PlayDOOM - expert pour MetaTrader 5

This Expert Advisor runs the original DOOM (1993) inside MetaTrader 5's chart window. The game renders directly onto the chart using ObjectCreate with a bitmap label and ResourceCreate, while keyboard input is captured via OnChartEvent and forwarded to the DOOM engine running inside a custom DLL.

How It Works

The project has two components. The first is a Windows DLL that wraps the PureDOOM engine — a single-header, zero-dependency, pure C source port of DOOM designed to run on any platform. The DLL runs the game loop on a background thread, maintains a double-buffered framebuffer, and exposes simple exported functions for initialization, framebuffer retrieval, and key input. The second component is the MQL5 Expert Advisor, which calls the DLL every ~33ms via EventSetMillisecondTimer, copies the DOOM framebuffer (320x200 ARGB pixels) into a bitmap resource on the chart, and forwards keyboard events from the chart to the engine.

Since MQL5 does not provide CHARTEVENT_KEYUP events, key releases are detected by polling GetAsyncKeyState from user32.dll on each timer tick — a well-known workaround in the MQL5 community. The game runs at a smooth ~30 FPS, which matches DOOM's original 35hz tick rate closely.

Setup Instructions

Follow these steps carefully to get DOOM running on your chart:

1. Download MQL5.zip from the files attached to this publication.
2. Extract the zip. Inside you will find: Libraries\doomlib.dll, Experts\Doom\doom1.wad and the "For Devs" source code folder. Ignore this folder if you are not a developer.
3. Copy doomlib.dll to your terminal's MQL5\Libraries\ folder.
4. Create a folder called Doom inside MQL5\Experts\ and copy doom1.wad into it.
5. Compile DoomEA.mq5 in MetaEditor.
6. Attach the EA to any chart. In the EA settings dialog, check "Allow DLL imports".
7. The DOOM title screen should appear on the chart. Press Enter to start a new game.

Controls

Technical Details

• Engine: PureDOOM — a single-header C port of the original DOOM source code (id Software, 1993). No external dependencies.
• Rendering: The DLL provides a 320x200 ARGB framebuffer each frame. The EA writes it to a chart bitmap object via ResourceCreate with COLOR_FORMAT_ARGB_NORMALIZE.
• Threading: The DOOM game loop runs on a dedicated background thread inside the DLL. Double buffering with CRITICAL_SECTION synchronization ensures the EA can safely read the framebuffer at any time.
• Input: Keyboard events are captured in OnChartEvent (key-down) and polled via GetAsyncKeyState from user32.dll (key-up). A ring buffer inside the DLL queues input events for the game thread.
• Game data: Uses doom1.wad, the freely distributable shareware version (Episode 1: Knee-Deep in the Dead, 9 levels).

Files