Comfyui-JSON-Manager/docs/plans/2026-04-04-binary-index-decoder-design.md

BinaryIndexDecoder Node — Design

Summary

A standalone ComfyUI utility node that converts an integer index into 3 boolean outputs using binary (bit-field) encoding. Intended for use with loop counters to gate multiple processing branches simultaneously.

Node Spec

Field	Value
Class name	BinaryIndexDecoder
Display name	Binary Index Decoder
Category	JSON Manager/utils
Function	decode

Inputs

Name	Type	Default	Range
index	INT	0	0–7

Outputs

Name	Type
flag_0	BOOLEAN
flag_1	BOOLEAN
flag_2	BOOLEAN

Logic

flag_0 = bool((index >> 0) & 1)
flag_1 = bool((index >> 1) & 1)
flag_2 = bool((index >> 2) & 1)

Truth table

index	flag_0	flag_1	flag_2
0	F	F	F
1	T	F	F
2	F	T	F
3	T	T	F
4	F	F	T
5	T	F	T
6	F	T	T
7	T	T	T

Implementation Notes

• Lives in project_loader.py alongside other project nodes
• Added to PROJECT_NODE_CLASS_MAPPINGS and PROJECT_NODE_DISPLAY_NAME_MAPPINGS
• No JavaScript extension needed (no source sync, no dynamic widgets)
• No NiceGUI UI changes needed
• IS_CHANGED not needed (output is deterministic from input)

Testing

9 tests in tests/test_project_loader.py::TestBinaryIndexDecoder:

• Input types include index as INT
• All 8 index values (0–7) produce correct boolean tuple
• Out-of-range index (e.g. 8) clamps to 0–7 or wraps gracefully
• NodeMappings test updated: 5 nodes, mappings length == 5