Websys

[iceiix]

Now that graphics are implemented on top of glow (#262), support using WebGL through glow

Replace context creation through glutin with glow, when running on the web (keep using glutin for native). This fixes #171 failed to resolve: could not find Context in platform_impl

Replace stdweb with web-sys, since stdweb is unsupported and web-sys is more complete. Remove the std_or_web wrapper and localstoragefs because they depend on stdweb, will need to be rethought.

This does not complete the web port (still doesn't run), but it gets closer

[iceiix]

cargo web start --target wasm32-unknown-unknown now successfully compiles, while retaining native compatibility, but it fails to run:

[Log] Error loading Rust wasm module 'stevenarella': (stevenarella.js, line 46)
TypeError: import __wbindgen_placeholder__:__wbindgen_object_drop_ref must be an object
[Error] Unhandled Promise Rejection: TypeError: import __wbindgen_placeholder__:__wbindgen_object_drop_ref must be an object
	(anonymous function) (stevenarella.js:47)
	promiseReactionJob

I think I'm missing a step. Lots of different ways to do this, in flux. The example at https://github.com/grovesNL/glow/tree/main/examples/hello says to run with:

cargo build --target wasm32-unknown-unknown
mkdir -p generated
wasm-bindgen ../../target/wasm32-unknown-unknown/debug/hello.wasm --out-dir generated --target web
cp index.html generated

This fails on the first step, with a different error (even though cargo web start succeeds):

rror: entry symbol `main` declared multiple times
   --> src/main.rs:222:9
    |
222 |         pub fn main() { main2(); }
    |         ^^^^^^^^^^^^^
    |
    = help: did you use `#[no_mangle]` on `fn main`? Use `#[start]` instead

error: aborting due to previous error; 41 warnings emitted

error: could not compile `stevenarella`

despite the cfg_if! on #[cfg(target_arch = "wasm32")]...and trying to add #[start] says it is experimental/unstable. Something different than building with cargo web start.

And I used to build with wasm-pack, but removed it in 472208c since cargo web start got further, time to revisit it? Errors previously seen: #171 (comment). No longer occur, wasm-pack build succeeds:

warning: 41 warnings emitted

    Finished release [optimized] target(s) in 1m 25s
[INFO]: ⬇️  Installing wasm-bindgen...
[INFO]: ✨   Done in 1m 27s
[INFO]: 📦   Your wasm pkg is ready to publish at ./pkg.

Guides:

• https://rustwasm.github.io/docs/wasm-bindgen/
• https://rustwasm.github.io/docs/wasm-pack/
• https://github.com/rustwasm/create-wasm-app

[iceiix]

        let mut file = BufWriter::new(fs::File::create("conf.cfg").unwrap());

conditionally-compiling out, next failure is in threading (but called from where?)

[Error] panicked at 'failed to spawn thread: Custom { kind: Other, error: "operation not supported on this platform" }', /rustc/7eac88abb2e57e752f3302f02be5f3ce3d7adfb4/library/std/src/thread/mod.rs:610:29

Stack:

__wbg_new_59cb74e423758ede
__wbg_new_59cb74e423758ede@http://localhost:8080/bootstrap.js:71:106
wasm-stub@[wasm code]
<?>.wasm-function[1018]@[wasm code]
<?>.wasm-function[3391]@[wasm code]
<?>.wasm-function[1841]@[wasm code]
<?>.wasm-function[2836]@[wasm code]
<?>.wasm-function[2856]@[wasm code]
<?>.wasm-function[2773]@[wasm code]
<?>.wasm-function[2857]@[wasm code]
<?>.wasm-function[2278]@[wasm code]
<?>.wasm-function[1150]@[wasm code]
<?>.wasm-function[218]@[wasm code]
<?>.wasm-function[203]@[wasm code]
<?>.wasm-function[3420]@[wasm code]
wasm-stub@[wasm code]
main@[native code]
eval code
eval@[native code]
./index.js@http://localhost:8080/0.bootstrap.js:34:5
__webpack_require__@http://localhost:8080/bootstrap.js:603:34
__webpack_require__@[native code]
promiseReactionJob@[native code]


	__wbg_error_4bb6c2a97407129a (stevenarella_bg.js:492)
	__wbg_error_4bb6c2a97407129a (bootstrap.js:77:109)
	wasm-stub
	<?>.wasm-function[1018]
	<?>.wasm-function[3391]
	<?>.wasm-function[1841]
	<?>.wasm-function[2836]
	<?>.wasm-function[2856]
	<?>.wasm-function[2773]
	<?>.wasm-function[2857]
	<?>.wasm-function[2278]
	<?>.wasm-function[1150]
	<?>.wasm-function[218]
	<?>.wasm-function[203]
	<?>.wasm-function[3420]
	wasm-stub
	main
	Eval Code (index.js:5)
	eval
	./index.js (0.bootstrap.js:34)
	__webpack_require__ (bootstrap.js:603)
	__webpack_require__
	promiseReactionJob

[iceiix]

Restoring std_or_web until there is something better, current failure:

Panic error message: – "attempted to leave type webcore::serialization::SerializedValue uninitialized, which is invalid"
Panic location: – "/rustc/7eac88abb2e57e752f3302f02be5f3ce3d7adfb4/library/core/src/mem/mod.rs:658"
[Error] Error importing index.js: – RuntimeError: Unreachable code should not be executed (evaluating 'pkg_stevenarella_bg_wasm__WEBPACK_IMPORTED_MODULE_0_"main"')

What is this core/src/mem/mod.rs:658? If this is the right version of the library, https://github.com/rust-lang/rust/blob/master/library/core/src/mem/mod.rs#L658:

pub unsafe fn uninitialized<T>() -> T {
    // SAFETY: the caller must guarantee that an unitialized value is valid for `T`.
    unsafe {
        intrinsics::assert_uninit_valid::<T>();
        MaybeUninit::uninit().assume_init()
    }

What is webcore::serialization::SerializedValue? Looks like it is in our old friend stdweb: https://docs.rs/stdweb/0.4.20/src/stdweb/webcore/value.rs.html

Building with wasm-pack build --dev confirms:

[Error] Panic error message: – "attempted to leave type `webcore::serialization::SerializedValue` uninitialized, which is invalid"
	__cargo_web_snippet_97495987af1720d8a9a923fa4683a7b683e3acd6 (inline626.js:3:103)
	(anonymous function) (stevenarella_bg.js:1403:153)
	(anonymous function) (stevenarella_bg.js:442)
	__wbg_cargowebsnippet97495987af1720d8a9a923fa4683a7b683e3acd6_a438202dc16f44c0 (bootstrap.js:572:159)
	wasm-stub
	<?>.wasm-function[stdweb::webcore::initialization::initialize::{{closure}}::snippet::__cargo_web_snippet_97495987af1720d8a9a923fa4683a7b683e3acd6::__cargo_web_snippet_97495987af1720d8a9a923fa4683a7b683e3acd6::h3dabe35974c7b3b2]
	<?>.wasm-function[stdweb::webcore::initialization::initialize::{{closure}}::snippet::__cargo_web_snippet_97495987af1720d8a9a923fa4683a7b683e3acd6::h3f9a9f88e54c64ed]
	<?>.wasm-function[stdweb::webcore::initialization::initialize::{{closure}}::snippet::h99e107659947e789]
	<?>.wasm-function[stdweb::webcore::initialization::initialize::{{closure}}::hed8770302786655d]
	<?>.wasm-function[std::panicking::rust_panic_with_hook::hc5713da015ebaa19]
	<?>.wasm-function[std::panicking::begin_panic_handler::{{closure}}::hc5eba7f0030e8f4f]
	<?>.wasm-function[std::sys_common::backtrace::__rust_end_short_backtrace::he811f0bd07938b42]
	<?>.wasm-function[rust_begin_unwind]
	<?>.wasm-function[core::panicking::panic_fmt::h775d5c012939dd41]
	<?>.wasm-function[core::panicking::panic::hf103660e9eaae571]
	<?>.wasm-function[<stdweb::webcore::serialization::SerializedValue as core::convert::From<stdweb::webcore::serialization::SerializedUntaggedReference>>::from::he6fa71027b6660de]
	<?>.wasm-function[<T as core::convert::Into<U>>::into::hf946dfd05fbc24ce]
	<?>.wasm-function[<stdweb::webcore::value::Reference as stdweb::webcore::serialization::JsSerialize>::_into_js::h38561bb79fb71fed]
	<?>.wasm-function[<&T as stdweb::webcore::serialization::JsSerialize>::_into_js::h95d26001fd95b648]
	<?>.wasm-function[<stdweb::webcore::newtype::Newtype<(stdweb::webcore::serialization::NonFunctionTag,()),T> as stdweb::webcore::serialization::JsSerializeOwned>::into_js_owned::h4807e99c2bc80c72]
	<?>.wasm-function[stdweb::webapi::window::Window::local_storage::hfcd2d0713ee243fb]
	<?>.wasm-function[localstoragefs::fs::File::open::h526a646c80a81590]
	<?>.wasm-function[stevenarella::console::Vars::load_config::h585808260ef40191]
	<?>.wasm-function[stevenarella::main2::heddadd9feacdeaa9]
	<?>.wasm-function[stevenarella::main::ha395fada26a8133c]
	<?>.wasm-function[main]
	wasm-stub
	main
	Eval Code
	eval
	./index.js (0.bootstrap.js:118)
	__webpack_require__ (bootstrap.js:651)
	__webpack_require__
	promiseReactionJob

---

After removing localstoragefs since it requires stdweb, and replacing std_or_web with a stubbed-out File, we are back to the original Thread error:

[Info] [WDS] Live Reloading enabled.
[Info] [main.rs:240][INFO] Starting steven
panicked at 'failed to spawn thread: Custom { kind: Other, error: "operation not supported on this platform" }', /rustc/7eac88abb2e57e752f3302f02be5f3ce3d7adfb4/library/std/src/thread/mod.rs:610:29

Stack:

__wbg_new_59cb74e423758ede@http://localhost:8080/bootstrap.js:74:106
wasm-stub@[wasm code]
<?>.wasm-function[console_error_panic_hook::Error::new::h07bd190f3f82f830]@[wasm code]
<?>.wasm-function[console_error_panic_hook::hook_impl::h1bacdd9e2d2e7801]@[wasm code]
<?>.wasm-function[console_error_panic_hook::hook::h67ae4e7ff7237ec9]@[wasm code]
<?>.wasm-function[core::ops::function::Fn::call::h4a70a8d50c1533af]@[wasm code]
<?>.wasm-function[std::panicking::rust_panic_with_hook::hc5713da015ebaa19]@[wasm code]
<?>.wasm-function[std::panicking::begin_panic_handler::{{closure}}::hc5eba7f0030e8f4f]@[wasm code]
<?>.wasm-function[std::sys_common::backtrace::__rust_end_short_backtrace::he811f0bd07938b42]@[wasm code]
<?>.wasm-function[rust_begin_unwind]@[wasm code]
<?>.wasm-function[core::panicking::panic_fmt::h775d5c012939dd41]@[wasm code]
<?>.wasm-function[core::option::expect_none_failed::h924688d051ea0ca4]@[wasm code]
<?>.wasm-function[core::result::Result<T,E>::expect::h9743326f916308c4]@[wasm code]
<?>.wasm-function[std::thread::spawn::h31e99ceb42f0aaa8]@[wasm code]
<?>.wasm-function[stevenarella::render::TextureManager::new::h98124d7a66d6d1ce]@[wasm code]
<?>.wasm-function[stevenarella::render::Renderer::new::h4ced0273e291dcfa]@[wasm code]
<?>.wasm-function[stevenarella::main2::heddadd9feacdeaa9]@[wasm code]
<?>.wasm-function[stevenarella::main::ha395fada26a8133c]@[wasm code]
<?>.wasm-function[main]@[wasm code]
wasm-stub@[wasm code]
main@[native code]
eval code
eval@[native code]
./index.js@http://localhost:8080/0.bootstrap.js:34:5
__webpack_require__@http://localhost:8080/bootstrap.js:621:34
__webpack_require__@[native code]
promiseReactionJob@[native code]

skin thread:

impl TextureManager {
    fn new(
        res: Arc<RwLock<resources::Manager>>,
    ) -> (
        TextureManager,
        mpsc::Sender<String>,
        mpsc::Receiver<(String, Option<image::DynamicImage>)>,
    ) {
        let (tx, rx) = mpsc::channel();
        let (stx, srx) = mpsc::channel();
        let skin_thread = thread::spawn(|| Self::process_skins(srx, tx));

After disabling the skin thread, the errors get more interesting:

[iceiix]

Updating to support #version 300 es GLSL (WebGL 2 / OpenGL ES 3), in addition to the #version 150 (OpenGL 3.2) we supported before (examples show #version 410 = OpenGL 4.1 but we're not using any OpenGL 4 functionality so no need to update to OpenGL 3 yet, see https://en.wikipedia.org/wiki/OpenGL_Shading_Language).

The current error is related to accum and revealage outputs in src/render/shaders/chunk_frag.glsl:

[Error] WebGL: ERROR: 0:16: 'accum' : must explicitly specify all locations when using multiple fragment outputs
[Error] WebGL: ERROR: 0:17: 'revealage' : must explicitly specify all locations when using multiple fragment outputs
[Error] [render/shaders.rs:150][ERROR] Src: #version 300 es
precision mediump float;
precision mediump sampler2DArray;
#define alpha
uniform sampler2DArray textures;

in vec3 vColor;
in vec4 vTextureInfo;
in vec2 vTextureOffset;
in float vAtlas;
in vec3 vLighting;

#ifndef alpha
out vec4 fragColor;
#else
out vec4 accum;
out float revealage;
#endif

const float invAtlasSize = 1.0 / 1024.0;
vec4 atlasTexture() {
    vec2 tPos = vTextureOffset;
    tPos = clamp(tPos, vec2(0.1), vTextureInfo.zw - 0.1);
    tPos += vTextureInfo.xy;
    tPos *= invAtlasSize;
    return texture(textures, vec3(tPos, vAtlas));
}

void main() {
    vec4 col = atlasTexture();
    #ifndef alpha
    if (col.a < 0.5) discard;
    #endif
    col *= vec4(vColor, 1.0);
    col.rgb *= vLighting;

    #ifndef alpha
    fragColor = col;
    #else
    float z = gl_FragCoord.z;
    float al = col.a;
    float weight = pow(al + 0.01f, 4.0f) +
                     max(0.01f, min(3000.0f, 0.3f / (0.00001f + pow(abs(z) / 800.0f, 4.0f))));
    accum = vec4(col.rgb * al * weight, al);
    revealage = weight * al;
    #endif
}

Useful articles: https://webgl2fundamentals.org/webgl/lessons/webgl1-to-webgl2.html and https://webgl2fundamentals.org/webgl/lessons/webgl2-whats-new.html, in particular, WebGL2 is more on par with what this project needs (it uses vertex arrays, etc., now always available in WebGL2 unlike WebGL1)

[iceiix]

https://www.khronos.org/opengl/wiki/Fragment_Shader#Outputs

Now gets as far as hitting the multisample sample in src/render/shaders/trans_frag.glsl:

[main.rs:240][INFO] Starting steven
[main.rs:335][INFO] Shader version: #version 300 es
WebGL: ERROR: 0:7: 'sampler2DMS' : Illegal use of reserved word
WebGL: ERROR: 0:7: 'sampler2DMS' : syntax error
[render/shaders.rs:150][ERROR] Src: #version 300 es
...
uniform sampler2D taccum;
uniform sampler2D trevealage;
uniform sampler2DMS tcolor;

sample2DMS will have to be removed/replaced, but it is non-trivial: #442 renderbuffer

[iceiix]

Since further progress is hitting a blocker (#442), but this is a useful step towards web support, will merge this to master. Opened a new issue for the overall effort: #446 🕸️ Web support