From df89a16d265c3f02f403afefc0e60b5d227d94fb Mon Sep 17 00:00:00 2001
From: ocornut <omarcornut@gmail.com>
Date: Fri, 7 Aug 2020 15:34:25 +0200
Subject: [PATCH] Examples: Vulkan: Reworked buffer resize handling, fix for
 Linux/X11. (#3390, #2626)

---
 docs/CHANGELOG.txt                    |  1 +
 examples/example_glfw_vulkan/main.cpp | 18 ++++++++----------
 examples/example_sdl_vulkan/main.cpp  | 19 ++++++++-----------
 3 files changed, 17 insertions(+), 21 deletions(-)

diff --git a/docs/CHANGELOG.txt b/docs/CHANGELOG.txt
index 3f2a0474..a25f469c 100644
--- a/docs/CHANGELOG.txt
+++ b/docs/CHANGELOG.txt
@@ -51,6 +51,7 @@ Other Changes:
   (This is also necessary to support full multi/range-select/drag and drop operations.)
 - Metrics: Various tweaks, listing windows front-to-back, greying inactive items when possible.
 - Demo: Add simple InputText() callbacks demo (aside from the more elaborate ones in 'Examples->Console').
+- Examples: Vulkan: Reworked buffer resize handling, fix for Linux/X11. (#3390, #2626) [@RoryO]
 
 
 -----------------------------------------------------------------------
diff --git a/examples/example_glfw_vulkan/main.cpp b/examples/example_glfw_vulkan/main.cpp
index 58d0ab7f..8e75abbf 100644
--- a/examples/example_glfw_vulkan/main.cpp
+++ b/examples/example_glfw_vulkan/main.cpp
@@ -310,7 +310,7 @@ static void FrameRender(ImGui_ImplVulkanH_Window* wd, ImDrawData* draw_data)
     }
 }
 
-static void FramePresent(ImGui_ImplVulkanH_Window* wd)
+static void FramePresent(ImGui_ImplVulkanH_Window* wd, GLFWwindow* window)
 {
     VkSemaphore render_complete_semaphore = wd->FrameSemaphores[wd->SemaphoreIndex].RenderCompleteSemaphore;
     VkPresentInfoKHR info = {};
@@ -321,6 +321,12 @@ static void FramePresent(ImGui_ImplVulkanH_Window* wd)
     info.pSwapchains = &wd->Swapchain;
     info.pImageIndices = &wd->FrameIndex;
     VkResult err = vkQueuePresentKHR(g_Queue, &info);
+    if (err == VK_ERROR_OUT_OF_DATE_KHR)
+    {
+        glfwGetFramebufferSize(window, &g_SwapChainResizeWidth, &g_SwapChainResizeHeight);
+        g_SwapChainRebuild = true;
+        return;
+    }
     check_vk_result(err);
     wd->SemaphoreIndex = (wd->SemaphoreIndex + 1) % wd->ImageCount; // Now we can use the next set of semaphores
 }
@@ -330,13 +336,6 @@ static void glfw_error_callback(int error, const char* description)
     fprintf(stderr, "Glfw Error %d: %s\n", error, description);
 }
 
-static void glfw_resize_callback(GLFWwindow*, int w, int h)
-{
-    g_SwapChainRebuild = true;
-    g_SwapChainResizeWidth = w;
-    g_SwapChainResizeHeight = h;
-}
-
 int main(int, char**)
 {
     // Setup GLFW window
@@ -365,7 +364,6 @@ int main(int, char**)
     // Create Framebuffers
     int w, h;
     glfwGetFramebufferSize(window, &w, &h);
-    glfwSetFramebufferSizeCallback(window, glfw_resize_callback);
     ImGui_ImplVulkanH_Window* wd = &g_MainWindowData;
     SetupVulkanWindow(wd, surface, w, h);
 
@@ -515,7 +513,7 @@ int main(int, char**)
         {
             memcpy(&wd->ClearValue.color.float32[0], &clear_color, 4 * sizeof(float));
             FrameRender(wd, draw_data);
-            FramePresent(wd);
+            FramePresent(wd, window);
         }
     }
 
diff --git a/examples/example_sdl_vulkan/main.cpp b/examples/example_sdl_vulkan/main.cpp
index 6de7afab..c0a98088 100644
--- a/examples/example_sdl_vulkan/main.cpp
+++ b/examples/example_sdl_vulkan/main.cpp
@@ -302,7 +302,7 @@ static void FrameRender(ImGui_ImplVulkanH_Window* wd, ImDrawData* draw_data)
     }
 }
 
-static void FramePresent(ImGui_ImplVulkanH_Window* wd)
+static void FramePresent(ImGui_ImplVulkanH_Window* wd, SDL_Window* window)
 {
     VkSemaphore render_complete_semaphore = wd->FrameSemaphores[wd->SemaphoreIndex].RenderCompleteSemaphore;
     VkPresentInfoKHR info = {};
@@ -313,6 +313,12 @@ static void FramePresent(ImGui_ImplVulkanH_Window* wd)
     info.pSwapchains = &wd->Swapchain;
     info.pImageIndices = &wd->FrameIndex;
     VkResult err = vkQueuePresentKHR(g_Queue, &info);
+    if (err == VK_ERROR_OUT_OF_DATE_KHR)
+    {
+        SDL_GetWindowSize(window, &g_SwapChainResizeWidth, &g_SwapChainResizeHeight);
+        g_SwapChainRebuild = true;
+        return;
+    }
     check_vk_result(err);
     wd->SemaphoreIndex = (wd->SemaphoreIndex + 1) % wd->ImageCount; // Now we can use the next set of semaphores
 }
@@ -445,15 +451,6 @@ int main(int, char**)
             ImGui_ImplSDL2_ProcessEvent(&event);
             if (event.type == SDL_QUIT)
                 done = true;
-            if (event.type == SDL_WINDOWEVENT && event.window.event == SDL_WINDOWEVENT_RESIZED && event.window.windowID == SDL_GetWindowID(window))
-            {
-                // Note: your own application may rely on SDL_WINDOWEVENT_MINIMIZED/SDL_WINDOWEVENT_RESTORED to skip updating all-together.
-                // Here ImGui_ImplSDL2_NewFrame() will set io.DisplaySize to zero which will disable rendering but let application run.
-                // Please note that you can't Present into a minimized window.
-                g_SwapChainResizeWidth = (int)event.window.data1;
-                g_SwapChainResizeHeight = (int)event.window.data2;
-                g_SwapChainRebuild = true;
-            }
         }
 
         // Resize swap chain?
@@ -515,7 +512,7 @@ int main(int, char**)
         {
             memcpy(&wd->ClearValue.color.float32[0], &clear_color, 4 * sizeof(float));
             FrameRender(wd, draw_data);
-            FramePresent(wd);
+            FramePresent(wd, window);
         }
     }