This note captures the current class-level read of the `SpriteNode` family so later Ghidra class work can move quickly and conservatively.
Compared with `EntityDispatchEntry`, this family has a cleaner explicit virtual/event-dispatch surface and a more bounded ownership model. That makes it an excellent second pilot for class lifting.
## Current Best Class-Level Read
`SpriteNode` is a tree-based render/UI node family with:
- child-chain ownership
- accumulated position and bounds propagation
- dirty-state tracking
- central event dispatch through a small virtual surface
- destructor ownership over child nodes and global focus state
This already looks much closer to an ordinary C++ object family than many gameplay-side structures.
## Strongest Evidence Anchors
### Destructor
#### `000b:326e` `sprite_node_destroy`
Current best read:
- destructor-style path
- sets vtable ptr to `0x501a`
- clears global focus pointer `[0x4fd0:0x4fd2]` if `self`
- releases child nodes
- frees object memory through `mem_free`
This is the strongest current single proof that `SpriteNode` should be lifted as an owned object family.
### Event dispatch
#### `000b:3ab2` `sprite_node_dispatch_event`
Current best read:
- large event dispatch switch
- checks event types `2/4/8/0x100`
- updates global focus pointer at `[0x4fd0:0x4fd2]`
- dispatches through virtual slots `+0x14`, `+0x18`, `+0x20`, `+0x24`
This is the strongest current proof of a stable virtual method surface.
### Dirty/update family
-`000b:3380 sprite_node_is_dirty`
-`000b:33a6 sprite_node_mark_dirty`
-`000b:40ee sprite_node_update_and_dispatch`
These show that node state changes and redraw/update dispatch are methods on the same family, not just free helper functions wandering across unrelated data.
### Recursive tree helpers
-`000a:b988 sprite_node_get_or_traverse`
-`000b:358d sprite_tree_accumulate_pos`
-`000b:3a00 sprite_tree_sum_x_offset`
-`000b:3a35 sprite_tree_sum_y_offset`
These are strong evidence for a child-linked tree object with inherited coordinate accumulation.
## Candidate Layout
This layout is intentionally conservative.
| Offset | Current name | Confidence | Current meaning |
|---|---|---|---|
| `+0x19/+0x1b` | `child_or_next_ptr` | High | Child-chain pointer pair used by recursive traversal and offset accumulation. |
| `+0x21` | `local_x_offset` | High | Summed by `sprite_tree_sum_x_offset` / accumulate helpers. |
| `+0x23` | `local_y_offset` | High | Summed by `sprite_tree_sum_y_offset` / accumulate helpers. |
| `+0x29` | `dirty_flags` | High | Checked by `sprite_node_is_dirty`; manipulated by mark/update paths. |
| `+0x17e` | `redraw_flag` | Medium | Cleared by `sprite_clear_redraw_flag`; likely a subtype or larger-object field tied to one SpriteNode family variant. |
## Layout Caveat
The current notes likely mix a compact core `SpriteNode` with one or more larger derived UI/display objects. The evidence for `+0x17e` strongly suggests there are bigger family members or wrapper objects in the same virtual ecosystem.
So the safe future modeling strategy is:
- define a small `SpriteNodeBase`
- keep larger UI/display fields in derived or sibling structs until more offsets are closed
## Candidate Method Map
### Strong instance methods
| Address | Current function | Candidate method role |
-`000a:7b58` returns zero and behaves like a default no-op boolean slot
-`000a:7b5f` is a forwarding trampoline slot
These likely belong to one or more shared/default node vtables and should be preserved as vtable evidence even if they never become pretty source-level methods.
## Ownership And Global State
### Focus/global state
Global focus pointer `[0x4fd0:0x4fd2]` is updated in the dispatch family and cleared in the destructor.
That gives the family a real interaction with global UI focus/state, but the key point for class work is simpler:
- focus ownership is tied to the node family itself
- this is not just an arbitrary free helper changing global UI state
### Child ownership
The destructor and recursive sum/traverse helpers strongly suggest real child ownership or at least managed child linkage.
That means later class modeling should preserve a node/tree mental model rather than flattening everything into stand-alone display items.
## Candidate Ghidra Modeling Plan
When class authoring begins, the safest sequence for this family is:
1. create class namespace `SpriteNode`
2. move `Destroy`, `IsDirty`, `MarkDirty`, `DispatchEvent`, `UpdateAndDispatch`, and `GetOrTraverse` first
3. create minimal `SpriteNodeBase` struct with the stable offsets around `+0x19`, `+0x21`, `+0x23`, and `+0x29`
4. create provisional vtable with slots `+0x14`, `+0x18`, `+0x20`, `+0x24`
5. keep recursive tree helpers outside the class until decompiler output shows they benefit from becoming methods
Verified first live `SpriteNode` batch landed on 2026-04-08.
- Created class owner `Remorse::SpriteNode` in the active `CRUSADER.EXE` database.
- Re-anchored the strongest old `000b:` method batch into the live `1360:` segment by preserved offset delta from `000b:326e -> 1360:046e`.
- Created minimal live datatypes `/Remorse/SpriteNodeBase` and `/Remorse/SpriteNodeVtable` from the current safest note anchors.
-`/Remorse/SpriteNodeBase` currently names only the bounded field block that is directly supported by the live method batch:
-`+0x19 = child_or_next_farptr`
-`+0x21 = local_x_offset`
-`+0x23 = local_y_offset`
-`+0x29 = dirty_flags`
-`/Remorse/SpriteNodeVtable` is still the earlier minimal shell in-session, but the live `DispatchEvent` read now supports a deeper slot map than the first authoring batch encoded:
- direct self dispatch uses `+0x04`, `+0x08`, `+0x0c`, `+0x10`, `+0x14`, `+0x18`, `+0x1c`, and `+0x24`
- child broadcast during event `0x40` uses child slot `+0x34`
- Moved the first bounded method set under the class owner with short provenance comments:
-`1360:036a` -> `Create` (best current constructor-style anchor; still keep the higher-wrapper caveat visible)
- The live decompiler now makes the core family surface much easier to navigate directly in-session:
-`Create` now exists live as the current safest constructor-style anchor: it allocates `0x34` bytes when `this` is null, stamps the `0x501a` SpriteNode vtable, initializes the child-link/core offset fields, and links the incoming parent/child lane.
- Direct callers now narrow the subtype story materially: the current call set is dominated by `GumpCreate_*` and adjacent UI wrapper constructors, which supports treating `Create` as the compact shared base-node constructor used by higher-level gump/display objects rather than as a one-off derived leaf.
-`Destroy` restores the `0x501a` base vtable, clears the global focus pointer when `this` owns it, releases child linkage, and optionally frees self.
-`IsDirty` and `MarkDirty` read and mutate the `+0x29` dirty-state lane exactly as the note predicted.
-`GetOrTraverse` now exists live as the best current `000a:b988` re-anchor: it recursively walks the child-linked subtree, adjusts the incoming query coordinates by the local offsets, and returns either the matched child node or the default sentinel through the out pointer.
-`DispatchEvent` updates the global focus pointer at `0x4fd0:0x4fd2` and now ties concrete event codes to concrete slot offsets: `1/2/4/8 -> +0x04/+0x08/+0x0c/+0x10`, `0x10/0x20 -> +0x14/+0x18`, `0x40 -> child +0x34 then optional self +0x1c`, and `0x100 -> +0x24`.
-`UpdateAndDispatch` now clearly shows the `IsDirty` / `MarkDirty` / recompute / child-walk sequence instead of staying as an anonymous seg1360 helper.
- The `SpriteNode` family is therefore no longer note-only. What remains open is narrower now: chiefly whether `Create` should remain the family's public constructor-style entry or later be split into a higher derived/UI wrapper and a smaller base-node constructor once more callers and subtype evidence land, plus the deeper vtable-slot and subtype-layout questions.
- whether the current `Create` signature itself can be cleaned up further now that its caller set points to a shared compact base-node constructor used by higher-level gump wrappers
- whether the recovered event-code map can now be promoted from raw event-code labels to prettier semantic slot names without overfitting UI behavior too early
- whether `sprite_tree_accumulate_pos` should become a class method, a static helper, or a separate geometry utility
## Immediate Follow-Up Value
The most useful next companion work after this note is not more sprite detail by itself. It is the rebuild-ABI note, because once the first few class families are documented this well, the next real risk is drifting away from the original memory and calling-convention model before any code is emitted.
