oblivion-dialog-system

name

oblivion-dialog-system

description

Pure reference for how Oblivion's (TES4) dialogue, voice, and quest systems work — every record type (DIAL, INFO, QUST, IDLE, PACK), its binary layout, field meanings, enums, the condition (CTDA) system, the topic-type and add-topic model, result scripts, and a checklist of everything required for dialogue to fire in-engine. Use when authoring, reading, or debugging Oblivion dialogue/quest/voice records, when reasoning about how a topic reaches an NPC, or when you need the exact structure of any of these records. This is a description of vanilla Oblivion only — it contains no conversion/import logic.

Oblivion Dialogue, Voice & Quest System

This skill is a pure reference for how vanilla Oblivion (TES4) routes dialogue. It describes only how the game itself works — it deliberately contains no conversion or import logic.

It is built from two authoritative, grounded sources in this repo:

1. xEdit Core record definitions — references/xEdit/Core/wbDefinitionsTES4.pas (and shared pieces in wbDefinitionsCommon.pas): the binary layout of every record; verbatim field names/sizes/enums.
2. Real Oblivion.esm data — export/Oblivion.esm/ (a pure KEY=VALUE dump of the actual master file, one file per record type), giving real field values.

When the answer needs an exact byte layout or full enum, open the matching reference file rather than guessing:

• references/records.md — every record's complete subrecord-by-subrecord layout, field types, sizes, and full enums (DIAL, INFO, QUST, IDLE, PACK).
• references/conditions.md — the CTDA condition system: 24-byte layout, operator/flag byte, OR-chaining, the parameter-type table, and the function indices that matter for dialogue (GetIsID, GetStage, GetQuestRunning…).
• references/checklist.md — the full "everything that must be true for a line to fire" checklist, plus common failure modes and their fixes.

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The mental model (read this first)

Oblivion dialogue grew out of Morrowind's text-based system. It is a filtered, priority-ordered query over INFO records, with two ideas that shape everything:

1. Topics are global objects, not branches. A DIAL (topic) is a named bucket of INFOs. The same topic can be shared by many NPCs and many quests.
2. The AddTopic mechanic gates visibility. A topic only appears in an NPC's list once it has been "added" — usually by a script command (AddTopic) or by an INFO's Add-Topics list (the NAME subrecord). Conditions then filter which INFO under that topic actually plays. AddTopic visibility is the central mechanic of Oblivion dialogue.

When an actor needs something to say, the engine looks at the topics available to that actor, and for each it picks the first INFO whose conditions all pass, in quest-priority order.

The record hierarchy

QUST (Quest)        owns dialogue via topic association (DIAL.QSTI). Holds a
 │                  priority, flags, stages (journal + result scripts), targets,
 │                  conditions, and an attached SCPT script (SCRI).
 │
 ├── DIAL (Topic)   a named bucket of INFOs with a Type (Topic / Conversation /
 │    │             Combat / Persuasion / Detection / Service / Misc). Lists the
 │    │             quest(s) it's associated with (QSTI) and its display text
 │    │             (FULL). The INFOs live in the topic's GRUP.
 │    │
 │    └── INFO      ONE spoken exchange: a Type + NextSpeaker + Flags (DATA),
 │                  the owning quest (QSTI), one or more Responses (voiced text
 │                  with an emotion), the conditions (CTDAs) that gate it,
 │                  Choices (TCLT) that branch to follow-up topics, Add-Topics
 │                  (NAME) that reveal new topics, Link-From (TCLF/PNAM) wiring,
 │                  and an optional result script (SCHR/SCDA/SCTX/SCRO).

IDLE (Idle Animation)  a .kf animation gated by conditions; chained via DATA
                       (idle parent / previous). Played during AI and dialogue.

PACK (AI Package)      what an NPC does when not in dialogue (Find/Follow/Eat/
                       Sleep/Wander/Travel/…). Gated by conditions; can offer
                       services. Drives where/when an NPC is available to talk.

Voice in Oblivion

Oblivion has no Voice Type record. Voice assignment is implicit: each NPC has a race and gender, and the voice files for a spoken line are stored by race+gender under Sound\Voice\<plugin>\<Race>\<Gender>\<dialogFID>_<infoFID>.mp3. There is no voice-type record and no voice-type condition — the engine resolves the audio file from the speaking NPC's race+gender and the INFO's FormID.

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What must be true for a line to actually fire

(Full version with fixes in references/checklist.md. The essentials:)

1. The topic is available to the NPC — it has been added (via AddTopic script, or an INFO's Add-Topics NAME list, or it is an always-available greeting/service topic).
2. The owning quest is enabled/running if the dialogue is quest-gated. Quest-associated topics are implicitly gated by their quest (QSTI).
3. The INFO's conditions all pass — e.g. GetIsID(npc) to bind a line to a specific NPC, GetStage/GetQuestRunning to gate by quest progress.
4. The INFO has at least one Response (TRDT + NAM1) with response text.
5. Voice audio exists at Sound\Voice\<plugin>\<Race>\<Gender>\<dialogFID>_<infoFID>.mp3, or the line plays with subtitle only / silently.

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Quick subrecord cheat-sheet

Exact bytes, enums, and edge cases are in references/records.md. This table is for fast recall only.

Record	Key subrecords (in order)	Notes
DIAL	EDID, QSTI, QSTR, FULL, DATA(U8 Type), INOM, INOA	DATA.Type: 0 Topic, 1 Conversation, 2 Combat, 3 Persuasion, 4 Detection, 5 Service, 6 Misc. INOM/INOA = INFO ordering (internal).
INFO	DATA(3B: Type/NextSpeaker/Flags), QSTI(→QUST), TPIC(→DIAL), PNAM(prev INFO), NAME[](add topics), Responses[(TRDT 12B + NAM1 + NAM2)], CTDAs, TCLT, TCLF[](link from), result script (SCHR/SCDA/SCTX/SCRO)	No keyword/voice-type system. NextSpeaker enum: 0 Target, 1 Self, 2 Either.
QUST	EDID, SCRI(→SCPT), FULL, ICON, DATA(2B: Flags/Priority), CTDAs, Stages[INDX + log entries(QSDT/CTDAs/CNAM/result script)], Targets[QSTA + CTDAs]	DATA.Flags: 0x01 Start game enabled, 0x04 Allow repeated conversation topics, 0x08 Allow repeated stages.
IDLE	EDID, Model(MODL/MODB/MODT), CTDAs, ANAM(anim group section U8), DATA(related idle: parent + previous sibling FormIDs)	A .kf animation gated by conditions.
PACK	EDID, PKDT(general: flags+type), PLDT(location), PSDT(schedule), PTDT(target), CTDAs	Type enum: 0 Find, 1 Follow, 2 Escort, 3 Eat, 4 Sleep, 5 Wander, 6 Travel, 7 Accompany, 8 Use item at, 9 Ambush, 10 Flee, 11 Cast magic.

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CTDA conditions (the gate)

Every TES4 condition is exactly 24 bytes. Critical offsets (full detail and the parameter-type table in references/conditions.md):

• byte[0] = operator + flags. Bit 0 (0x01) = OR with the next condition; bit 1 (0x02) = Run on target; bit 2 (0x04) = Use Global.
• bytes[4:8] = comparison value (float, or a GLOB FormID if Use Global). 1.0 = 00 00 80 3F.
• bytes[8:10] = function index (U16 LE); bytes[10:12] unused.
• bytes[12:16] = param1, bytes[16:20] = param2.
• bytes[20:24] = unused.

Function indices you will see constantly in dialogue (decimal / hex):

Func	Name	Use
72 / 0x48	GetIsID	Restrict a line to a specific NPC/base object.
58 / 0x3A	GetStage	Gate by quest stage (param2 is the stage).
59 / 0x3B	GetStageDone	Whether a stage has run.
56 / 0x38	GetQuestRunning	Gate by whether a quest is active.
53 / 0x35	GetScriptVariable	Read a script variable.
79 / 0x4F	GetQuestVariable	Read a quest-script variable.
69 / 0x45	GetItemCount	Inventory check.
76 / 0x4C	GetDisposition	NPC disposition toward the player.

OR-chain rule: to mean "A OR B OR C", set the OR flag on every CTDA in the chain except the last; the last is AND.

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How to use this skill

• Understanding a record → references/records.md for the exact layout, then check a real example in export/Oblivion.esm/<TYPE>.txt.
• Reasoning about why a topic reaches (or doesn't reach) an NPC → walk references/checklist.md; it's usually AddTopic visibility, a quest not running, or a GetIsID condition.
• Reading/decoding a CTDA → references/conditions.md for offsets, the OR rule, the parameter-type table, and function indices.
• Inspecting real data → the dump in export/Oblivion.esm/ (DIAL.txt, INFO.txt, QUST.txt, IDLE.txt, PACK.txt) is the actual Oblivion.esm content.