Prevent rendering during close and validate surface

Add m_isClosing flag and closeEvent to stop rendering, stop the render
timer and wait for device idle. Guard swapchain creation and recreation
to abort when closing. Check Vulkan return values and detect invalid
surface capabilities to avoid crashes during window teardown.

src/vulkanwidget.cpp

@@ -5,6 +5,7 @@
 #include <QHideEvent>
 #include <QResizeEvent>
 #include <QPaintEvent>
+#include <QCloseEvent>
 #include <QWindow>
 #include <QApplication>
 #include <algorithm>
@@ -52,6 +53,7 @@ VulkanWidget::VulkanWidget(QWidget *parent)
     , m_lastLockFrameCount(0)
     , m_lockPaintFrameCount(0)
     , m_lockCount(0)
+    , m_isClosing(false)
 {
     // Set widget attributes for native window
     setAttribute(Qt::WA_NativeWindow);
@@ -483,9 +485,20 @@ bool VulkanWidget::createSwapchain()
     qDebug() << "Widget size:" << width() << "x" << height();
     qDebug() << "Device pixel ratio:" << devicePixelRatioF();
 
+    // Don't create swapchain if closing
+    if (m_isClosing) {
+        qDebug() << "Aborting swapchain creation - widget is closing";
+        return false;
+    }
+
     // Query surface capabilities
     VkSurfaceCapabilitiesKHR capabilities;
-    vkGetPhysicalDeviceSurfaceCapabilitiesKHR(m_physicalDevice, m_surface, &capabilities);
+    VkResult result = vkGetPhysicalDeviceSurfaceCapabilitiesKHR(m_physicalDevice, m_surface, &capabilities);
+    
+    if (result != VK_SUCCESS) {
+        qDebug() << "Failed to get surface capabilities, error code:" << result;
+        return false;
+    }
 
     qDebug() << "Surface capabilities - current extent:"
              << capabilities.currentExtent.width << "x" << capabilities.currentExtent.height;
@@ -494,6 +507,16 @@ bool VulkanWidget::createSwapchain()
     qDebug() << "Surface capabilities - max extent:"
              << capabilities.maxImageExtent.width << "x" << capabilities.maxImageExtent.height;
     
+    // Validate surface capabilities - detect invalid/corrupted values
+    // This can happen when the window is being destroyed
+    if (capabilities.currentExtent.width > 16384 || capabilities.currentExtent.height > 16384 ||
+        capabilities.minImageExtent.width > 16384 || capabilities.minImageExtent.height > 16384 ||
+        capabilities.maxImageExtent.width > 1000000 || capabilities.maxImageExtent.height > 1000000) {
+        qDebug() << "ERROR: Invalid surface capabilities detected - surface may be destroyed";
+        qDebug() << "This usually happens when the window is being closed";
+        return false;
+    }
+
     // Query surface formats
     uint32_t formatCount;
     vkGetPhysicalDeviceSurfaceFormatsKHR(m_physicalDevice, m_surface, &formatCount, nullptr);
@@ -576,9 +599,9 @@ bool VulkanWidget::createSwapchain()
     createInfo.clipped = VK_TRUE;
     createInfo.oldSwapchain = VK_NULL_HANDLE;
 
-    VkResult result = vkCreateSwapchainKHR(m_device, &createInfo, nullptr, &m_swapchain);
+    VkResult swapchainResult = vkCreateSwapchainKHR(m_device, &createInfo, nullptr, &m_swapchain);
-    if (result != VK_SUCCESS) {
+    if (swapchainResult != VK_SUCCESS) {
-        qDebug() << "Failed to create swapchain, error code:" << result;
+        qDebug() << "Failed to create swapchain, error code:" << swapchainResult;
         return false;
     }
 
@@ -607,9 +630,9 @@ bool VulkanWidget::createSwapchain()
         viewInfo.subresourceRange.layerCount = 1;
 
         VkImageView imageView;
-        result = vkCreateImageView(m_device, &viewInfo, nullptr, &imageView);
+        VkResult viewResult = vkCreateImageView(m_device, &viewInfo, nullptr, &imageView);
-        if (result != VK_SUCCESS) {
+        if (viewResult != VK_SUCCESS) {
-            qDebug() << "Failed to create image view" << i << ", error code:" << result;
+            qDebug() << "Failed to create image view" << i << ", error code:" << viewResult;
             return false;
         }
         m_swapchainImageViews[i] = reinterpret_cast<void*>(imageView);
@@ -686,6 +709,12 @@ bool VulkanWidget::recreateSwapchain()
 {
     qDebug() << "Recreating swapchain...";
     
+    // Don't recreate if closing
+    if (m_isClosing) {
+        qDebug() << "Aborting swapchain recreation - widget is closing";
+        return false;
+    }
+
     // Wait for device to be idle
     vkDeviceWaitIdle(m_device);
 
@@ -710,7 +739,8 @@ bool VulkanWidget::recreateSwapchain()
 
 void VulkanWidget::renderFrame()
 {
-    if (!m_initialized) {
+    // Don't render if closing or not initialized
+    if (!m_initialized || m_isClosing) {
         return;
     }
 
@@ -993,6 +1023,29 @@ void VulkanWidget::hideEvent(QHideEvent *event)
     setRenderingEnabled(false);
 }
 
+void VulkanWidget::closeEvent(QCloseEvent *event)
+{
+    qDebug() << "VulkanWidget closeEvent - stopping rendering and cleaning up";
+    
+    // Set closing flag to prevent any further rendering attempts
+    m_isClosing = true;
+    
+    // Stop the render timer immediately
+    if (m_renderTimer) {
+        m_renderTimer->stop();
+        qDebug() << "Render timer stopped on close";
+    }
+    
+    // Wait for device to be idle before accepting close event
+    if (m_device != VK_NULL_HANDLE) {
+        vkDeviceWaitIdle(m_device);
+        qDebug() << "Vulkan device idle on close";
+    }
+    
+    // Accept the close event
+    QWidget::closeEvent(event);
+}
+
 void VulkanWidget::resizeEvent(QResizeEvent *event)
 {
     QWidget::resizeEvent(event);

src/vulkanwidget.h

@@ -62,6 +62,11 @@ protected:
      */
     void hideEvent(QHideEvent *event) override;
 
+    /**
+     * @brief Qt事件：窗口关闭时
+     */
+    void closeEvent(QCloseEvent *event) override;
+
     /**
      * @brief Qt事件：组件大小改变时
      */
@@ -208,6 +213,7 @@ private:
     bool m_renderingEnabled;
     bool m_needsResize;
     bool m_needsLockedFrameUpdate; // 是否需要渲染锁屏帧（锁屏时只渲染一帧）
+    bool m_isClosing; // 标记窗口正在关闭，防止在销毁过程中继续渲染
     int m_frameCount;
     uint32_t m_queueFamilyIndex;
     uint32_t m_currentFrame;