markrussinovich/doompaint

Purpose and entry points

MS Paint Doom runs ViZDoom headlessly, then displays real Doom frames by pasting them into Microsoft Paint as clipboard images. run.bat is the primary Windows launcher; it creates the environment, installs dependencies, and updates ViZDoom’s OpenAL DLL. Python orchestration starts in mspaintdoom/main.py; run_debug.bat enables live input diagnostics.

Game orchestration and timing

mspaintdoom/main.py owns startup, CLI options, lifecycle, pause/focus behavior, and the self-clocking render/paste loop. The engine advances independently at Doom’s 35 Hz; paste publication waits for both a new engine frame and evidence that Paint consumed the previous clipboard data. This keeps simulation real-time while limiting visible output to Paint’s throughput.

• mspaintdoom/main.py

• mspaintdoom/engine_vzd.py

ViZDoom engine boundary

engine_vzd.py configures and drives ViZDoom/ ZDoom: WAD selection, map, skill, resolution, action inputs, frame extraction, and engine sound reset behavior. It uses the bundled shareware IWAD by default; ViZDoom-provided Freedoom supports unavailable episodes/maps. The WAD is game content, not application logic.

• mspaintdoom/engine_vzd.py

• wad/doom1.wad

• requirements.txt

Paint output and window control

paint_out.py launches/manages Paint, prepares its canvas, chooses zoom, and executes the validated paste route. Preferred output is synthetic Ctrl+V; UI Automation’s Edit > Paste is the fallback after repeated failed consumptions. Frames remain floating selections; each subsequent paste implicitly commits the prior frame, preserving Paint undo history as frame history.

• mspaintdoom/paint_out.py

• mspaintdoom/sendinput.py

• mspaintdoom/capture.py

OLE clipboard serving

Instead of replacing clipboard contents per frame, clipserve.py exposes a persistent Windows OLE IDataObject whose image bytes are updated in place. Paint retrieves DIB data through GetData; this avoids freeing data during Paint’s asynchronous paste read. Clipboard consumption is also the pacing acknowledgment. Clipboard-loss detection permits another application’s copy operation while paused and reclaims ownership only when publishing resumes.

• mspaintdoom/clipserve.py

• exp_ole_clip.py

Input isolation and control translation

A low-level Windows keyboard hook captures gameplay keys only while Paint is foreground, preventing arrows, shortcuts, and selection movement from affecting Paint. Input is sampled at engine-tic cadence with tap latching. Ctrl+Z is specially reinjected so Paint undo remains available; failure to install the hook falls back to asynchronous key polling.

• mspaintdoom/keys.py

• mspaintdoom/sendinput.py

• mspaintdoom/main.py

Audio and platform dependencies

Engine effects use ViZDoom/OpenAL; startup and runtime recovery reset ZDoom sound when metering indicates silent output. Separate music handling reads WAD music lumps, converts MUS where required, and plays MIDI through Windows MCI, synchronized with focus pause state. This is Windows-specific software relying on Win32 input, clipboard/OLE, UI Automation, Paint, MCI, ViZDoom, and OpenAL. The launcher replaces ViZDoom’s older OpenAL with the included version for default-device tracking.

• mspaintdoom/music.py

• third_party/OpenAL-COPYING.txt

• run.bat