Versatile Commodore Emulator for JavaScript
JavaScript port of VICE 2.4 using Emscripten.
| Browser | Version | Status | Note |
|---|---|---|---|
| Firefox | 39 | :) | ok |
| Chrome | 43 | : | |
| IE | 11 | :( | broken |
###c64 basic
<!doctype html>
<html lang="en-us">
<body>
<!-- the canvas *must not* have any border or padding, or mouse coords will be wrong -->
<canvas id="canvas" style="border: 0px none;"></canvas>
<script type="text/javascript" >
var Module = {
arguments: ['+sound'],
canvas: document.getElementById('canvas'),
};
</script>
<script type="text/javascript" src="js/x64.js"></script>
</body>
</html><!doctype html>
<html lang="en-us">
<body>
<!-- the canvas *must not* have any border or padding, or mouse coords will be wrong -->
<canvas id="canvas" style="border: 0px none;"></canvas>
<script type="text/javascript" >
function audioDetected() {
return (typeof Audio === 'function' && new Audio().mozSetup === 'function') ||
(typeof AudioContext === 'function') ||
(typeof webkitAudioContext === 'function');
}
function loadFiles() {
var base64EncodedFile = '...';
FS.createDataFile('/', 'disk-image.d64', window.atob(base64EncodedFile), true, true);
}
var viceArguments = ['-autostart', 'disk-image.d64'].concat(
audioDetected() ? ['-soundsync', 0, '-soundrate', 22050, '-soundfragsize', 2] : ['-sound']
);
var Module = {
preRun: [loadFiles],
arguments: viceArguments,
canvas: document.getElementById('canvas'),
};
</script>
<script type="text/javascript" src="js/x64.js"></script>
</body>
</html><!doctype html>
<html lang="en-us">
<body>
<!-- the canvas *must not* have any border or padding, or mouse coords will be wrong -->
<canvas id="canvas" style="border: 0px none;"></canvas>
<p><button onmousedown="sendSpaceKeyPressedCode()" onmouseup="sendSpaceKeyReleasedCode()">space bar</button></p>
<script type="text/javascript" >
var C64_SPACE_KEY_CODE = 32;
function sendSpaceKeyPressedCode() {
Module.ccall('keyboard_key_pressed', 'undefined', ['number'], [C64_SPACE_KEY_CODE]);
}
function sendSpaceKeyReleasedCode() {
Module.ccall('keyboard_key_released', 'undefined', ['number'], [C64_SPACE_KEY_CODE]);
}
var Module = {
arguments: ['+sound'],
canvas: document.getElementById('canvas'),
};
</script>
<script type="text/javascript" src="js/x64.js"></script>
</body>
</html>async mode:
- soundfragsize 2 -soundrate 22050 -soundsync 0
sync mode:
- soundfragsize 2 -soundrate 22050 -soundsync 0 -ntsc
- ntsc is important because browser requestAnimationFame is going to deliver 60 fps which means less cpu time is wasted during vsync delay
###How to find key codes
- in
/vice/src/arch/sdl/kbd.c # sdlkbd_press() - this line prints key codes to console when key is pressed
fprintf(stderr, "%s: %i (%s),%i\n",__func__,key,SDL_GetKeyName(key),mod);- activate by compiling vice with SDL_DEBUG flag
C64 Wiki
Commodore 64 keyboard matrix layout
COMMODORE 64 ROGRAMMER'S REFERENCE GUIDE
Commodore Manuals
Coroutines in C
requestAnimationFrame setting fps
SDL 1.2 to 2.0 Migration Guide
VICE Manual
VICE options
- try using worker thread (emcc --proxy-to-worker)
- initial tests show +10% perf in Chrome, but missing SDL Audio
- discuss proxy-to-worker
- discuss web audio & web workers
- nice callback pattern for web workers
- Proxy SDL Audio
- \vice\src\sounddrv\soundsdl.c
- \emscripten\src\library_sdl.js
- line 1636 creates Audio object
- \emscripten\src\proxyWorker.js
- \emscripten\src\proxyClient.js
- Native audio classes shim proxy option: Create proxies for each Audio class and simply define these classes in proxyWorker.js.
- proxyClient will feature detect available Audio classes and send this info the proxyWorker
- proxyWorker will implement Audio classes based on features detected by proxyClient
- Conclusions
- A large API needs to be proxied, lots of different Classes some vary by browser.
- Managing all the audio object proxies (createBufferSource, createBuffer) is complicated.
- Need to track references to proxied objects.
- Determining when to free objects can be difficult.
postMessagecommunication would be chatty.
- Proxy SDL_*Audio C functions
- Seperate C code from Web Audio API's
- Re-factor
pushAudiofunction to use data arrays instead of a pointer to heap
- Re-factor
- Copy Web Audio parts of SDL_*Audio functions to proxyClient
- Detect proxyClient in library_sdl and invoke proxy versions of SDL_*Audio functions
- Conclusions
- Code duplication, some code from SDL_*Audio functions exist in both library_sdl and proxyClient
- extra data copy required by pushAudio function
- current process
- copy data from heap directly into Web Audio buffers $expensive
- new worker process
- copy data from heap into ArrayBuffer $expensive
- transfer ownership of data to browser thread
- copy data into Web Audio buffers $expensive
- current process
- Issues
- SDL init is synchronous so if there's a problem in the browser context part, worker does not know.
- Possible solution is to feature detect Web Audio and send the info to worker ahead of time so it can make a better SDL init process.
- Sound buffer overflows if tab goes to background, probably caused by request animation frame slowing down browser thread but worker is still at full speed.
- Sound clicks, weird timing
- SDL init is synchronous so if there's a problem in the browser context part, worker does not know.
- Use
function addRunDependency(id)instead of customwaitForAudioFeatureslogic. - Test with \emscripten\tests\sdl_audio_beep.cpp
- ./emcc -O2 --minify 0 -s DISABLE_EXCEPTION_CATCHING=0 -o audio-beep.html --proxy-to-worker --closure 1 tests/sdl_audio_beep.cpp
- proxy-dependency-bug
- ./emcc tests/hello_world_sdl.cpp -o hello.html --proxy-to-worker --post-js hello_world_dependencies.js
- Seperate C code from Web Audio API's
- file issue for Emscripten with patch
- Chrome has a
consolein web worker context so detect it before over-writing @ proxyWorker.js line ~81
- Chrome has a
self.console = self.console || {
log: function(x) {
Module.printErr(x);
}
};
- add other computers
- VIC-20
- fix vice menu ui (F12)