Handle closing windows

backends/imgui_impl_vulkan.cpp

@@ -1517,7 +1517,6 @@ static void ImGui_ImplVulkan_CreateWindow(ImGuiViewport* viewport)
 
 static void ImGui_ImplVulkan_DestroyWindow(ImGuiViewport* viewport)
 {
-    // The main viewport (owned by the application) will always have RendererUserData == NULL since we didn't create the data for it.
     if (ImGuiViewportDataVulkan* data = (ImGuiViewportDataVulkan*)viewport->RendererUserData)
     {
         ImGui_ImplVulkan_InitInfo* v = &g_VulkanInitInfo;
@@ -1557,6 +1556,7 @@ static void ImGui_ImplVulkan_RenderWindow(ImGuiViewport* viewport, void*)
             check_vk_result(err);
         }
         {
+        	//TODO fixme sometimes fails if multiple main windows and a separate window are open
             err = vkAcquireNextImageKHR(v->Device, wd->Swapchain, UINT64_MAX, fsd->ImageAcquiredSemaphore, VK_NULL_HANDLE, &wd->FrameIndex);
             check_vk_result(err);
             fd = &wd->Frames[wd->FrameIndex];

imgui.cpp

@@ -937,7 +937,6 @@ static void             EndFrameDrawDimmedBackgrounds();
 
 // Viewports
 const ImGuiID           IMGUI_VIEWPORT_DEFAULT_ID = 0x11111111; // Using an arbitrary constant instead of e.g. ImHashStr("ViewportDefault", 0); so it's easier to spot in the debugger. The exact value doesn't matter.
-ImGuiViewportP*  AddUpdateViewport(ImGuiWindow* window, ImGuiID id, const ImVec2& platform_pos, const ImVec2& size, ImGuiViewportFlags flags);
 static void             UpdateViewportsNewFrame();
 static void             UpdateViewportsEndFrame();
 static void             UpdateSelectWindowViewport(ImGuiWindow* window);
@@ -11546,7 +11545,7 @@ static void ImGui::UpdateViewportsNewFrame()
         viewport->Idx = n;
 
         // Erase unused viewports
-        if (n > 0 && viewport->LastFrameActive < g.FrameCount - 2)
+        if ((viewport->Flags & ImGuiViewportFlags_OwnedByApp) == 0 && viewport->LastFrameActive < g.FrameCount - 2)
         {
             // Clear references to this viewport in windows (window->ViewportId becomes the master data)
             for (int window_n = 0; window_n < g.Windows.Size; window_n++)
@@ -11701,14 +11700,14 @@ static void ImGui::UpdateViewportsEndFrame()
         viewport->LastPos = viewport->Pos;
 
         if (viewport->LastFrameActive < g.FrameCount || viewport->Size.x <= 0.0f || viewport->Size.y <= 0.0f) {
-        	if ((viewport->Flags & (ImGuiViewportFlags_OwnedByApp | ImGuiViewportFlags_CanHostOtherWindows)) == 0)
+        	if ((viewport->Flags & ImGuiViewportFlags_OwnedByApp) == 0)
         		continue;
         }
 
         if (viewport->Window && !IsWindowActiveAndVisible(viewport->Window))
             continue;
 
-        if ((viewport->Flags & (ImGuiViewportFlags_OwnedByApp | ImGuiViewportFlags_CanHostOtherWindows)) == 0) {
+        if ((viewport->Flags & ImGuiViewportFlags_OwnedByApp) == 0) {
         	IM_ASSERT(viewport->Window != NULL);
         }
 
@@ -11780,6 +11779,52 @@ ImGuiViewportP* ImGui::AddUpdateViewport(ImGuiWindow* window, ImGuiID id, const
     return viewport;
 }
 
+void ImGui::EraseViewport(ImGuiViewportP* viewport) {
+	IM_ASSERT(viewport != NULL);
+	ImGuiContext& g = *GImGui;
+	IM_ASSERT(g.PlatformIO.Viewports.Size <= g.Viewports.Size);
+
+	// Clear references to this viewport in windows (window->ViewportId becomes the master data)
+	for (int window_n = 0; window_n < g.Windows.Size; window_n++)
+			if (g.Windows[window_n]->Viewport == viewport)
+			{
+					g.Windows[window_n]->Viewport = (ImGuiViewportP*) GetMainViewport();
+//					g.Windows[window_n]->ViewportOwned = false;
+			}
+
+	if (viewport == g.MouseLastHoveredViewport)
+			g.MouseLastHoveredViewport = NULL;
+
+	int n=-1;
+	for (int i = 0; i < g.Viewports.Size; i++) {
+		if (g.Viewports[i] == viewport) {
+			n = i;
+			break;
+		}
+	}
+
+	IM_ASSERT(n >= 0);
+
+	g.Viewports.erase(g.Viewports.Data + n);
+
+	// Destroy
+	IMGUI_DEBUG_LOG_VIEWPORT("Delete Viewport %08X (%s)\n", viewport->ID, viewport->Window ? viewport->Window->Name : "n/a");
+	DestroyPlatformWindow(viewport);
+
+	n=-1;
+	for (int i = 0; i < g.PlatformIO.Viewports.Size; i++) {
+		if (g.PlatformIO.Viewports[i] == viewport) {
+			n = i;
+			break;
+		}
+	}
+
+	IM_ASSERT(n >= 0);
+	g.PlatformIO.Viewports.erase(g.PlatformIO.Viewports.Data + n);
+
+	IM_DELETE(viewport);
+}
+
 // FIXME-VIEWPORT: This is all super messy and ought to be clarified or rewritten.
 static void ImGui::UpdateSelectWindowViewport(ImGuiWindow* window)
 {

imgui.h

@@ -833,7 +833,7 @@ namespace ImGui
     // - Currently represents the Platform Window created by the application which is hosting our Dear ImGui windows.
     // - In 'docking' branch with multi-viewport enabled, we extend this concept to have multiple active viewports.
     // - In the future we will extend this concept further to also represent Platform Monitor and support a "no main platform window" operation mode.
-    IMGUI_API ImGuiViewport* GetMainViewport();                                                 // return primary/default viewport. This can never be NULL.
+    IMGUI_API ImGuiViewport*  GetMainViewport();     // return primary/default viewport. This can never be NULL.
 
     // Miscellaneous Utilities
     IMGUI_API bool          IsRectVisible(const ImVec2& size);                                  // test if rectangle (of given size, starting from cursor position) is visible / not clipped.

imgui_internal.h

@@ -2473,6 +2473,8 @@ namespace ImGui
     IMGUI_API void          CallContextHooks(ImGuiContext* context, ImGuiContextHookType type);
 
     // Viewports
+    IMGUI_API ImGuiViewportP*       AddUpdateViewport(ImGuiWindow* window, ImGuiID id, const ImVec2& platform_pos, const ImVec2& size, ImGuiViewportFlags flags);
+    IMGUI_API void                  EraseViewport(ImGuiViewportP*);
     IMGUI_API void                  TranslateWindowsInViewport(ImGuiViewportP* viewport, const ImVec2& old_pos, const ImVec2& new_pos);
     IMGUI_API void                  ScaleWindowsInViewport(ImGuiViewportP* viewport, float scale);
     IMGUI_API void                  DestroyPlatformWindow(ImGuiViewportP* viewport);