describe large areas of 3D level art in abstract forms, such as cliffs and caves. E.g. "Missing/untextured face in cliff geometry".

Hang
If the game ceases to respond to user input (i.e. it freezes) this is called a hang. A hang is different to a crash because a hang usually requires the user to manually reboot the game or the system.

Hard Lock
Any hang or crash that requires the user to reboot both the hardware and the game to resume control of the game. All hard locks are class A issues.

HoM (Hall of Mirrors)
In some engines, the visual effect seen when viewing the face of an object with no texture assigned to it. This effect can be seen most clearly if falling out of the level.

Lag (note: not the same as latency)
While latency is, generally speaking, the measured or demonstrable time taken for data to be sent, received and retrieved, 'lag' is a term used to express a noticable and unacceptable delay between a user's input and their resulting actions in-game. Lag can be attributed to too much client-side traffic, too much server-side traffic or -less likely- game/engine code.

LOD (Level of Detail)
The name given to the optimisation technique of swapping in higher-detail versions of models as the player approaches them in the game world. If done correctly, this changeover appears to happen seamlessly because the model usually switches to a lower or higher detail version at a distance where the player cannot discern any difference between the two.

Loser playthrough
A playthrough of a single-player or co-operative game undertaken by a tester to ensure that failure in the game functions correctly on all levels. This includes: dying to every enemy, failing every level/mission/quest in every conceivable way, attempting purchases/transactions without an adequate stock of money/points/items, manually quitting levels via the menu, etc.

Milestones
For modders, milestones are targets for the team to hit that help plan out the mod's development timeline and motivate team members. If realistically achievable and communicated well to the team, milestones can have a very positive effect on productiveness and momentum. Bugs fixes can be scheduled for specific milestones to help with individual task management and development planning.

NAB (not a bug)
The comment you're likely to see if a developer decides that a perceived bug is actually an intended part of the design. Synonymous with 'as designed'.

NMI (need more info)
The comment you're likely to find if one of your bugs is sent back to you by a dev or QA Lead for more info. Be more specific, write clearer repro steps, whatever it takes for a developer to be able to understand and fix your bug.

Normal map
A layer within a game texture that provides extra information for shading a flat surface. Normal maps make a flat surface appear more bumpy and allow them to respond to light sources with more detail. On models, normal maps are usually derived from a higher detail version of the same model.

Poly (a.k.a. Polygon)
Any single face of a model. A high-poly model is a very detailed model with many different faces, used for models close to the player; the opposite being true of a low-poly model. In the term 'polycount', this word usually refers to triangles (or 'tris'), since when game engines analyse model topography all faces are broken down into triangles as their mathematical properties can be easily evaluated in calculations.

Portal
The ambiguous term some people use to describe a hole in a level's geometry that allows the player to view out of the world. In games development terminology, portal actually means an entirely different thing.

RC (a.k.a. Release Candidate)
The stage at which a game is thought to be ready for a major public release. The game should be feature-complete (as far as features planned for this specific release) and free of major bugs (i.e. all A classes and most if not all B classes). It should be playable without the use of any debug commands (if a multiplayer, any cheats should already have been removed - Hi Valve!). You can have a release candidate for any public version of the game, e.g. you could have a Beta 4.0 RC1 (the first effort at a version of Beta 4.0 for public release) or a v2.0 RC4 (the 4th attempt at a version 2.0 of the game for public release).

Regression
When a developer attempts to fix a bug, the fix must then be checked by a third party (usually a tester). This process is called regression, and is there to ensure that a) the bug is actually fixed in this build, and b) the fix has not created any additional bugs or exploits.

Roadrunner playthrough
A playthrough of a single-player or co-operative game undertaken by a tester to ensure basic functionality throughout and that the game is completable from start to finish. Roadrunners do the bare minimum to progress within the game in the fastest possible time, including avoiding enemies, taking shortcuts, skipping cutscenes and dialogue, even failing scripted sequences or deliberately dying if it saves time.

Soft Lock
If the user cannot freely control their character (i.e. they are stuck or cannot return to the game area) but can still access the game menus, this is known as a soft lock. Soft locks require the user to restart the level or the title to resume control of the game. The majority of soft locks are class A issues.

Specular map
The layer of a texture that defines the reflectivity of a surface to create a mirror effect.

Texture (or texture map)
A 2D image stretched across a single or multiple surfaces in the game world. Figuratively speaking, the 'paint' applied to any surface in the game to give the resulting visual effect. In more modern 3D games, multiple layers of textures are combined on a single flat surface to give the impression of reflectivity, transparency or 'bumpiness'. These layers each do different things and have different names: see Alpha, Diffuse, Normal, Specular.