Rewrote UI System as an extension under namespace nbl::ext::imgui. I have a linking issue that fixed it with a trick I saw in Blur. I'm going to ask for real solution and check what I have done wrong.

Author: MohammadFakhreddin

3rdparty/CMakeLists.txt

@@ -266,22 +266,23 @@ add_library(spirv_cross OBJECT
 )
 target_compile_definitions(spirv_cross PUBLIC SPIRV_CROSS_EXCEPTIONS_TO_ASSERTIONS)
 
-
-add_library(imgui
-	"imgui/imconfig.h"
-	"imgui/imgui_demo.cpp"
-	"imgui/imgui_draw.cpp"
-	"imgui/imgui_internal.h"
-	"imgui/imgui_tables.cpp"
-	"imgui/imgui_widgets.cpp"
-	"imgui/imgui.cpp"
-	"imgui/imgui.h"
-	"imgui/imgui_stdlib.cpp"
-	"imgui/imgui_stdlib.h"
-	"imgui/imstb_rectpack.h"
-	"imgui/imstb_textedit.h"
-	"imgui/imstb_truetype.h"
-)
+if(NBL_BUILD_IMGUI)
+	add_library(imgui
+		"imgui/imconfig.h"
+		"imgui/imgui_demo.cpp"
+		"imgui/imgui_draw.cpp"
+		"imgui/imgui_internal.h"
+		"imgui/imgui_tables.cpp"
+		"imgui/imgui_widgets.cpp"
+		"imgui/imgui.cpp"
+		"imgui/imgui.h"
+		"imgui/imgui_stdlib.cpp"
+		"imgui/imgui_stdlib.h"
+		"imgui/imstb_rectpack.h"
+		"imgui/imstb_textedit.h"
+		"imgui/imstb_truetype.h"
+	)
+endif()
 
 add_library(aesGladman OBJECT
 	aesGladman/aes_ni.c
@@ -368,7 +369,6 @@ set(NBL_3RDPARTY_TARGETS
 				SPIRV-Tools-static # SPIRV-Tools-shared in case of SHARED lib
 				SPIRV-Tools-opt
 				egl 
-				imgui
 )
 if (_NBL_COMPILE_WITH_OPEN_EXR_)
 	list(APPEND NBL_3RDPARTY_TARGETS
@@ -391,6 +391,9 @@ endif()
 if (NBL_BUILD_MITSUBA_LOADER)
 	list(APPEND NBL_3RDPARTY_TARGETS expat)
 endif()
+if (NBL_BUILD_IMGUI)
+	list(APPEND NBL_3RDPARTY_TARGETS imgui)
+endif()
 if(ENABLE_HLSL)
 	list(APPEND NBL_3RDPARTY_TARGETS HLSL)
 endif()

CMakeLists.txt

@@ -253,7 +253,9 @@ option(NBL_BUILD_EXAMPLES "Enable building examples" ON)
 
 option(NBL_BUILD_TOOLS "Enable building tools (just convert2BAW as for now)" ON)
 
-option(NBL_BUILD_MITSUBA_LOADER "Enable nbl::ext::MitsubaLoader?" ON)
+option(NBL_BUILD_MITSUBA_LOADER "Enable nbl::ext::MitsubaLoader?" OFF)
+
+option(NBL_BUILD_IMGUI "Enable nbl::ext::ImGui?" ON)
 
 if (NBL_COMPILE_WITH_CUDA)
 	find_package(OPTIX)

examples_tests/61.UI/CMakeLists.txt

@@ -1,12 +1,16 @@
+if(NBL_BUILD_IMGUI)
+
 include(common RESULT_VARIABLE RES)
 if(NOT RES)
 	message(FATAL_ERROR "common.cmake not found. Should be in {repo_root}/cmake directory")
 endif()
 
-set(EXTRA_SOURCES "")
-list(APPEND EXTRA_SOURCES 
-	"UI_System.cpp" 
-	"UI_System.hpp"
+list(APPEND libs 
+	"imgui"
+	"${NBL_EXT_IMGUI_LIB}"
 )
 
-nbl_create_executable_project("${EXTRA_SOURCES}" "" "" "imgui")
+# I'll ask about why it is not working about me adding imGui.cpp manually
+nbl_create_executable_project("../../src/nbl/ext/ImGui/ImGui.cpp" "" "" "${libs}")
+
+endif()

examples_tests/61.UI/UI_System.hpp

@@ -5,10 +5,9 @@
 #define _NBL_STATIC_LIB_
 #include <nabla.h>
 
-
 #include "../common/CommonAPI.h"
-
-#include "UI_System.hpp"
+#include "nbl/ext/ImGui/ImGui.h"
+#include "nbl/ui/ICursorControl.h"
 
 using namespace nbl;
 using namespace asset;
@@ -114,26 +113,24 @@ class UIApp : public ApplicationBase
 
 			nbl::video::IGPUObjectFromAssetConverter cpu2gpu;
 
-			// TOOD: Pass pipeline cache in future
-			UI::Init(
+			ui = core::make_smart_refctd_ptr<nbl::ext::imgui::UI>(
 				logicalDevice, 
 				FRAMES_IN_FLIGHT,
 				renderpass, 
 				nullptr, 
 				cpu2gpuParams,
-				inputSystem,
 				window
 			);
 
-			UI::Register([]()->void{
-				UI::BeginWindow("Test window");
-				UI::SetNextItemWidth(100);
-				UI::Text("Hi");
-				UI::SetNextItemWidth(100);
-				UI::Button("Button", []()->void {
+			ui->Register([this]()->void{
+				ui->BeginWindow("Test window");
+				ui->SetNextItemWidth(100);
+				ui->Text("Hi");
+				ui->SetNextItemWidth(100);
+				ui->Button("Button", []()->void {
 					printf("Button pressed!\n");
 				});
-				UI::EndWindow();
+				ui->EndWindow();
 			});
 
 			logicalDevice->createCommandBuffers(commandPools[CommonAPI::InitOutput::EQT_GRAPHICS].get(),video::IGPUCommandBuffer::EL_PRIMARY,FRAMES_IN_FLIGHT,commandBuffers);
@@ -149,7 +146,6 @@ class UIApp : public ApplicationBase
 		void onAppTerminated_impl() override
 		{
 			logicalDevice->waitIdle();
-			UI::Shutdown();
 		}
 
 		void workLoopBody() override
@@ -202,9 +198,10 @@ class UIApp : public ApplicationBase
 
 			commandBuffer->beginRenderPass(&beginInfo, nbl::asset::ESC_INLINE);
 
+			// TODO: Use real deltaTime instead
 			float deltaTimeInSec = 0.1f;
-			// TODO: Use deltaTime instead
-			UI::Render(*commandBuffer, resourceIx);
+			
+			ui->Render(*commandBuffer, resourceIx);
 
 			commandBuffer->endRenderPass();
 			commandBuffer->end();
@@ -228,7 +225,36 @@ class UIApp : public ApplicationBase
 				acquiredNextFBO
 			);
 
-			UI::Update(deltaTimeInSec);
+			CommonAPI::InputSystem::ChannelReader<IMouseEventChannel> mouse;
+
+			inputSystem->getDefaultMouse(&mouse);
+
+			static std::chrono::microseconds previousEventTimestamp {};
+
+			std::vector<SMouseEvent> validEvents {};
+
+			mouse.consumeEvents([&validEvents](const IMouseEventChannel::range_t& events) -> void {
+				for (auto event : events)
+				{
+					if (event.timeStamp < previousEventTimestamp)
+					{
+						continue;
+					}
+					previousEventTimestamp = event.timeStamp;
+
+					validEvents.push_back(event);
+				}
+			});
+
+			auto const mousePosition = window->getCursorControl()->getPosition();
+
+			ui->Update(
+				deltaTimeInSec, 
+				static_cast<float>(mousePosition.x), 
+				static_cast<float>(mousePosition.y),
+				validEvents.size(),
+				validEvents.data()
+			);
 		}
 
 		bool keepRunning() override
@@ -260,7 +286,9 @@ class UIApp : public ApplicationBase
 		core::smart_refctd_ptr<video::IGPUFence> frameComplete[FRAMES_IN_FLIGHT] = { nullptr };
 		core::smart_refctd_ptr<video::IGPUSemaphore> imageAcquire[FRAMES_IN_FLIGHT] = { nullptr };
 		core::smart_refctd_ptr<video::IGPUSemaphore> renderFinished[FRAMES_IN_FLIGHT] = { nullptr };
-		
+
+		nbl::core::smart_refctd_ptr<nbl::ext::imgui::UI> ui {};
+
 		_NBL_STATIC_INLINE_CONSTEXPR uint64_t MAX_TIMEOUT = 99999999999999ull;
 		uint32_t acquiredNextFBO = {};
 		int32_t resourceIx = -1;

examples_tests/61.UI/main.cpp

@@ -1,4 +1,5 @@
-#pragma once
+#ifndef COMMON_API_H
+#define COMMON_API_H
 
 #define _NBL_STATIC_LIB_
 #include <nabla.h>
@@ -1854,3 +1855,4 @@ CommonAPI::main<app_class>(argc, argv);\
 #endif
 //***** Application framework macros ******
 
+#endif

examples_tests/common/CommonAPI.h

@@ -98,12 +98,6 @@ class smart_refctd_ptr
 		inline I_REFERENCE_COUNTED& operator[](size_t idx) { return ptr[idx]; }
 		inline const I_REFERENCE_COUNTED& operator[](size_t idx) const { return ptr[idx]; }
 
-		[[nodiscard]]
-		bool isValid() const noexcept
-		{
-			return ptr != nullptr;
-		}
-
 		inline explicit operator bool() const { return ptr; }
 		inline bool operator!() const { return !ptr; }