Update documentation

docs/src/development-guide/how-to-run.md

@@ -102,18 +102,35 @@ click on run. This will start the MacOS application.
 
 ## Web (WebGL, WebGPU)
 
-If you have a browser which already supports a recent version of the WebGPU specification then you can start a
-development server using the following commands.
+You need to first build the library for WebGL or WebGPU. Optionally, you can also enabled multi-threading support,
+which requires that the library is used in a secure environment: 
+[isSecureContext](https://developer.mozilla.org/en-US/docs/Web/API/isSecureContext)
+and [crossOriginIsolated](https://developer.mozilla.org/en-US/docs/Web/API/crossOriginIsolated). 
+The demo runs this such an environment.
+
+If you have a browser which already supports a recent version of the WebGPU specification then you can build the library
+with WebGPU:
 
 ```bash
-cd web
-npm run start
+just web-lib build # WebGPU
 ```
 
-If you want to run maplibre-rs with WebGL which is supported on every major browser, then you have to use the following
-command.
+If not, then you must enable WebGL support:
+
+
+```bash
+just web-lib build --webgl # WebGL
+just web-lib build --webgl --multithreaded # WebGL + multithreaded
+```
+
+Instead of building it is also possible to watch for changes. The same flags like with `web-lib build` are supported:
+
+```bash
+just web-lib watch --webgl
+```
+
+After building the library you can run the demo server:
 
 ```bash
-just web-lib build
 just web-demo start
 ```

web/lib/src/worker-types.ts

@@ -1,9 +0,0 @@
-export type WebWorkerMessageType = {
-    type: 'init',
-    memory: WebAssembly.Memory
-} | {
-    type: 'fetch_tile',
-    threadLocalState: number,
-    url: string,
-    request_id: number,
-}

web/src/platform/singlethreaded/apc.rs

@@ -63,15 +63,15 @@ impl SerializedMessageTag {
 }
 
 trait SerializableMessage {
-    fn serialize(self) -> &[u8];
+    fn serialize(&self) -> &[u8];
 
-    fn deserialize(tag: SerializedMessageTag, data: &[u8]) -> Message<UsedTransferables>;
+    fn deserialize(tag: SerializedMessageTag, data: Uint8Array) -> Message<UsedTransferables>;
 
-    fn tag(&self) -> u32;
+    fn tag(&self) -> SerializedMessageTag;
 }
 
-impl<T: Transferables> SerializableMessage for Message<T> {
-    fn serialize(self) -> &[u8] {
+impl SerializableMessage for Message<LinearTransferables> {
+    fn serialize(&self) -> &[u8] {
         match self {
             Message::TileTessellated(data) => bytemuck::bytes_of(data),
             Message::UnavailableLayer(data) => bytemuck::bytes_of(data),
@@ -79,7 +79,7 @@ impl<T: Transferables> SerializableMessage for Message<T> {
         }
     }
 
-    fn deserialize(tag: SerializedMessageTag, data: &[u8]) -> Message<UsedTransferables> {
+    fn deserialize(tag: SerializedMessageTag, data: Uint8Array) -> Message<UsedTransferables> {
         match tag {
             SerializedMessageTag::TileTessellated => {
                 Message::<UsedTransferables>::TileTessellated(*bytemuck::from_bytes::<
@@ -121,6 +121,9 @@ pub struct PassingContext {
 
 impl Context<UsedTransferables, UsedHttpClient> for PassingContext {
     fn send(&self, data: Message<UsedTransferables>) {
+        let tag = data.tag();
+        let serialized = data.serialize();
+
         let serialized_array_buffer = js_sys::ArrayBuffer::new(serialized.len() as u32);
         let serialized_array = js_sys::Uint8Array::new(&serialized_array_buffer);
         unsafe {
@@ -129,8 +132,8 @@ impl Context<UsedTransferables, UsedHttpClient> for PassingContext {
 
         let global = js_sys::global().unchecked_into::<DedicatedWorkerGlobalScope>(); // FIXME (wasm-executor): Remove unchecked
         let array = js_sys::Array::new();
-        array.push(&JsValue::from(data.tag() as u32));
-        array.push(&data.serialize());
+        array.push(&JsValue::from(tag as u32));
+        array.push(&serialized_array_buffer);
         global.post_message(&array).unwrap(); // FIXME (wasm-executor) Remove unwrap
     }