From fd19fc1c6810c1e79d930d6564e13bc62c858c73 Mon Sep 17 00:00:00 2001
From: Nick Fisher <nick.fisher@avinium.com>
Date: Fri, 21 Jun 2024 11:18:05 +0800
Subject: [PATCH] fix: use preserveDrawingBuffer=true on web

using createImageFromImageBitmap to import the canvas directly into a Flutter app results in flickering unless this is set to true (as the drawing buffer is otherwise cleared after each render, which may not line up with Flutter's ticker
---
 thermion_dart/native/web/src/cpp/ThermionDartWebApi.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/thermion_dart/native/web/src/cpp/ThermionDartWebApi.cpp b/thermion_dart/native/web/src/cpp/ThermionDartWebApi.cpp
index a55270ca..0c441841 100644
--- a/thermion_dart/native/web/src/cpp/ThermionDartWebApi.cpp
+++ b/thermion_dart/native/web/src/cpp/ThermionDartWebApi.cpp
@@ -125,7 +125,7 @@ extern "C"
     attr.stencil = EM_FALSE;
     attr.antialias = EM_FALSE;
     attr.explicitSwapControl = EM_FALSE;
-    attr.preserveDrawingBuffer = EM_FALSE;
+    attr.preserveDrawingBuffer = EM_TRUE;
     attr.proxyContextToMainThread = EMSCRIPTEN_WEBGL_CONTEXT_PROXY_DISALLOW;
     attr.enableExtensionsByDefault = EM_TRUE;
     attr.renderViaOffscreenBackBuffer = EM_FALSE;