Architecture

Threading Model

Main Thread (UI)                    Worker Thread (Rayforce)
┌─────────────────────┐            ┌─────────────────────────┐
│ GLFW + ImGui        │            │ Rayforce Runtime        │
│ - Render loop       │◄──obj_p───│ - Thread-local heap     │
│ - Zero-copy render  │            │ - Eval expressions      │
│ - User interaction  │───string──►│ - Widget objects        │
│ - Returns obj_p     │───obj_p───►│ - drop_obj cleanup      │
└─────────────────────┘            └─────────────────────────┘
         ▲                                    ▲
         └──────────── Queues ────────────────┘

Zero-Copy Data Flow

1. Rayforce evaluates query → produces obj_p (table/vector)
2. Passes raw obj_p to UI via queue (no serialization)
3. UI renders directly from columnar buffers
4. UI signals done → returns obj_p via queue
5. Rayforce calls drop_obj (refcount--)

No copies, no marshaling — pointer exchange only. Objects stay alive via refcount until UI releases.

Communication

Direction	Payload	Wake Mechanism
UI → Rayforce	Expression string	poll_waker_wake()
Rayforce → UI	obj_p	glfwPostEmptyEvent()
UI → Rayforce	obj_p to drop	(batched)