Scaffold vpinball-wasm: Emscripten port of Visual Pinball

Build scripts, CMake/source patches, npm packaging, and a Gitea CI workflow to compile the real Visual Pinball engine (SDL3 + WebGL2 + libwinevbs for real VBScript) to WebAssembly. The patches are validated end-to-end: the patched engine boots in a real browser, loads a real .vpx table, compiles its real GLSL shaders, computes environment map radiance, initializes physics, and starts the VBScript engine, before hanging on the one deliberately-deferred piece of work (game loop rewrite around emscripten_set_main_loop), documented in the README's roadmap.
2026-08-22 14:30:14 +02:00
commit 0a63835689
18 changed files with 1151 additions and 0 deletions
@@ -0,0 +1,47 @@
+--- a/third-party/include/ThreadPool.h
+++ b/third-party/include/ThreadPool.h
+@@ -110,9 +110,20 @@
+     : pool_size(threads)
+     , in_flight(0)
+ {
+#ifndef __EMSCRIPTEN__
+     const std::unique_lock<std::mutex> lock(this->queue_mutex);
+     for (std::size_t i = 0; i != threads; ++i)
+         start_worker(i, lock);
+#else
+    // vpinball-wasm: a single-threaded Emscripten build (no -pthread /
+    // SharedArrayBuffer for v1) cannot construct real std::thread workers -
+    // std::thread's constructor throws at runtime otherwise ("thread
+    // constructor failed"). Run zero real workers; enqueue() below executes
+    // tasks synchronously and inline instead, matching the porting plan's
+    // "run ThreadPool work serially" decision for one-off parallel work
+    // (parallel .vpx item deserialization at load, env-map baking, etc.).
+    (void)pool_size;
+#endif
+ }
+ 
+ // add new work item to the pool
+@@ -139,6 +150,15 @@
+ 
+     std::future<return_type> res = task->get_future();
+ 
+#ifdef __EMSCRIPTEN__
+    // vpinball-wasm: no real worker threads exist (see the constructor) -
+    // run the task synchronously inline so callers still get a valid,
+    // already-ready future, exactly as if it had run on a worker.
+    (void)std::atomic_fetch_add_explicit(&in_flight, std::size_t(1), std::memory_order_relaxed);
+    (*task)();
+    (void)std::atomic_fetch_sub_explicit(&in_flight, std::size_t(1), std::memory_order_acq_rel);
+    return res;
+#else
+     std::unique_lock<std::mutex> lock(queue_mutex);
+     if (tasks.size () >= max_queue_size)
+         // wait for the queue to empty or be stopped
+@@ -160,6 +180,7 @@
+     condition_consumers.notify_one();
+ 
+     return res;
+#endif
+ }
+ 
+