Build System

Overview

The project uses CMake with optional third-party submodules providing the Windows API compatibility layer.

Directory Structure

CMakeLists.txt
cmake/
└── ThirdPartySDL.cmake      ← SDL3 integration
third_party/
├── SDL/                     ← SDL3 (windowing, input, audio)
├── SDL_image/               ← BLP image loading
└── SDL_mixer/               ← audio mixing

Build Targets

Target	How to build
Linux / Desktop	`cmake -S . -B build && cmake --build build`
Web (Emscripten)	`emcmake cmake -S . -B build-web && cmake --build build-web`
Android	See `ANDROID.md`
Windows	Visual Studio: open `planetblupi.sln`, or CMake with MSVC

The main executable is named PLANET_BLUPI_WINDOWS (name kept for compatibility).

Dependencies

Library	Purpose
SDL3	Window creation, input handling, timing, 2D rendering surface
SDL_image	Loading BLP image files (Epsitec format)
SDL_mixer	Audio mixing for WAV sound effects
Free Direct	DirectDraw/DirectSound → SDL3 wrapper
Free API	Win32 API → cross-platform wrapper

Compatibility Layer Architecture

Planet Blupi source code
        │
        │ uses Win32 API + DirectX API
        │
Free API + Free Direct (wrapper layer)
        │
        │ implements Win32/DirectX calls using:
        │
SDL3 + SDL_image + SDL_mixer
        │
        │ runs on:
        │
Linux / Web (Emscripten) / Android / Windows

Platform Notes

Windows

Native build using Visual Studio solution (planetblupi.sln, planetblupi.vcxproj). DirectDraw and DirectSound run natively without the compatibility layer.

Linux

Requires the Free Direct / Free API layer. SDL3 provides windowing and audio.

Web (Emscripten)

Uses Emscripten SDK (emcmake, emmake)
MIDI music does not work (MCI API unavailable)
AVI movies do not work (MCI API unavailable)
Save games use IndexedDB via IDBFS — see Web Persistence

Android

Experimental. See ANDROID.md for platform-specific build instructions.