🔧

Author: wcandillon

packages/webgpu/cpp/rnwgpu/api/GPUCanvasContext.cpp

@@ -48,15 +48,36 @@ jsi::Value GPUCanvasContext::getCurrentTexture(jsi::Runtime &runtime,
   auto texture = _surfaceInfo->getCurrentTexture();
 
   auto surfaceInfo = _surfaceInfo;
-  auto present = jsi::Function::createFromHostFunction(
-      runtime, jsi::PropNameID::forAscii(runtime, "WebGPUPresent"), 0,
-      [surfaceInfo](jsi::Runtime & /*rt*/, const jsi::Value & /*thisValue*/,
-                    const jsi::Value * /*args*/,
-                    size_t /*count*/) -> jsi::Value {
-        surfaceInfo->present();
-        return jsi::Value::undefined();
-      });
-  runtime.queueMicrotask(std::move(present));
+  auto presentCb = [surfaceInfo](jsi::Runtime & /*rt*/,
+                                 const jsi::Value & /*thisValue*/,
+                                 const jsi::Value * /*args*/,
+                                 size_t /*count*/) -> jsi::Value {
+    surfaceInfo->present();
+    return jsi::Value::undefined();
+  };
+  auto makeFn = [&]() {
+    return jsi::Function::createFromHostFunction(
+        runtime, jsi::PropNameID::forAscii(runtime, "WebGPUPresent"), 0,
+        presentCb);
+  };
+  // Try queueMicrotask first (Hermes JS thread). If the runtime disables
+  // microtasks (e.g. Worklets), fall back to setImmediate, then setTimeout —
+  // both have end-of-current-task semantics with no display latency.
+  try {
+    runtime.queueMicrotask(makeFn());
+    return JSIConverter<std::shared_ptr<GPUTexture>>::toJSI(
+        runtime, std::make_shared<GPUTexture>(texture, "", false));
+  } catch (...) {
+    // fall through
+  }
+  auto global = runtime.global();
+  if (global.hasProperty(runtime, "setImmediate")) {
+    auto setImmediate = global.getPropertyAsFunction(runtime, "setImmediate");
+    setImmediate.call(runtime, makeFn());
+  } else if (global.hasProperty(runtime, "setTimeout")) {
+    auto setTimeout = global.getPropertyAsFunction(runtime, "setTimeout");
+    setTimeout.call(runtime, makeFn(), jsi::Value(0));
+  }
 
   // Pass reportsMemoryPressure=false to avoid triggering spurious Hermes GC
   // cycles every frame since the canvas texture doesn't own the buffer.