imgui: Upgrade to docking branch, split init function to allow for im…

…gui configuration

middle title

CMakeLists.txt

@@ -5,7 +5,7 @@ set(CMAKE_CXX_STANDARD 17)
 
 set(GLFW_INC_DIRECTORY "/usr/include" CACHE FILEPATH "GLFW's include directory")
 
-include_directories(${GLFW_INC_DIRECTORY}/GLFW thirdparty/ ${PROJECT_SOURCE_DIR}/include)
+include_directories(${GLFW_INC_DIRECTORY}/GLFW thirdparty/ include/ include/blackcomb/imgui)
 
 add_library(blackcomb thirdparty/glad.c src/base/Window.cpp include/blackcomb/base/Window.h src/renderer/Shader.cpp include/blackcomb/renderer/Shader.h src/renderer/Mesh.cpp include/blackcomb/renderer/Mesh.h src/renderer/Texture.cpp include/blackcomb/renderer/Texture.h include/blackcomb/misc/BlackcombException.h src/misc/BlackcombException.cpp src/renderer/Model.cpp include/blackcomb/renderer/Model.h src/entities/BaseEntity.cpp include/blackcomb/entities/BaseEntity.h src/entities/RenderableEntity.cpp include/blackcomb/entities/RenderableEntity.h src/entities/Camera.cpp include/blackcomb/entities/Camera.h src/entities/FreeMoveCamera.cpp include/blackcomb/entities/FreeMoveCamera.h src/input/MouseWatcher.cpp include/blackcomb/input/MouseWatcher.h src/misc/BlackcombUtils.cpp include/blackcomb/misc/BlackcombUtils.h src/renderer/TextureAtlas.cpp include/blackcomb/renderer/TextureAtlas.h include/blackcomb/misc/Coords.h src/misc/Coords.cpp src/misc/RNG.cpp include/blackcomb/misc/RNG.h src/base/AppBase.cpp include/blackcomb/base/AppBase.h
         src/imgui/imgui.cpp src/imgui/imgui_draw.cpp src/imgui/imgui_widgets.cpp src/imgui/imgui_impl_glfw.cpp src/imgui/imgui_impl_opengl3.cpp src/imgui/imgui_demo.cpp

include/blackcomb/imgui/Wrapper.h

@@ -13,6 +13,8 @@ namespace blackcomb::imgui {
      */
     class Wrapper {
     public:
+        static void createContext();
+        static void simpleConfig();
         static void initialize(GLFWwindow* windowPtr, const char* glslVersion = nullptr, bool installCallbacks = true);
         static void beginFrame();
         static void render();

include/blackcomb/imgui/imgui_impl_glfw.h

@@ -7,6 +7,7 @@
 //  [X] Platform: Gamepad support. Enable with 'io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad'.
 //  [x] Platform: Mouse cursor shape and visibility. Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange'. FIXME: 3 cursors types are missing from GLFW.
 //  [X] Platform: Keyboard arrays indexed using GLFW_KEY_* codes, e.g. ImGui::IsKeyPressed(GLFW_KEY_SPACE).
+//  [X] Platform: Multi-viewport support (multiple windows). Enable with 'io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable'.
 
 // You can copy and use unmodified imgui_impl_* files in your project. See main.cpp for an example of using this.
 // If you are new to dear imgui, read examples/README.txt and read the documentation at the top of imgui.cpp.

include/blackcomb/imgui/imgui_impl_opengl3.h

@@ -4,6 +4,7 @@
 
 // Implemented features:
 //  [X] Renderer: User texture binding. Use 'GLuint' OpenGL texture identifier as void*/ImTextureID. Read the FAQ about ImTextureID in imgui.cpp.
+//  [X] Renderer: Multi-viewport support. Enable with 'io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable'.
 
 // You can copy and use unmodified imgui_impl_* files in your project. See main.cpp for an example of using this.
 // If you are new to dear imgui, read examples/README.txt and read the documentation at the top of imgui.cpp.

src/imgui/Wrapper.cpp

@@ -1,19 +1,44 @@
+#include <glfw3.h>
+#include <blackcomb/imgui/Wrapper.h>
+
 #include "blackcomb/imgui/Wrapper.h"
 
 namespace blackcomb::imgui {
     /**
-     * Initialize the imgui context and bindings.
-     * @param windowPtr The handle of the window to draw to
-     * @param glslVersion The GLSL version, defined as in a shader file (ie. "#version 150"), or nullptr for imgui's default.
-     * @param installCallbacks Whether or not imgui should register its callbacks with OpenGL.
+     * Creates the ImGui context. Call this before any other ImGui function!
      */
-    void Wrapper::initialize(GLFWwindow* windowPtr, const char* glslVersion, bool installCallbacks) {
-        // Setup context
+    void Wrapper::createContext() {
         IMGUI_CHECKVERSION();
         ImGui::CreateContext();
+    }
+
+    /**
+     * Sets up a simple, workable default configuration if you don't want to bother with it yourself.
+     * Enables viewports (you can remove UI panels from the window), docking (tabs/tiling), and the dark theme.
+     */
+    void Wrapper::simpleConfig() {
         ImGuiIO& io = ImGui::GetIO(); (void)io;
+        io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable; // Panels can be removed from the window
+        io.ConfigFlags |= ImGuiConfigFlags_DockingEnable; // You can tile panels or turn them into tabs
+
         // Use dark theme by default because this engine is RAD
         ImGui::StyleColorsDark();
+
+        // However, we should disable background opacity and corner rounding so we don't get visual discrepancies
+        ImGuiStyle& style = ImGui::GetStyle();
+        if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable) {
+            style.WindowRounding = 0.0f;
+            style.Colors[ImGuiCol_WindowBg].w = 1.0f;
+        }
+    }
+
+    /**
+     * Initialize the imgui context and bindings. Call after createContext and after configuring ImGui
+     * @param windowPtr The handle of the window to draw to
+     * @param glslVersion The GLSL version, defined as in a shader file (ie. "#version 150"), or nullptr for imgui's default.
+     * @param installCallbacks Whether or not imgui should register its callbacks with OpenGL.
+     */
+    void Wrapper::initialize(GLFWwindow* windowPtr, const char* glslVersion, bool installCallbacks) {
         // Setup platform bindings
         ImGui_ImplGlfw_InitForOpenGL(windowPtr, installCallbacks);
         ImGui_ImplOpenGL3_Init(glslVersion);
@@ -23,7 +48,7 @@ namespace blackcomb::imgui {
      * Should be called each frame you are drawing an imgui object, before rendering anything.
      * Informs imgui that a new frame has begun.
      */
-    void Wrapper::beginFrame(){
+    void Wrapper::beginFrame() {
         // Start the Dear ImGui frame
         ImGui_ImplOpenGL3_NewFrame();
         ImGui_ImplGlfw_NewFrame();
@@ -38,6 +63,15 @@ namespace blackcomb::imgui {
         // Rendering
         ImGui::Render();
         ImGui_ImplOpenGL3_RenderDrawData(ImGui::GetDrawData());
+
+        // Update other viewports
+        ImGuiIO& io = ImGui::GetIO(); (void)io;
+        if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable) {
+            GLFWwindow* contextBackup = glfwGetCurrentContext();
+            ImGui::UpdatePlatformWindows();
+            ImGui::RenderPlatformWindowsDefault();
+            glfwMakeContextCurrent(contextBackup);
+        }
     }
 
     /**