oden/src/script.rs

139 lines
3.7 KiB
Rust

use oden_js::{
module::loader::{ModuleLoader, ModuleSource},
Context, ContextRef, Result, Runtime, Value,
};
use std::ffi::OsStr;
use std::sync::mpsc::{channel, Receiver};
use std::time::Instant;
pub mod graphics;
use graphics::GraphicsCommand;
mod typescript;
use typescript::transpile_to_javascript;
mod io;
mod time;
struct Loader {}
impl Loader {
pub fn new() -> Loader {
Loader {}
}
}
impl ModuleLoader for Loader {
fn load(&self, _context: &ContextRef, name: &str) -> Result<ModuleSource> {
eprintln!("Loading {name}...");
let path = io::resolve_path(name, &["ts"])?;
let contents = std::fs::read_to_string(&path)?;
let contents = if path.extension().and_then(OsStr::to_str) == Some("ts") {
transpile_to_javascript(name, contents)?
} else {
contents
};
Ok(ModuleSource::JavaScript(contents))
}
}
pub struct ScriptContext {
context: Context,
init: Value,
update: Value,
draw: Value,
gfx: graphics::GraphicsAPI,
gfx_receive: Receiver<graphics::GraphicsCommand>,
time: time::TimeAPI,
}
impl ScriptContext {
pub fn new() -> Self {
let runtime = Runtime::with_loader(Loader::new());
let mut context = Context::new(runtime);
context.add_intrinsic_bigfloat();
context.add_intrinsic_bigdecimal();
context.add_intrinsic_operators();
let (gfx_send, gfx_receive) = channel();
let gfx = graphics::GraphicsAPI::define(&context, gfx_send.clone())
.expect("Graphics module should load without error");
let _io = io::IoAPI::define(&context).expect("IO module should load without error");
let time = time::TimeAPI::define(&context).expect("Time module should load without error");
let module = context
.import_module("./main.ts", "")
.expect("Unable to load main");
let init = module
.get_export(&context, "init")
.expect("Unable to fetch init");
let update = module
.get_export(&context, "update")
.expect("Unable to fetch update");
let draw = module
.get_export(&context, "draw")
.expect("Unable to fetch draw");
ScriptContext {
context,
init,
update,
draw,
gfx,
gfx_receive,
time,
}
}
// TODO: The script could really be on a background thread you know.
// We would want a bi-directional gate for frames to not let the
// game thread go to fast probably? And to discard whole frames &c.
pub fn init(&mut self) {
self.init
.call(&self.context, &[])
.expect("Exception in init");
}
pub fn update(&mut self) {
// Do we update the frame time before of after async completion?
// Hmmmmm.
self.time.set_frame_time(Instant::now());
// Tell the runtime to process all pending "jobs". This includes
// promise completions.
self.context
.process_all_jobs()
.expect("Error processing async jobs");
// Now run the update function.
self.update
.call(&self.context, &[])
.expect("Exception in update");
}
pub fn render(&mut self) -> Vec<graphics::GraphicsCommand> {
self.draw
.call(&self.context, &[])
.expect("Exception in draw");
self.gfx.end_frame();
let mut commands = Vec::new();
loop {
match self.gfx_receive.recv().unwrap() {
GraphicsCommand::EndFrame => break,
other => commands.push(other),
}
}
commands
}
}