xo-imgui: imgui_ex4 working on native ubuntu

requires etc/hostubuntu shim

xo-imgui/example/ex4/imgui_ex4.cpp

@@ -1,9 +1,6 @@
 /* imgui_ex4.cpp */
 
 #include "xo/imgui/VulkanApp.hpp"
-#ifdef TEMPORARILY_REMOVE
-#include "xo/imgui/ImRect.hpp"
-#endif
 #include "AppState.hpp"
 #include "DrawState.hpp"
 #include <backends/imgui_impl_sdl2.h>
@@ -87,9 +84,7 @@ namespace {
             {
                 scope log(XO_DEBUG(false));
 
-#ifdef TEMPORARILY_REMOVE
                 app_duty_cycle_top(p_app_state, p_draw_state);
-#endif
 
                 log && log(xtag("imgui_cx", (void*)ImGui::GetCurrentContext()));
 
@@ -98,7 +93,6 @@ namespace {
                 ImGui_ImplSDL2_NewFrame();
                 ImGui::NewFrame();
 
-#ifdef TEMPORARILY_REMOVE
                 log && log("after NewFrame", xtag("imgui_cx", (void*)ImGui::GetCurrentContext()));
 
                 ImGuiIO & io = ImGui::GetIO(); (void)io;
@@ -113,12 +107,10 @@ namespace {
                              | ImGuiWindowFlags_NoNavFocus | ImGuiWindowFlags_NoDecoration);
                 ImGui::End();
 # endif
-#endif
 
                 // 1. create a simple ImGui window
                 ImGui::Begin("Hello, Vulkan + SDL2!");
                 ImGui::Text("This is a minimal ImGui + Vulkan + SDL2 example!");
-#ifdef TEMPORARILY_REMOVE
                 ImGui::Text("appl average %.3f ms/frame (%.1f fps)",
                             1000.0f / io.Framerate, io.Framerate);
 
@@ -212,15 +204,12 @@ namespace {
                         p_app_state->copy_detail_tenured_dest_size_       = 0;
                     }
                 }
-#endif
 
                 ImGui::End();
 
-#ifdef TEMPORARILY_REMOVE
                 // 2. big demo window
                 if (p_draw_state->show_demo_window_)
                     ImGui::ShowDemoWindow(&p_draw_state->show_demo_window_);
-#endif
 
                 // Rendering
                 ImGui::Render();
@@ -296,13 +285,10 @@ int main() {
         = make_imgui_draw_frame(&app_state, &draw_state, &f, &counter);
     VulkanApp vk_app(draw_fn);
 
-    /* establishes imgui context */
     vk_app.setup(app_imgui_load_fonts);
 
-#ifdef NOT_YET
     app_state.gc_->add_gc_copy_callback
         (draw_state.make_gc_copy_animation(&app_state));
-#endif
 
     try {
         vk_app.main_loop();

xo-imgui/example/ex4a/VulkanApp.cpp

@@ -41,10 +41,7 @@ MinimalImGuiVulkan::init_vulkan()
     this->create_surface();
     this->pick_physical_device();
     this->create_logical_device();
-    this->create_swapchain();
-    this->create_image_views();
-    this->create_render_pass();   // must come before createFrameBuffers
-    this->create_framebuffers();
+    this->create_xswapchain(true /*create_render_pass_flag*/);
     this->create_command_pool();
     this->create_command_buffers();
     this->create_sync_objects();
@@ -503,7 +500,7 @@ MinimalImGuiVulkan::draw_frame()
     case VK_SUBOPTIMAL_KHR:
         break;
     case VK_ERROR_OUT_OF_DATE_KHR:
-        recreate_swapchain();
+        this->recreate_xswapchain();
         // deliberate earlyexit
         return;
     default:
@@ -559,7 +556,7 @@ MinimalImGuiVulkan::draw_frame()
     case VK_ERROR_OUT_OF_DATE_KHR:
     case VK_SUBOPTIMAL_KHR:
         framebuffer_resized_flag_ = false;
-        this->recreate_swapchain();
+        this->recreate_xswapchain();
         break;
     default:
         throw std::runtime_error("failed to present swapchain image!");
@@ -624,7 +621,25 @@ MinimalImGuiVulkan::record_command_buffer(VkCommandBuffer cmdbuf, uint32_t image
 }
 
 void
-MinimalImGuiVulkan::recreate_swapchain()
+MinimalImGuiVulkan::create_xswapchain(bool create_render_pass_flag)
+{
+    this->create_swapchain();
+    this->create_image_views();
+    if(create_render_pass_flag)
+        this->create_render_pass();
+    this->create_framebuffers();
+}
+
+void
+MinimalImGuiVulkan::cleanup_xswapchain()
+{
+    this->cleanup_framebuffers();
+    this->cleanup_image_views();
+    this->cleanup_swapchain();
+}
+
+void
+MinimalImGuiVulkan::recreate_xswapchain()
 {
     // handle window minimization: wait until window has valid size
     this->wait_not_minimized();
@@ -632,15 +647,11 @@ MinimalImGuiVulkan::recreate_swapchain()
     // wait until device idle before cleaning up resources
     vkDeviceWaitIdle(device_);
 
-    // cleanup old swapchain
-    this->cleanup_framebuffers();
-    this->cleanup_image_views();
-    this->cleanup_swapchain();
+    // cleanup old xswapchain
+    this->cleanup_xswapchain();
 
     // create new swapchain
-    this->create_swapchain();
-    this->create_image_views();
-    this->create_framebuffers();
+    this->create_xswapchain(false);
 }
 
 void
@@ -694,9 +705,7 @@ MinimalImGuiVulkan::cleanup()
 
     vkDestroyCommandPool(device_, command_pool_, nullptr);
 
-    this->cleanup_framebuffers();
-    this->cleanup_image_views();
-    this->cleanup_swapchain();
+    this->cleanup_xswapchain();
 
     vkDestroyRenderPass(device_, render_pass_, nullptr);
     vkDestroyDescriptorPool(device_, descriptor_pool_, nullptr);

xo-imgui/example/ex4a/VulkanApp.hpp

@@ -47,6 +47,12 @@ private:
      */
     void create_logical_device();
 
+    /* populates @ref swapchain_, @ref swapchain_images_,
+     * @ref swapchain_image_views_, @ref framebuffers_.
+     * Also $ref render_pass_ iff @p create_render_pass_flag
+     */
+    void create_xswapchain(bool create_render_pass_flag);
+
     /*
      * populates @ref swapchain_, @ref swapchain_images_
      */
@@ -123,11 +129,14 @@ private:
     /* Teardown + create swapchain (swapchain + framebuffers + image views).
      * Need this after window size changes
      */
-    void recreate_swapchain();
+    void recreate_xswapchain();
 
     /* wait until non-minimized window */
     void wait_not_minimized();
 
+    /* orderly disposal of swapchin + image_views + framebuffers */
+    void cleanup_xswapchain();
+
     /* orderly disposal of @ref framebuffers_ */
     void cleanup_framebuffers();