SDL Trading Platform

A high-performance, multithreaded cryptocurrency trading interface built from scratch in C++ using SDL3.

Overview

This project is a custom-built trading terminal designed for speed and responsiveness. It provides real-time market data visualization, order book tracking, and chart drawing capabilities without the overhead of heavy web frameworks like Electron. Built directly on top of SDL3, it uses a callback-driven render loop and a multi-threaded architecture so the UI stays smooth (60+ FPS) while background threads poll external APIs for market data.

Features

• Interactive Candlestick Charts: Smooth panning, price/time zooming, auto-scaling, and multiple timeframes (1m … 1w).
• Drawing Toolbox: Left-hand toolbox to annotate charts with interactive vector tools:
  • Cursor & Crosshair
  • Trend Lines
  • Horizontal Lines
  • Text Notes
• App Navigation Tabs: Top-level tabs (Markets, Trades, Bots, Strategies, Backtesting, Exchanges, Account, Configuration). Unimplemented tabs show a placeholder.
• Real-time Market Panels:
  • Order Book: Live bid/ask spread and depth visualization.
  • Recent Trades: Scrolling list of the most recent market executions.
  • Market Table: Browse Spot and Futures pairs, sort by volume or 24h change, search, and save symbols to Favorites.
• Alerts System: Create, edit, delete, and toggle custom price alerts. Persists to alerts.json. Optional Telegram notifications via libcurl.
• Borderless Window Chrome: Custom titlebar with live stats, minimize/maximize/restore/close, edge resize, and Aero-style snap (top / left / right).
• Customizable Layout: Resizable panels with draggable horizontal and vertical dividers.
• Custom UI Engine: Lightweight immediate-mode drawing with Dark / Light / System theme support.

Architecture

The application uses the SDL3 main-callback paradigm (SDL_AppInit, SDL_AppIterate, SDL_AppEvent, SDL_AppQuit), forwarded from a thin src/main.cpp into src/app/:

Concern	Location
Shared types, AppState, layout	src/core/
Lifecycle (init / event / render / quit)	src/app/
Borderless window, titlebar, snap, hit-test	src/window/
Draw primitives, tabs, toolbox, chrome	src/ui/
HTTP, favorites, account mock	src/services/
Chart, table, orderbook, trades, alerts	src/modules/

• State: A centralized AppState (src/core/app_state.hpp) is passed as AppState* to every update/render function. Layout rectangles live in state->layout, recomputed by update_layout().
• Concurrency: Background threads (fetch_candles, fetch_orderbook, fetch_trades, fetch_pairs, alerts_engine, …) poll APIs; shared data is guarded with std::mutex.
• Rendering: Immediate-mode helpers in src/ui/ui_utils.hpp (ui_fill_rect, ui_draw_text, …).

For the full module map and public function reference, see docs/ARCHITECTURE.md.

Requirements

• C++20 compiler
• CMake 3.16+
• libcurl
• By default, CMake fetches via FetchContent (DOWNLOAD_DEPENDENCIES=ON):
  • SDL3, SDL3_ttf, SDL3_image
  • nlohmann/json
• Or install those packages system-wide and configure with -DDOWNLOAD_DEPENDENCIES=OFF
• Optional: -DENABLE_TELEGRAM=ON (default) for Telegram alert notifications

Build Instructions

# Configure
cmake -B build -S .

# Build (example: 4 parallel jobs)
cmake --build build -j4

# Run
./build/sdl-trading

Project Structure

SDL_Trading/
├── CMakeLists.txt
├── README.md
├── AGENTS.md                 # Guidelines for LLM agents
├── docs/
│   └── ARCHITECTURE.md       # Module map & function reference
├── res/fonts/                # JetBrains Mono + icon font (sdl-trading.ttf)
├── alerts.json / favorites.json   # Local persistence (runtime)
└── src/
    ├── main.cpp              # SDL3 callback entry (thin wrapper)
    ├── core/                 # Shared foundations
    │   ├── types.hpp         # Candle, PairInfo, Alert, AppTab, …
    │   ├── constants.hpp     # Window defaults, font/icon paths
    │   ├── app_state.hpp     # Central AppState + AppLayout
    │   ├── layout.hpp
    │   └── layout.cpp        # update_layout()
    ├── app/                  # SDL3 lifecycle
    │   ├── app_init.*        # Setup, fonts, threads
    │   ├── app_event.*       # Input routing (coordinate-based)
    │   ├── app_render.*      # Per-frame draw loop
    │   └── app_quit.*        # Shutdown & persistence
    ├── window/               # Borderless window chrome
    │   ├── titlebar.*
    │   ├── window_snap.*
    │   └── window_hit_test.*
    ├── ui/                   # Drawing & chrome widgets
    │   ├── ui_utils.*
    │   ├── theme.*
    │   ├── app_tabs.*
    │   ├── toolbox.*
    │   └── chrome.*          # Dividers, notifications, placeholders
    ├── services/             # Infrastructure
    │   ├── network.*         # HTTP GET/POST, Telegram
    │   ├── favorites.*
    │   └── account.*         # Mock balance / PNL thread
    └── modules/              # Feature panels
        ├── chart.*
        ├── market_table.*
        ├── orderbook.*
        ├── trades.*
        ├── alerts.*
        └── right_panel.*

License

See LICENSE.