==============================
Ngaro VM Implementation Status
==============================

+------------+--------------+---+---+---+---+---+---+---+---+
| Language   | File(s)      | A | B | C | D | E | F | G | H |
+============+==============+===+===+===+===+===+===+===+===+
| C          | retro.c      | x | x | x | x | x | x | x | x |
+------------+--------------+---+---+---+---+---+---+---+---+
| C          | libretro.c   | x | x | x | x | x | x | x | x |
+------------+--------------+---+---+---+---+---+---+---+---+
| C#         | retro.cs     | x | x |   | x | X | x | x |   |
+------------+--------------+---+---+---+---+---+---+---+---+
| Forth      | retro.fs     | x | x | x |   | x | x | x | x |
+------------+--------------+---+---+---+---+---+---+---+---+
| Go         | gonga/*      | x | x | x | x | x | x | x | x |
+------------+--------------+---+---+---+---+---+---+---+---+
| Lisp       | retro.lisp   | x |   |   |   | x | x | x |   |
+------------+--------------+---+---+---+---+---+---+---+---+
| Java       | retro.java   | x |   |   |   | x | x | x |   |
+------------+--------------+---+---+---+---+---+---+---+---+
| Lua        | retro.lua    | x |   |   |   | x | x | x |   |
+------------+--------------+---+---+---+---+---+---+---+---+
| Perl       | retro.pl     | x |   |   |   | x | x | x |   |
+------------+--------------+---+---+---+---+---+---+---+---+
| Python     | retro.py     | x | x | x | x | x | x | x | x |
+------------+--------------+---+---+---+---+---+---+---+---+
| Retro      | retro.rx     | x | x | x | x | x | x | x | x |
+------------+--------------+---+---+---+---+---+---+---+---+
| Ruby       | retro.rb     | x | x | x | x | x | x | x | x |
+------------+--------------+---+---+---+---+---+---+---+---+
| JavaScript | web/*        | x |   |   |   | x |   |   |   |
+------------+--------------+---+---+---+---+---+---+---+---+

A) save image
B) **include**, **:include**, **needs**
C) file i/o
D) **getEnv**
E) **time**
F) passes core test suite
G) passes vocab test suite
H) passes file io test suite


---------------------------------
Notes on Specific Implementations
---------------------------------

C
=
The C implementation can be built to support use of 16-bit,
32-bit, or 64-bit images. The default is to build for standard
32-bit images.

To build for 16-bit, define **RX16**, and for 64-bit, define
**RX64**. To actually get a 16-bit or 64-bit image, do:

::

  make tools
  ./convert


Forth
=====
The Forth VM is more of a virtualizer than an actual
virtual machine. It maps the image to the host memory,
and uses the standard Forth data stack and some native
functions. As such it needs to be used with an image
that matches your Forth's cell size.

There is no support for **getEnv** due to lack of a
standard function to access this in ANS Forth.

You can build 16-bit and 64-bit images using the
*convert* tool.


Lua
===
The Lua implementation requires Lua JIT *or* Lua 5.2.
Earlier releases of Lua lack the bitwise operators. Note
that a single line needs to be altered in the source to
enable use under Lua 5.2.


JavaScript
==========
This implementation does not support **include**, **needs**,
**getEnv**, or the **files'** vocabulary. The scripts used
to build the retroImage.js now hide these functions.


----------------------------
Experimental Implementations
----------------------------
These are all either non-standard in some way or remain mostly untested in
real-world applications.

+----------+-------------------+------------------------------------------+
| Language | File(s)           | Description                              |
+==========+===================+==========================================+
| C        | retro-dynamic.c   | Provides command line flags for altering |
|          |                   | stack depth and memory size              |
+----------+-------------------+------------------------------------------+
| C        | retro16-mbed/     | 16-bit Ngaro implementation for mbed     |
|          |                   | microcontroller                          |
+----------+-------------------+------------------------------------------+
| C        | sdl/              | SDL 1.3 based Ngaro w/support for canvas |
+----------+-------------------+------------------------------------------+
| Python   | retro-skinless.py | Python implementation w/o file I/O for   |
|          |                   | use in testing the ShedSkin compiler     |
+----------+-------------------+------------------------------------------+