Pixel Script

A multi language scripting runtime built in Rust.

PixelScript lets you expose the same API to multiple different languages in your program. Because it compiles to a C library, you can use it anywhere.

Why PixelScript?

Because most games pick only one language for scripting. PixelScript gives modders and scripters a choice:

• Performance? Go with Lua.
• Data/science/prototyping? Choose Python.
• Web developers? You got JavaScript.
• Love easyjs? You got it!

Each language runtime uses the same PixelScript bindings.

Version

pixelscript crate is currently at version 0.2.0.

How to use

To use Pixel Script, you will have to clone this repository. When compiling, if you only want a specific language you will have to set --no-default-features and --features "<language1>,<language2>". If you want to compile for all languages simply run the build script under scripts/ It will compile the library and place the files under /pxsb.

For rust based use I will be adding a Rust wrapper, which is funny because this is written in Rust. But I want all systems that use the pixelscript library (rust included) to use the low level bindings. Which means I will write a High level and safe rust bindings. Until then, hack it using FFI.

Supported languages

Feature flag	Language	Engine	Notes
lua	Lua	mlua	Fast, battle-tested, v5.4
python	Python	pocketpy	Requires MSVC on Windows
js	JavaScript	rquickjs	Quickjs, C library
easyjs	EasyJS	easyjsc	Requires a JS feature
php	PHP	PH7	Only supports v5.3 and the engine is not maintained anymore
rustpython	Python (CPython compatible)	rustpython	Larger binary, Full Python library support, currently leaking memory.

When including easyjs make sure to also include a JavaScript feature otherwise it will not work.

CoreLib

To include the PixelScript core API, add the include-core feature.

Module name	Module purpose	Languages Type	Notes
ps_json	Adds JSON encoding, decoding, and .* properties.	Lua(Tree), Python(object), JS(Prototype), easyjs(struct)	Requires a loader function. Set via pxs_set_file_reader and a writer function via pxs_set_file_writer

Building

In order to use pixelscript, you need to first compile it's libraries. Each language could potentially have it's own libraries. Each library will be fetched and placed under a pxsb folder in the main directory of your build system.

To build simply run:

cargo build --release

On your rust crate. This will build the pixelscript library and make all language libs accessible.

Example

Here is a "Hello World" example supporting Lua, Python, PHP, JavaScript, and easyjs.

#include "pixelscript.h"
// Optional macros (for C/C++ codespaces)
#include "pixelscript_m.h"

// One with the macro
PXS_HANDLER(mprintln) {
    pxs_VarT contents_var = PXS_ARG(1);
    char* contents_str = pxs_getstring(contents_var);

    printf("%s", contents_str);

    // Free the string
    pxs_freestr(contents_str);
}

// One without the macro
pxs_VarT println(pxs_VarT args, pxs_Opaque opaque) {
    // Get contents
    pxs_VarT contents_var = pxs_listget(args, 1);
    char* contents_str = pxs_getstring(contents_var);

    printf("%s", contents_str);

    // Free the string
    pxs_freestr(contents_str);
}

int main() {
    pxs_initialize();
    
    // Create a module
    pxs_Module* main = pxs_newmod("main");

    // Add callbacks
    pxs_addfunc(main, "mprintln", mprintln, NULL);
    pxs_addfunc(main, "println", println, NULL);

    // Lua
    const char* lua_script = "local main = require('main')\n"
        "main.print('Hello World from Lua!')";
    char* error = pxs_execlua(lua_script, "<ctest>");
    pxs_freestr(error);

    // Python
    const char* python_script = "import main\n"
                                "main.print('Hello World from Python')\n";

    char* error = pxs_execpython(python_script, "<ctest>");
    pxs_freestr(error);

    // JavaScript
    const char* js_script = "import * as main from 'main';\n"
                            "main.print('Hello World from JavaScript!');";
    char* error = pxs_execjs(js_script, "<ctest>");
    pxs_freestr(error);

    // easyjs
    const char* ej_script = "import 'main'\n"
                            "main.print('Hello World from easyjs!')";
    char* error = pxs_execej(ej_script, "<ctest>");
    pxs_freestr(error);

    // PHP!!!! 
    const char* php_script = "include('main');\n" // or require
                            "\\main\\print('Hello World from PHP!');";
    char* error = pxs_execphp(php_script, "<ctest>");
    pxs_freestr(error);

    pxs_finalize();

    return 0;
}

Used in

• Pixel Ai Dash
• easyjs (runtime)

Future

This will ideally be used by all future epochtech games since it allows for modding in multiple languages. It's not quite ready to be used in production for anyone other than myself and epochtech. But if you make PRs to fix something or open issues, I will be responding and merging. Feel free to add a language, just check out /lua or /python for examples on how to use Var, Func, Module, PixelObject, and PixelScripting.

Also RustPython and Luajit do not currently work.

Made with ❤️ by @epochtechgames