Derivation Graph

Every render in 360 Hextile has a derivation graph — a visual tree showing exactly how it was created. Each node represents an operation applied to the image, and edges show parent-child relationships. The graph tracks the complete lineage from the original source image through every pass, edit, and transformation to the current state.

Understanding the Graph

Nodes are connected by lines showing parent-to-child relationships. The highlighted node is the active or head node — the one you are currently viewing. When you fork a render, the graph creates parallel branches, each representing a different creative direction.

The graph reads left to right (or top to bottom in compact mode), with the source image at the root and later operations branching outward.

Node Types (Ops)

Each node has an operation type that describes what it represents:

Each node carries its own metadata: the operation type, timestamp, a preview thumbnail URL, and a full-resolution image URL.

Draft vs final nodes (Spot & Tile Preview)

Viewer tools Spot Edit and Tile Preview materialize GPU previews as graph nodes with status: draft before they become project steps:

• Draft — uncommitted tool work. Not the graph head. Close tool = detach/re-adopt, not automatic delete.
• Commit in the tool = promote the active draft into a final step (head advances).
• Discard in the tool = deliberate delete of draft / residual pin work.
• Multiple drafts may exist as a variation set (filmstrip) while pose is fixed — see Spot Editing and Tile Preview.

Orthogonality: graph node status: draft is not the same field as a hextile config tile state: draft|baked. Config bake for a Spot/Tile Preview promote happens when the tool commits, not when the draft is first created.

Do not treat API WebSocket tile_preview progress frames as these graph drafts.

Linear Lineage

Walking from any node back to the root follows a single source-first path called the lineage chain. Each node knows its treeParentId, forming a linked list back to the source. This chain is the exact sequence of operations that produced that node's image — no branching, no ambiguity.

The lineage is always linear within a single branch. Forks create additional branches, but each branch has its own distinct linear chain.

Fork Lanes

When you fork a render, each parallel branch gets its own lane in the graph visualization. Fork depth determines lane assignment — the first fork splits into adjacent lanes; deeper forks shift further out. This keeps the visual layout clean even with multiple concurrent branches.

Each fork is a full independent lineage. Operations applied to one fork do not affect the other.

GraphPanel

The GraphPanel is the interactive graph viewer embedded in the render detail page. It displays:

• Node cards with op type icons and timestamps
• Branch lines connecting parent and child nodes
• Lane columns separating parallel forks
• Source recipes — click any source node to inspect its original prompt and settings
• Pass recipes — select a pass node to inspect its configuration, rendered tiles, and collapsed Stored parameters
• Scrub navigation — drag through nodes to preview each version in sequence

Graph views

Open the slider menu in the Detail GRAPH header to choose the tree view:

• Head tree (default) starts from the current head and shows its recent ancestry. Show Last changes how many older steps stay visible.
• Linear tree shows the source-first branching layout.
• Collapse to Head opens the existing confirmation flow for removing every non-head step in the selected head chain. It is disabled when there is no safe chain to collapse.

The Linear/Head choice and Show Last value persist and are shared with the dock Graph view. If a document has no valid head spine, the panel falls back to Linear without discarding the saved preference.

Node Image URLs

Each graph node exposes two image URLs:

• Preview — a JPG thumbnail that loads instantly for quick scanning and scrubbing
• Full — the complete PNG at render resolution, available on demand

The preview is used throughout the UI (graph cards, render lists, navigation steppers). The full URL is fetched when you open a node in the 360 viewer or request a download.

Head vs Active Node

The head is the latest node in the current branch — the tip of the linear chain from source through the most recent operation. Every branch has exactly one head.

You can navigate to any node to make it the active node for further operations. Clicking an earlier node activates it. Choose Current pass or All passes from the header RENDER menu, or run another edit or transformation, to create a new child from that point. This is how you rewind the graph and try a different direction without losing the work ahead.

The viewer's single Resize popover can create either operation: an absolute Size destination creates a resize node, while a native-relative Upscale factor creates an upscale node. Both branch from the node you are viewing.

Switching active nodes does not delete anything — all nodes remain in the graph, and you can always navigate back.

Related guides: - Multipass — Understanding pass nodes and progressive refinement - Spot Editing — Draft nodes, Commit/Discard, lock multi-draft - Tile Preview — Face drafts, filmstrip, next-face Render - De-Pinch — Pole correction workflow - Upscale — Resolution increase operations