From 769694ff9b2fede919e5b9325fc8a21893eafd5b Mon Sep 17 00:00:00 2001
From: Wojtek Figat <wojtek@figat.pl>
Date: Thu, 10 Sep 2026 13:34:26 +0200
Subject: [PATCH 1/2] Fix flickering on multi-windows on macOS regression from
 #4141

---
 .../GraphicsDevice/Vulkan/GPUSwapChainVulkan.cpp    | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/Source/Engine/GraphicsDevice/Vulkan/GPUSwapChainVulkan.cpp b/Source/Engine/GraphicsDevice/Vulkan/GPUSwapChainVulkan.cpp
index b259ed688..3bc38a765 100644
--- a/Source/Engine/GraphicsDevice/Vulkan/GPUSwapChainVulkan.cpp
+++ b/Source/Engine/GraphicsDevice/Vulkan/GPUSwapChainVulkan.cpp
@@ -135,6 +135,7 @@ GPUTextureView* GPUSwapChainVulkan::GetBackBufferView()
         PROFILE_CPU();
         auto context = _device->MainContext;
         auto cmdBufferManager = context->GetCmdBufferManager();
+
         // Keep commands recorded before acquire independent from the image-acquired semaphore wait below.
         if (cmdBufferManager->HasPendingActiveCmdBuffer())
             context->Flush();
@@ -152,7 +153,6 @@ GPUTextureView* GPUSwapChainVulkan::GetBackBufferView()
         acquiredBackBuffer.WaitForSubmit();
 
         const auto backBuffer = &_backBuffers[_acquiredImageIndex].Handle;
-
         auto cmdBuffer = cmdBufferManager->GetCmdBuffer();
 
         // Transition to render target (typical usage in most cases when calling backbuffer getter)
@@ -171,6 +171,17 @@ GPUTextureView* GPUSwapChainVulkan::GetBackBufferView()
 void GPUSwapChainVulkan::Begin(RenderTask* task)
 {
     GPUSwapChain::Begin(task);
+
+    // Wait for the backbuffer to be available
+    if (_currentImageIndex != -1)
+    {
+        auto& backBuffer = _backBuffers[_currentImageIndex];
+        if (backBuffer.SubmitCmdBuffer)
+        {
+            backBuffer.SubmitCmdBuffer->Wait();
+            backBuffer.SubmitCmdBuffer = nullptr;
+        }
+    }
 }
 
 bool GPUSwapChainVulkan::Resize(int32 width, int32 height)

From 796bdae4eaea6fb25edadde0e20da05e7ee8fb8b Mon Sep 17 00:00:00 2001
From: killerdevildog <quaylynrimer11@gmail.com>
Date: Sun, 13 Sep 2026 13:48:01 -0600
Subject: [PATCH 2/2] Fix ParseFloat rejecting a '+' sign in the exponent

---
 Source/Engine/Platform/Base/StringUtilsBase.cpp | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/Source/Engine/Platform/Base/StringUtilsBase.cpp b/Source/Engine/Platform/Base/StringUtilsBase.cpp
index 750758b33..fbf77a1f9 100644
--- a/Source/Engine/Platform/Base/StringUtilsBase.cpp
+++ b/Source/Engine/Platform/Base/StringUtilsBase.cpp
@@ -458,7 +458,16 @@ bool ParseFloat(const C* str, T* ret)
     if (*str == 'e' || *str == 'E')
     {
         str++;
-        T powerer = *str == '-' ? str++, (T)0.1 : (T)10;
+        T powerer = (T)10;
+        if (*str == '-')
+        {
+            powerer = (T)0.1;
+            str++;
+        }
+        else if (*str == '+')
+        {
+            str++;
+        }
         T power = 0;
         while (*str >= '0' && *str <= '9')
         {