NXEngine-evo
Description:	nxengine refactoring
Download:	nxengine-evo.lha       (TIPS: Use the right click menu if your browser takes you back here all the time)
Size:	26Mb
Version:	2.6.5
Date:	03 Sep 2026
Author:	Falke_34
Submitter:	Falke_34
Email:	falke 34/gmx de
Homepage:	http://falke34.bplaced.net
Requirements:	SDL2
Category:	game/platform
License:	GPL
Distribute:	yes
Min OS Version:	4.1
FileID:	14062
Comments:	0
Snapshots:	0
Videos:	0
Downloads:	9  (Current version)
	9  (Accumulated)
Votes:	0 (0/0)  (30 days/7 days)

Short:        NXEngine-evo 2.6.5, Cave Story open-source engine (SDL2)
Uploader:     Falke_34
Author:       nxengine-evo contributors, AmigaOS4 port by Falke_34
Type:         game/plat
Version:      2.6.5
Requires:     SDL2
Architecture: ppc-amigaos >= 4.1.0


DESCRIPTION

NXEngine-evo is an open-source reimplementation of the engine behind
Cave Story (Doukutsu Monogatari), the acclaimed freeware action-
platformer by Daisuke "Pixel" Amaya. The game features tight run-and-
gun gameplay across handcrafted underground levels, a memorable cast
of characters, branching story paths, and multiple endings.

This is a native AmigaOS 4.1 PPC build using SDL2 and SDL2_mixer for
audio/input, with SDL2_image for graphics loading. No OpenGL or
ogles2.library is required; rendering runs entirely through SDL2's
software renderer.

Two executables are included:
- NXEngine-evo  : the main game
- nxextract     : a companion tool to convert the original Cave Story
                  data files into the format NXEngine-evo expects
                  (see INSTALLATION for when you need this)


INSTALLATION

NXEngine-evo requires the original Cave Story (Doukutsu Monogatari)
freeware game data, which is NOT included in this archive for copyright
reasons. The engine data bundled here (fonts, stage metadata) is not
enough to play.

You need one of the following:

A) Pre-extracted data (easiest):
   If you already have a working Cave Story installation on another
   platform, copy its "data" folder contents into the "data" drawer
   next to NXEngine-evo, merging with the engine data already there.

B) Extract from the original freeware Windows executable (Doukutsu.exe):
   1. Obtain the original Cave Story freeware release (Doukutsu.exe,
      freely available from the developer's website and archive.org).
   2. Copy Doukutsu.exe into the NXEngine-evo drawer.
   3. Run "nxextract" from Shell:
        cd NXEngine-evo-AmigaOS4
        nxextract
      nxextract converts the data embedded in Doukutsu.exe into the
      separate files NXEngine-evo expects and places them in "data".
   4. Delete Doukutsu.exe afterwards (no longer needed).

Once the game data is in place:
1. Copy the whole NXEngine-evo-AmigaOS4 drawer to wherever you like,
   keeping the "data" drawer next to the "NXEngine-evo" executable.
2. Double-click the NXEngine-evo icon, or start it from Shell.

Settings (settings.dat) and save files (profile.dat) are stored
directly in the game drawer, next to the executable.


KNOWN ISSUES / TESTING STATUS

Please treat this build as early/experimental:

- Game data must be sourced separately (see INSTALLATION). The archive
  deliberately ships without the Cave Story freeware data; the engine
  starts but immediately aborts if the data is absent or incomplete.

- If the game aborts at startup with a message about a missing file,
  check that the "data" drawer is present and fully populated directly
  next to the NXEngine-evo executable. Running nxextract again from
  within the game drawer is the fastest way to repopulate it.

- A stale or incomplete save file from a very early test run (stored
  under ENVARC:nxengine/ in previous builds) will not be read by this
  release - saves now live next to the game. If you see a "savefile
  error" on the very first launch, check for and delete any leftover
  ENVARC:nxengine/profile*.dat files from earlier experiments.

- This port has been tested on emulated AmigaOS 4.1 (QEMU/PPC). If
  you encounter unexpected crashes or graphical glitches on real
  hardware, please report them (see CONTACT).


CHANGES IN THIS PORT (compared to upstream NXEngine-evo 2.6.5)

- Native AmigaOS4/SDL2 PPC build (cross-compiled via Docker with
  ppc-amigaos-gcc 11, CMake-based build system)
- Big-endian audio fix: SDL2 audio format changed from AUDIO_S16
  (hard-wired Little-Endian alias) to AUDIO_S16SYS (native byte
  order); without this, all sound output is white noise on PPC
- Savegame reliability fix: profile.dat is now pre-allocated before
  writing, so save files are always the correct size regardless of
  the filesystem's sparse-file behaviour (AmigaOS4 does not guarantee
  POSIX-style zero-fill for seek-gaps)
- Settings and save files stored in the game drawer (PROGDIR:) rather
  than the system-wide ENVARC:nxengine/ directory
- No Shell/console window opened when started from Workbench; log
  output goes to debug.log in the game drawer instead
- Data path via SDL_GetBasePath() (no hardcoded Linux install prefix)
- AmigaOS4 platform detection added to ResourceManager (fileExists),
  which would otherwise hit a compile-time "#error Platform not
  supported"
- C++ dialect changed to gnu++11 for POSIX visibility under newlib
  (POSIX functions such as fileno()/isatty() are hidden by
  -std=c++11/__STRICT_ANSI__ on AmigaOS4-newlib)
- gthread stub providing AmigaOS4-native SignalSemaphore-backed
  __gthread_mutex_* symbols required by libstdc++ (the engine itself
  is single-threaded throughout)
- Stack cookie set to 4 MB ($STACK: 4000000); $VER tag included


CREDITS / THANKS

- Daisuke "Pixel" Amaya, for creating Cave Story / Doukutsu Monogatari.
- The nxengine-evo contributors, for maintaining the open-source
  engine reimplementation.
- Everyone involved in SDL2, SDL2_mixer, and SDL2_image.
- The AmigaOS4 SDL2 port maintainers (kas1e/AmigaPorts).


CONTACT

Please report bugs or feedback via the os4depot.net comments, or the
AmigaOS4 community forums (thread by Falke_34). Please include the
debug.log from the game drawer (or the Shell output) when reporting
a problem, along with a description of what you were doing when it
occurred.


SOURCE / LICENSE

See the LICENSE file included in this archive (copied from the source
repository) for the exact license terms.
Full upstream source: https://github.com/nxengine/nxengine-evo
The AmigaOS4-specific changes in this port are provided under the same
license as the files they modify.