VICE.js ======= Versatile Commodore Emulator for JavaScript JavaScript port of VICE 2.4 using Emscripten. [Demo](http://vice.janicek.co/) [VICE](http://sourceforge.net/projects/vice-emu/) [Emscripten](https://github.com/kripken/emscripten) | Browser | Version | Status | Note | -------- | ---------- | ------ | ---- | Firefox | 39 | :) | ok | Chrome | 43 | :| | sound clicks | IE | 11 | :( | broken Examples ------- ###[c64 basic](http://rjanicek.github.io/vice.js/c64-basic.html) ```html

``` ###[auto-run a D64 disk image](http://rjanicek.github.io/vice.js/auto-run-a-D64-disk-image.html) ```html

``` ###[send keyboard commands](http://rjanicek.github.io/vice.js/c64-keyboard.html) ```html

``` Best Configuration Options -------------------------- 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 Development ----------- ###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 ```c fprintf(stderr, "%s: %i (%s),%i\n",__func__,key,SDL_GetKeyName(key),mod); ``` * activate by compiling vice with SDL_DEBUG flag Resources --------- [C64 Wiki](http://www.c64-wiki.com) [Commodore 64 keyboard matrix layout](http://sta.c64.org/cbm64kbdlay.html) [COMMODORE 64 ROGRAMMER'S REFERENCE GUIDE](http://www.c64.ch/programming/c64prg10.txt) [Commodore Manuals](http://www.commodore.ca/commodore-manuals/) [Coroutines in C](http://www.chiark.greenend.org.uk/~sgtatham/coroutines.html) [requestAnimationFrame setting fps](http://creativejs.com/resources/requestanimationframe/) [SDL 1.2 to 2.0 Migration Guide](http://wiki.libsdl.org/moin.fcg/MigrationGuide) [VICE Manual](http://www.viceteam.org/vice_toc.html) [VICE options](vice-options.md) Tasks ----- * try using worker thread (emcc --proxy-to-worker) * initial tests show +10% perf in Chrome, but missing SDL Audio * [discuss proxy-to-worker](https://groups.google.com/forum/#!searchin/emscripten-discuss/worker$20proxy/emscripten-discuss/uUbvJsM_jUU/KL-a3YPVWuoJ) * [discuss web audio & web workers](https://groups.google.com/forum/#!searchin/emscripten-discuss/web$20audio$20web$20workers/emscripten-discuss/erT7NCEeWgY/lPyK2rF_t6sJ) * [nice callback pattern for web workers](http://stackoverflow.com/questions/18056637/html5-web-worker-communication) * 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. * `postMessage` communication would be chatty. * Proxy SDL_*Audio C functions * Seperate C code from Web Audio API's * Re-factor `pushAudio` function to use data arrays instead of a pointer to heap * 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 * 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 * Use `function addRunDependency(id)` instead of custom `waitForAudioFeatures` logic. * 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 * file issue for Emscripten with patch * Chrome has a `console` in web worker context so detect it before over-writing @ proxyWorker.js line ~81 ``` self.console = self.console || { log: function(x) { Module.printErr(x); } }; ``` * add other computers * VIC-20 * fix vice menu ui (F12)