Alien Breed 3D I

Alien Breed 3D I - AmigaOS4 Port
=================================
Ported by: Claude/Maijestro
Based on: Alien Breed 3D HD by retro-foundry
Source: https://github.com/retro-foundry/Alien-Breed-HD

*** BETA RELEASE - WORK IN PROGRESS ***
This is an early beta release. The upstream project (Alien Breed 3D HD) is
under active development and many features are not yet implemented.
Please report bugs and issues to help improve future versions.

DESCRIPTION
-----------
This is a native AmigaOS4 PowerPC port of Alien Breed 3D I, based on the
open-source C reimplementation by retro-foundry. The original game was
developed by Team17 in 1995 for the Amiga AGA chipset and is now playable
natively on AmigaOS4 systems.

The port translates the original 68000 assembly code into C and uses SDL2
for display, input and audio. All original Amiga data formats and game
behavior are preserved where possible.

REQUIREMENTS
------------
- AmigaOS 4.1 Final Edition
- SDL2 library
- ogles2.library (recommended for display output)
- 256 MB RAM minimum
- Warp3D Nova compatible graphics card (recommended)

TESTED ON
---------
- X5000 (AmigaOS 4.1 Final Edition)
- QEMU Pegasos2 emulation

INSTALLATION
------------
1. Extract the archive to a location of your choice
2. Edit ab3d.ini to suit your system (see CONFIGURATION below)
3. Double-click ab3d1 to start
4. Create an icon using your preferred icon editor (not included)

CONFIGURATION (ab3d.ini)
------------------------
Key settings for AmigaOS4:

  render_width=640     ; Internal render resolution (affects speed)
  render_height=480    ; Lower = faster, higher = better quality
  window_width=1024    ; Window size (windowed mode only)
  window_height=768    ; Window size (windowed mode only)
  display_mode=windowed ; windowed or fullscreen
  start_level=1        ; Starting level (1-16)
  volume=100           ; Sound volume (0-100)
  show_fps=1           ; Show FPS counter

GRAPHICS & PERFORMANCE
----------------------
The game uses a software renderer for all 3D graphics. The display output
is handled via SDL2 with the compositing or opengles2 backend.

Full OpenGL hardware acceleration is NOT available on AmigaOS4 because
the game requires OpenGL 3.0+ features (integer textures GL_R16UI,
GLSL #version 330) which are not supported by ogles2.library or gl4es.

As a result, all 3D rendering is done on the CPU. Performance depends
heavily on the internal render resolution set in ab3d.ini:

  640x480  render = ~30 FPS on X5000 (recommended, scales to fullscreen)
  800x600  render = ~15 FPS on X5000
  1024x768 render = ~5  FPS on X5000 (not recommended)

The window/fullscreen display is always at native desktop resolution
(e.g. 1920x1080) regardless of the internal render resolution.

Future versions may implement a GLES2-compatible render path.

GAME DATA
---------
All required game data is included in this archive, extracted from the
original open-source repository. No original Amiga disks or CD are needed.

NOTE: Alien Breed 3D I is a registered trademark of Team17. The original
game source code was released by Team17 for personal use in Amiga Format.

KNOWN ISSUES & MISSING FEATURES
--------------------------------
The following features are not yet implemented in the upstream C port
and are therefore also missing in this AmigaOS4 release:

- No main menu (game starts directly at level 1)
- No intro sequence or title screen
- No end screen / credits sequence
- No in-game music (tracker module playback not implemented)
- No save/load game functionality
- No multiplayer support
- OpenGL 3.0+ GPU acceleration not available on AmigaOS4

These features are planned for future upstream releases. This port will
be updated as the upstream project progresses.

CHANGES FROM ORIGINAL PORT (AmigaOS4 specific)
-----------------------------------------------
- Big-endian (PowerPC) color correction for correct display output
- SDL_WINDOW_OPENGL flag fix to prevent 100% CPU hang on startup
- opengles2 renderer selected automatically via ogles2.library
- New window_width/window_height settings added to ab3d.ini
- Windowed mode enabled for AmigaOS4 release builds
- Variable name fix (amiga -> amiga_key) for AmigaOS4 SDK compatibility
- __builtin_nontemporal_store disabled for PPC GCC 11.5 compatibility

SOURCE CODE & PATCHES
---------------------
AmigaOS4 patches will be submitted upstream to:
https://github.com/retro-foundry/Alien-Breed-HD

CREDITS
-------
- Original game: Team17 (1995)
- C reimplementation: retro-foundry
- AmigaOS4 port: Maijestro (2026)
- Built with: GCC 11.5.0 PPC cross-compiler (adtools)
- Libraries: SDL2, ogles2.library, libpthread