ori-term

A GPU-accelerated terminal emulator written from scratch in Rust.

ori-term combines terminal emulation, pane multiplexing, and a custom GPU-rendered UI framework into one application. Instead of stacking terminal + tmux + scripts + glue, ori-term collapses that stack into one coherent system.

Cross-platform (Windows, Linux, macOS) from day one — no platform is primary, no platform is an afterthought.

Status: alpha. Core terminal emulation, GPU rendering, split/floating panes, tabs, and the UI framework are functional. Daemon mode, session persistence, remote attach, and the TUI client are on the roadmap.

Architecture

Five-crate workspace with strictly one-way dependencies:

oriterm_ipc  (standalone — platform IPC transport)
oriterm_core (standalone — terminal emulation library)
oriterm_ui   → oriterm_core (UI framework)
oriterm_mux  → oriterm_core, oriterm_ipc (pane server)
oriterm      → oriterm_core, oriterm_ui, oriterm_mux (application shell)

• oriterm_core — Pure terminal emulation (grid, VTE handler, selection, search, image protocols). No GUI, no PTY, no platform code.
• oriterm_ui — GPU-rendered widget framework (layout, interaction, animation, theming). Testable headlessly via WidgetTestHarness.
• oriterm_mux — Flat pane server (pane lifecycle, PTY I/O, lock-free snapshots). Each pane has a dedicated IO thread.
• oriterm_ipc — Platform IPC transport (Unix domain sockets, Windows named pipes).
• oriterm — Application shell (winit event loop, wgpu rendering, font pipeline, session model, configuration).

Features

Terminal Emulation

• Full VTE escape sequence handling — SGR, cursor, erase, scroll regions, alternate screen, OSC, DCS, CSI
• Text reflow on resize — cell-by-cell reflow handling wide characters, wrapped lines, and scrollback
• Ring buffer scrollback with configurable history
• Mouse reporting — X10, normal, button-event, any-event with SGR encoding
• Synchronized output (Mode 2026)
• Hyperlinks — OSC 8 explicit + implicit URL detection with hover underline and Ctrl+click
• Kitty keyboard protocol — progressive enhancement, CSI u encoding, mode stack
• Bracketed paste, focus events (Mode 1004), charset support (G0/G1/G2/G3, DEC special graphics)
• Device attributes (DA1/DA2/DA3), device status reports, mode query (DECRQM)
• Terminfo query (XTGETTCAP), settings query (DECRQSS)
• Color queries and reset (OSC 4/10/11/12/104/110/111/112)
• Extended underline styles (curly, dotted, dashed, double) and underline color (SGR 58/59)
• Overline (SGR 53/55), window manipulation (CSI t)

Image Protocols

• Kitty Graphics Protocol — chunked transmission, placement, z-indexing, deletion, animation
• Sixel graphics — DCS-based decoding and display
• iTerm2 inline images — OSC 1337 imgcat-compatible
• GPU compositing — images rendered as GPU textures alongside the terminal grid
• LRU eviction with configurable memory limits

GPU Rendering

• wgpu with Vulkan + DX12 on Windows, Vulkan on Linux, Metal on macOS
• Staged render pipeline — Extract (snapshot) → Prepare (pure CPU) → Render (GPU submission)
• Custom frameless window chrome — tab bar as title bar, pixel-drawn platform-specific window controls
• Window transparency — Mica/Acrylic on Windows, vibrancy on macOS
• Per-row damage tracking, instance buffer caching, partial updates, skip-present when idle

Font Pipeline

• Text shaping via rustybuzz (HarfBuzz) with two-phase shaping and ligature support
• Multi-face fallback — Regular/Bold/Italic/BoldItalic + configurable fallback chain with cap-height normalization
• Built-in glyphs — box drawing, block elements, braille, powerline via lookup table rasterization
• Color emoji — RGBA atlas pages, VS15/VS16 presentation selectors
• Subpixel rendering — LCD ClearType-style per-channel alpha (RGB/BGR)
• Subpixel positioning — fractional offset quantization
• Font synthesis — synthetic bold (embolden) and synthetic italic (14-degree skew) when faces are unavailable
• Configurable OpenType feature tags (liga, calt, kern, custom)
• Guillotine-packed multi-page glyph atlas (2048x2048), LRU eviction, R8Unorm + Rgba8Unorm pages
• DPI-aware auto-detected hinting modes
• ASCII pre-cache for fast startup

UI Framework

• GPU-rendered widgets — buttons, checkboxes, toggles, sliders, text inputs, dropdowns, labels, panels, scrollbars
• Drawing primitives — rects, rounded rects, shadows, gradients, borders
• Flexbox-style two-pass layout with Row/Column containers, Fixed/Fill/Hug sizing, padding, gap
• Overlay system — modals, context menus, tooltips
• Animation — easing functions, property transitions, animated values
• Dark/light themes derived from terminal palette with accent colors
• Widget-level hit testing with mouse capture and focus management
• Tab order, focus ring, keyboard accessibility
• Compositor layer system with scene caching and invalidation

Tabs & Window Chrome

• Tab reordering with smooth animation
• Tab tear-off into new windows and merge back (Chrome-style drag)
• Bell indicator on inactive tabs
• GPU-rendered context menus with shadows and rounded corners
• Settings overlay with color scheme selector
• Platform-specific window controls (Windows rectangular, macOS circular)
• Frameless drag, double-click to maximize, Aero Snap on Windows

Split Panes

• Split right (Ctrl+Shift+O) and split down (Ctrl+Shift+E)
• Immutable split tree with structural sharing via Arc
• Spatial navigation — Ctrl+Alt+Arrow to focus by direction
• Drag-to-resize dividers, keyboard resize with Ctrl+Alt+Shift+Arrow
• Equalize pane sizes (Ctrl+Shift+=), zoom/unzoom (Ctrl+Shift+Z)
• Undo/redo split history (Ctrl+Shift+U / Ctrl+Shift+Y)
• Close pane (Ctrl+Shift+W)
• Focus border — accent-colored on active, dimming on inactive
• Per-pane render cache with dirty checking

Floating Panes

• Toggle floating overlay (Ctrl+Shift+P)
• Float-tile toggle (Ctrl+Shift+G) — move panes between floating and tiled
• Mouse-driven drag and resize with snap-to-edge
• Z-ordering with drop shadows

Selection & Clipboard

• 3-point selection — anchor/pivot/end with sub-cell precision
• Word/line/block modes — double-click, triple-click, Alt+click
• Drag threshold (1/4 cell width) to prevent accidental selection
• Word boundaries — delimiter-class-aware expansion across soft wraps
• HTML formatted copy for pasting into rich text editors
• Copy on select (configurable), OSC 52 clipboard access
• Bracketed paste wrapping
• File drag-and-drop with auto-quoted path insertion
• Paste confirmation dialog for large/multi-line pastes (configurable)

Mark Mode

• Modal navigation toggled with Ctrl+Shift+M
• Cursor movement — arrows, Ctrl+Left/Right for words, Home/End for line, Ctrl+Home/End for buffer
• Extend selection with Shift+movement keys
• Enter to copy selection and exit, Escape to cancel
• Ctrl+A to select entire buffer
• PageUp/PageDown for page scrolling, auto-scrolls to keep cursor visible

Search

• Ctrl+Shift+F overlay with match count and navigation
• Plain text and regex search modes
• Highlighted matches across viewport and scrollback
• Next/previous keyboard navigation

Multi-Window

• Multiple windows sharing GPU device and surface management
• Cross-window tab movement
• Per-window DPI / scale factor handling

Color & Theming

• 24-bit truecolor, 256-color palette, 16-color ANSI
• 50+ built-in themes — Catppuccin, Dracula, Nord, Gruvbox, Solarized, Tokyo Night, and more
• TOML theme files with hot-reload via file watcher
• Light/dark auto-switch following system appearance
• Import from iTerm2, Ghostty, and base16 formats (via included converter tools)
• Minimum contrast enforcement (WCAG 2.0 luminance-based)

Configuration

• TOML config — fonts, colors, keybindings, behavior, window settings
• Hot reload — file watcher triggers live config updates
• Configurable keybindings with action binding
• Font size zoom — Ctrl+=/Ctrl+-, Ctrl+0 to reset

Shell Integration

• Shell detection — bash, zsh, fish, PowerShell
• OSC 7 CWD tracking
• OSC 133 semantic zone marking (prompt/input/output)
• Title management — OSC 2 or CWD short path
• Bell notification on background panes
• XTVERSION (CSI >q) identification response

Visual Polish

• Cursor blink with DECSCUSR steady/blinking styles
• Hide cursor while typing (reappears on mouse move)
• HiDPI with proper per-monitor scale factor handling

Cross-Platform

• Windows — ConPTY, DirectWrite font discovery, Vulkan + DX12, frameless with Aero Snap, Mica/Acrylic
• Linux — PTY, fontconfig, Vulkan, X11 + Wayland, D-Bus theme detection
• macOS — PTY, CoreText, Metal, native vibrancy (NSVisualEffectView)

Performance

• Per-row dirty tracking to minimize GPU work
• Instance buffer caching with partial updates for changed rows
• Ring buffer scrollback — O(1) push
• Zero allocations in hot render path — lock-free snapshot transfer via std::mem::swap()
• Zero idle CPU beyond cursor blink (~1.89 Hz)
• Buffer shrink discipline — grow-only buffers with post-render maybe_shrink()

Roadmap

These features are planned but not yet implemented:

• Daemon mode & IPC — background daemon keeping sessions alive, binary wire protocol, auto-start with fallback to in-process
• Session persistence — auto-save/restore of window/tab/pane layout, crash recovery, disk-backed scrollback archive
• Remote domains — SSH and WSL shell spawning with mixed local+remote panes
• Remote attach — TCP+TLS transport, predictive local echo (Mosh-style), bandwidth-aware rendering
• TUI client — terminal-in-terminal multiplexer (tmux replacement) connecting to the same daemon
• Tab hover preview — scaled-down live terminal thumbnail via offscreen render targets
• Vi mode — full vi-style navigation with count prefixes, f/t motions, bracket matching
• Hints / Quick select — vimium-style pattern matching for URLs, paths, git hashes with keyboard labels
• Command palette — Ctrl+Shift+P fuzzy-search action picker
• Lua scripting — event hooks, custom commands, post-processing shaders (WGSL)
• Terminal inspector — debug overlay with escape sequence log
• Quick terminal — global hotkey dropdown (Quake-style)
• Background images — PNG/JPEG background textures with configurable opacity
• Smooth kinetic scrolling — momentum scrolling for trackpads
• Progress indicators — OSC 9;4 taskbar progress
• Desktop notifications — native toast integration for OSC 9/99/777
• Native scrollbars
• Rich status bar
• macOS app bundle

See plans/roadmap/ for detailed section-by-section status.

Building

# Debug
cargo build --target x86_64-pc-windows-gnu

# Release
cargo build --target x86_64-pc-windows-gnu --release

# Checks
./clippy-all.sh
./test-all.sh
./build-all.sh

Cross-compiled from WSL targeting x86_64-pc-windows-gnu.

Inspiration

Project	What inspired us
Ghostty	Cell-by-cell text reflow approach
Alacritty	Term<T> architecture, FairMutex, VTE crate, strict clippy
WezTerm	Cross-platform PTY abstraction, multiplexer domain model
Chrome	Tab drag state machine, GPU-rendered UI, tab previews
VS Code	Frameless window chrome pattern
Windows Terminal	Selection behavior and clipboard UX
Bevy	Staged render pipeline (Extract → Prepare → Render)
tmux	Session persistence, daemon architecture, TUI multiplexing
Mosh	Predictive local echo, bandwidth-aware rendering
Catppuccin	Default color palette (Mocha)
Ratatui	Clippy lint configuration, testing patterns
termenv / lipgloss	Color profile detection cascade

The Name

ori — from the Japanese 折り (folding). Tabs fold between windows the way you fold paper.

License

MIT