WIP : Add imgui based client to test that ui library

3rdparty/imgui

@@ -0,0 +1 @@
+Subproject commit c077dd4872f435dd959feb024e5a9adb2c7df20c

CMakeLists.txt

@@ -8,10 +8,13 @@ find_package(PkgConfig REQUIRED)
 
 # OpenGL
 find_package(OpenGL REQUIRED)
-#find_package(GLEW REQUIRED)
 find_package(GLUT REQUIRED)
 pkg_search_module(GLFW REQUIRED glfw3)
 
+# I can't get glew to initial windows. Always fails
+# with error 4 (Unknown) on Debian sid. - Kienan 2019.08.03
+#find_package(GLEW REQUIRED)
+
 # Glad
 set(GLAD_API "gl=3.3" CACHE STRING " " FORCE)
 add_subdirectory("${PROJECT_SOURCE_DIR}/3rdparty/glad")
@@ -19,13 +22,43 @@ add_subdirectory("${PROJECT_SOURCE_DIR}/3rdparty/glad")
 # Nuklear
 set(NUKLEAR_INCLUDE_DIR "${PROJECT_SOURCE_DIR}/3rdparty/nuklear")
 
-#Client
+# Imgui
+add_definitions(-DIMGUI_IMPL_LOADER_GLAD)
+set(imgui_dir "${PROJECT_SOURCE_DIR}/3rdparty/imgui")
+add_library(imgui STATIC
+  ${imgui_dir}/imgui.h
+  ${imgui_dir}/imstb_rectpack.h ${imgui_dir}/imstb_textedit.h ${imgui_dir}/imstb_truetype.h ${imgui_dir}/imgui_internal.h
+  ${imgui_dir}/imgui.cpp ${imgui_dir}/imgui_draw.cpp ${imgui_dir}/imgui_widgets.cpp)
+target_compile_definitions(imgui PUBLIC -DIMGUI_IMPL_OPENGL_LOADER_GLAD)
+target_include_directories(imgui PUBLIC ${imgui_dir})
+
+# Imgui glfw-gl3
+set(igo_dir "${imgui_dir}/examples")
+add_library(imgui-glfw-gl3 STATIC
+  ${igo_dir}/imgui_impl_glfw.h ${igo_dir}/imgui_impl_opengl3.h
+  ${igo_dir}/imgui_impl_glfw.cpp ${igo_dir}/imgui_impl_opengl3.cpp
+  )
+target_compile_definitions(imgui-glfw-gl3 PUBLIC -DIMGUI_IMPL_OPENGL_LOADER_GLAD)
+target_include_directories(imgui-glfw-gl3 PUBLIC ${igo_dir})
+target_link_libraries(imgui-glfw-gl3 PUBLIC
+  ${GLFW_LIBRARIES} ${OPENGL_LIBRARIES} glad imgui
+  )
+
+
+# Client (Nuklear, default)
 #target_include_directories(client "${PROJECT_SOURCE_DIR}/src/client")
 add_executable(client ${PROJECT_SOURCE_DIR}/src/client/client.cpp)
 target_include_directories(client PUBLIC ${GLFW_INCLUDE_DIRS} ${GLUT_INCLUDE_DIR} ${OPENGL_INCLUDE_DIRS} ${NUKLEAR_INCLUDE_DIR} ${GLAD_INCLUDE_DIRS})
 target_link_libraries(client ${GLFW_LIBRARIES} ${GLUT_LIBRARY}
   ${OPENGL_LIBRARIES} ${GLAD_LIBRARIES} ${CMAKE_DL_LIBS})
 
+# Client (Imgui)
+add_executable(client_imgui ${PROJECT_SOURCE_DIR}/src/client/client_imgui.cpp)
+target_compile_definitions(client_imgui PUBLIC -DIMGUI_IMPL_OPENGL_LOADER_GLAD)
+target_include_directories(client_imgui PUBLIC ${GLFW_INCLUDE_DIRS} ${GLUT_INCLUDE_DIR} ${OPENGL_INCLUDE_DIRS} ${GLAD_INCLUDE_DIRS} ${imgui_dir} ${igo_dir})
+target_link_libraries(client_imgui ${GLFW_LIBRARIES} ${GLUT_LIBRARY}
+  ${OPENGL_LIBRARIES} ${GLAD_LIBRARIES} ${CMAKE_DL_LIBS} imgui imgui-glfw-gl3)
+
 # Server
 #target_include_directories(server "${PROJECT_SOURCE_DIR}/src/server")
 add_executable(server ${PROJECT_SOURCE_DIR}/src/server/server.cpp)

src/client/client_imgui.cpp

@@ -0,0 +1,111 @@
+#include <math.h>
+#include <stdio.h>
+#include <string.h>
+
+#include "imgui.h"
+#include "imgui_impl_glfw.h"
+#include "imgui_impl_opengl3.h"
+
+#include <glad/glad.h>
+#include <GLFW/glfw3.h>
+
+static void error_callback(int error, const char* description)
+{
+   fprintf(stderr, "Error %d: %s\n", error, description);
+}
+
+int main(int argc, char** argv)
+{
+    GLFWwindow* window;
+
+    /* Initialize the library */
+    glfwSetErrorCallback(error_callback);
+    if (!glfwInit()) {
+       fprintf(stdout, "[GFLW] Error: failed to init!\n");
+       return -1;
+    }
+
+    /* Create a windowed mode window and its OpenGL context */
+    glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
+    glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 0);
+    window = glfwCreateWindow(1024, 768, "Client", NULL, NULL);
+    glfwSetWindowAttrib(window, GLFW_DECORATED, GLFW_TRUE);
+    if (!window) {
+        glfwTerminate();
+        return -1;
+    }
+    glfwMakeContextCurrent(window);
+    glfwSwapInterval(1); // Vsync
+
+    if (!gladLoadGL()) {
+       fprintf(stderr, "[GLAD] Error loading\n");
+       return 1;
+    }
+
+    // Setup Dear ImGui context
+    IMGUI_CHECKVERSION();
+    ImGui::CreateContext();
+    ImGuiIO& io = ImGui::GetIO(); (void)io;
+    //io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;     // Enable Keyboard Controls
+    //io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad;      // Enable Gamepad Controls
+
+    // Setup Dear ImGui style
+    ImGui::StyleColorsDark();
+    //ImGui::StyleColorsClassic();
+
+    // Setup Platform/Renderer bindings
+    ImGui_ImplGlfw_InitForOpenGL(window, true);
+    ImGui_ImplOpenGL3_Init("#version 130");
+
+    int height = 0, width = 0;
+    ImVec4 clear_color = ImVec4(0.45f, 0.55f, 0.60f, 1.00f);
+    while(!glfwWindowShouldClose(window)) {
+       glfwPollEvents();
+       // Process input.
+
+       // Start the Dear ImGui frame
+       ImGui_ImplOpenGL3_NewFrame();
+       ImGui_ImplGlfw_NewFrame();
+       ImGui::NewFrame();
+
+       {
+          static float f = 0.0f;
+          static int counter = 0;
+
+          ImGui::Begin("Hello, world!");                          // Create a window called "Hello, world!" and append into it.
+
+          ImGui::Text("This is some useful text.");               // Display some text (you can use a format strings too)
+
+          ImGui::SliderFloat("float", &f, 0.0f, 1.0f);            // Edit 1 float using a slider from 0.0f to 1.0f
+          ImGui::ColorEdit3("clear color", (float*)&clear_color); // Edit 3 floats representing a color
+
+          if (ImGui::Button("Button")) {                            // Buttons return true when clicked (most widgets return true when edited/activated)
+             counter++;
+          }
+          ImGui::SameLine();
+          ImGui::Text("counter = %d", counter);
+
+          ImGui::Text("Application average %.3f ms/frame (%.1f FPS)", 1000.0f / ImGui::GetIO().Framerate, ImGui::GetIO().Framerate);
+          ImGui::End();
+       }
+       // @TODO Game tick
+
+       // Rendering
+       ImGui::Render();
+       int display_w, display_h;
+       glfwGetFramebufferSize(window, &display_w, &display_h);
+       glViewport(0, 0, display_w, display_h);
+       glClearColor(clear_color.x, clear_color.y, clear_color.z, clear_color.w);
+       glClear(GL_COLOR_BUFFER_BIT);
+       ImGui_ImplOpenGL3_RenderDrawData(ImGui::GetDrawData());
+       glfwSwapBuffers(window);
+    }
+
+    // Cleanup
+    ImGui_ImplOpenGL3_Shutdown();
+    ImGui_ImplGlfw_Shutdown();
+    ImGui::DestroyContext();
+
+    glfwTerminate();
+    return 0;
+}