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<!DOCTYPE html>
<html style="height: 100%; overflow: hidden; overflow-x: hidden;">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width,initial-scale=1">
<link rel='icon' type='image/gif' href='/favicon.gif'>
<title> Reduced System Layer </title>
</head>
<body style="margin: 0; height: 100%; overflow: hidden; overflow-x: hidden;">
<canvas style="margin: 0; width: 100%; height: 100%;" id="frame" oncontextmenu="event.preventDefault()"></canvas>
<script type="text/javascript">
function string_from_memory(bytes, offset) {
let len = 0;
while (bytes[offset + len] != 0)
++len;
return new TextDecoder("utf8").decode(bytes.subarray(offset, offset + len));
}
async function run(attrs) {
let wait_for_events = false;
let sleep_duration = 0;
let canvas;
let program;
let memory;
let pixels_address;
let context;
let animation_frame;
canvas = document.getElementById(attrs.id);
context = canvas.getContext("2d");
program = await WebAssembly.instantiateStreaming(
fetch("index.wasm"),
{
"wasi_snapshot_preview1" : {
clock_time_get : () => { return Date.now(); },
args_sizes_get : () => { throw new Error("Unexpected args_sizes_get call"); },
args_get : () => { throw new Error("Unexpected args_get call"); },
proc_exit : () => { throw new Error("Unexpected proc_exit call"); },
fd_close : () => { throw new Error("Unexpected fd_close call"); },
fd_write : () => { throw new Error("Unexpected fd_write call"); },
fd_seek : () => { throw new Error("Unexpected fd_seek call"); },
},
"env" : {
p_init : () => {
program.instance.exports.js_init();
memory = new Uint8Array(program.instance.exports.memory.buffer);
pixels_address = program.instance.exports.js_pixels();
document.title = string_from_memory(memory, program.instance.exports.js_title());
},
p_render_frame_impl : () => {
let data = new ImageData(
new Uint8ClampedArray(
memory.subarray(
pixels_address,
pixels_address + 4 * canvas.width * canvas.height
)
),
canvas.width,
canvas.height
);
context.putImageData(data, 0, 0);
},
p_clipboard_write : (size, text) => {
navigator.clipboard.writeText(
new TextDecoder().decode(memory.subarray(text, text + size))
).catch((e) => { console.error(e); });
},
p_cleanup : () => {},
p_wait_events_impl : () => { wait_for_events = true; },
p_sleep_for : (time) => { sleep_duration += time; },
p_time : Date.now,
sqrt : Math.sqrt,
floor : Math.floor,
ceil : Math.ceil,
memset : (dst, val, num) => {
program.instance.exports.js_memset(dst, val, num);
},
memcpy : (dst, src, num) => {
program.instance.exports.js_memcpy(dst, src, num);
},
},
}
);
program.instance.exports.js_main(document.location.href);
animation_frame = (time) => {
if (attrs.fit_window) {
canvas.width = window.innerWidth;
canvas.height = window.innerHeight;
}
wait_for_events = false;
program.instance.exports.js_frame(canvas.width, canvas.height);
if (!wait_for_events) {
if (sleep_duration > 0) {
let timeout = sleep_duration;
sleep_duration = 0;
setTimeout(() => {
window.requestAnimationFrame(animation_frame);
}, timeout);
} else
window.requestAnimationFrame(animation_frame);
}
};
window.addEventListener("resize", (ev) => {
window.requestAnimationFrame(animation_frame);
});
canvas.addEventListener("mousedown", (ev) => {
program.instance.exports.js_mousedown(ev.buttons);
window.requestAnimationFrame(animation_frame);
});
canvas.addEventListener("mouseup", (ev) => {
program.instance.exports.js_mouseup(ev.buttons);
window.requestAnimationFrame(animation_frame);
});
canvas.addEventListener("mousemove", (ev) => {
program.instance.exports.js_mousemove(ev.clientX, ev.clientY);
window.requestAnimationFrame(animation_frame);
});
let key_from_code = (code) => {
switch (code) {
case "KeyA": return 97;
}
return 0;
};
let mod_from_event = (ev) => {
let mod = 0;
if (ev.ctrlKey) mod |= 1;
if (ev.shiftKey) mod |= 2;
if (ev.altKey) mod |= 4;
if (ev.metaKey) mod |= 8;
return mod;
};
window.addEventListener("keydown", (ev) => {
ev.preventDefault();
if (!ev.repeat) {
let mod = mod_from_event(ev);
let key = key_from_code(ev.code);
if (key != 0)
program.instance.exports.js_keydown(key, mod);
window.requestAnimationFrame(animation_frame);
}
});
window.addEventListener("keyup", (ev) => {
ev.preventDefault();
if (!ev.repeat) {
let mod = mod_from_event(ev);
let key = key_from_code(ev.code);
if (key != 0)
program.instance.exports.js_keyup(key, mod);
window.requestAnimationFrame(animation_frame);
}
});
window.requestAnimationFrame(animation_frame);
}
run({
id : "frame",
fit_window : true,
}).catch((e) => console.error(e));
</script>
</body>
</html>
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