From a2ee85f47799b625039602f9ef5948d24b46cc90 Mon Sep 17 00:00:00 2001
From: Haroon Qureshi <haroonq@google.com>
Date: Fri, 24 Apr 2026 06:41:48 -0700
Subject: [PATCH] Fix wasm flickering.

Always execute the engine in non-threading (wasm) builds.
And stop rendering if any beginFrame call returns false.

PiperOrigin-RevId: 905000139
Change-Id: I0a6f06a07a8fc0ab0251a67be13a9d170d4a905d
---
 .../filament/filament/filament_context.cc           | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/src/experimental/filament/filament/filament_context.cc b/src/experimental/filament/filament/filament_context.cc
index 8c159ce2..e367b44f 100644
--- a/src/experimental/filament/filament/filament_context.cc
+++ b/src/experimental/filament/filament/filament_context.cc
@@ -118,6 +118,9 @@ FilamentContext::FrameHandle FilamentContext::Render(
       if (!render_began) {
         render_began = renderer_->beginFrame(window_swap_chain_);
       }
+      if (!render_began) {
+        break;
+      }
       if (render_began) {
         SceneView::RenderRequest scene_view_request;
         scene_view_request.draw_mode = request.draw_mode;
@@ -139,6 +142,9 @@ FilamentContext::FrameHandle FilamentContext::Render(
       if (!render_began) {
         render_began = renderer_->beginFrame(offscreen_swap_chain_);
       }
+      if (!render_began) {
+        break;
+      }
       if (render_began) {
         SceneView::RenderRequest scene_view_request;
         scene_view_request.draw_mode = request.draw_mode;
@@ -154,10 +160,9 @@ FilamentContext::FrameHandle FilamentContext::Render(
 
   if (render_began) {
     renderer_->endFrame();
-    render_began = false;
-    if constexpr (!UTILS_HAS_THREADING) {
-      engine_->execute();
-    }
+  }
+  if constexpr (!UTILS_HAS_THREADING) {
+    engine_->execute();
   }
 
   if (!read_requests.empty()) {