Ginja is a string template engine for Godot 4.

Provides access to (some of) Inja's features.

This is a GdExtension addon for Godot 4.

Motivation

• Generate tailored, efficient shaders.
• Generate gdscript during development.
• Generate dialogues, messages, and roleplays.
• …

Demo

If you have a bleeding edge Godot 4 (more recent than alpha9), you can download and run the demo in Releases to see an example shader generation.

This source tree holds what's needed to build the shared libraries, not the shared libraries themselves since they are binary blobs.

Usage

var tpl = "Hello, {{ name }} !"
var ginja = Ginja.new()
var msg = ginja.render(tpl, {
    'name': "Nathanaël",
})

print(msg)

This is a very simple example, but you may use loops, conditions, comments, etc. See Inja's documentation for the available features.

You may also define your own functions for use in the templates:

func _ready():
	var ginja = Ginja.new()
	ginja.add_function("repeat", 2, self, "call_repeat")
	var msg = ginja.render("{{ repeat(msg, amount) }}", {
		'msg': "🎶!",
		'amount': 5,
	})
	assert(msg == "🎶!🎶!🎶!🎶!🎶!")


func call_repeat(msg: String, amount: int) -> String:
	return msg.repeat(times)

You HAVE TO specify the amount of arguments your custom function uses.

You can also define and register variadic functions, like sum here:

func _ready():
	var ginja = Ginja.new()
	ginja.add_function_variadic("sum", self, "call_sum")
	var answer = ginja.render("{{ sum(a, b, c) }}", {
		'a': 41,
		'b': -5,
		'c': 6,
	})
	assert(answer == "42")


func call_sum(arguments: Array) -> int:
	var total := 0
	for argument in arguments:
		total += argument
	return total

Current Limitations

• LEAKING (see #1 — might not be us)
• GdNative DOES NOT WORK IN EXPORTED HTML5 BUILDS
• Single character unicode strings (like 🎶) behave oddly and yield empty strings sometimes
• No personal plans for testing Windows or Mac, contribs welcome
• Variadic user-defined functions need at least one parameter when called
• Limited to Inja capabilities. Eg: Inja offers no filters
• include and extend might not work in exported projects (to check)
• Error when fetching callback Object from its RID: (but it works)

ERROR: Condition "_instance_bindings != nullptr" is true.
   at: set_instance_binding (core/object/object.cpp:1771)

Can't figure out if it's our fault or not, for this one. Idea: try Ref<Object> instead of RID&.

Support

Unsupported in HTML5 builds, beware ! See the state of GdNative on HTML5.

• Linux x86_64
• Linux x86_32 (to test)
• Windows x86_64 (to test)
• Windows x86_32 (to test)
• Mac x86_64 (to test)
• …

Shader and gdscript generation is still useful during development, even if we can't rely on it at runtime for now.

Install

The installation is as usual, through the Assets Library. (todo)

Meanwhile, dowload the latest Release (on the right), or clone this repository and build the shared objects.

The shared libs were not added to this repository, since they are build artifacts. (CI is coming)

Then you can copy the addons/ directory of this project into yours.

Finally, enable the plugin in Scene > Project Settings > Plugins.

Build

Build the shared libraries:

cd gdextension_generator
CORES=4 TARGET=debug build.sh
CORES=4 TARGET=release build.sh

Want to do this using CI, but we need a custom action, or to find a docker image with everything we need.

Setup Dev Notes

Use homebuilt Godot 4 from master, not alpha9.

Submodules

Ideally:

git submodule add -b 4.x https://github.com/godotengine/godot-cpp gdextension_generator/godot-cpp

Pragma 'til the 4.x branch exists:

git submodule add https://github.com/godotengine/godot-cpp gdextension_generator/godot-cpp

Remember to init the submodules!

Build

The first step is always to compile the godot-cpp library:

cd gdextension_generator/godot-cpp
scons target=debug

Then we can compile our shared library:

cd gdextension_generator
scons target=debug

It outputs in the addons/goutte.template.inja/bin/ directory.

The libs are voluminous because they are not stripped, you may do so:

strip addons/goutte.template.inja/bin/libgd*

Demo

The demo uses a symlink to get as child its sibling addons/ directory. Might not hold through git across platforms, beware.

Inja

Inja has been copied from 3.3, and the #include of json have been changed to use the local file: #include "json.hpp". Both are warts, and enlightened suggestions are welcome.

Vanilla GdScript Implementation

Just thoughts on a vanilla gdscript fallback for Ginja.

ANTLR

Needs gdscript templates and runtime first. Those are 404 for now.

CUSTOM

Would allow for easier customization of the enclosing markup tokens. Much more work. Faster code, though. (if done well)