optimized main loop and split it into parts

imgui

@@ -1 +1 @@
-Subproject commit 3e08a7e76e7e275e90d22d9081c01e0515d187b0
+Subproject commit 9e129571c74f68a954916a3d857a43698df3a51f

src/gui/demo_ui.cpp

@@ -0,0 +1,45 @@
+#include "gui_internal.hpp"
+
+bool show_demo_window = true;
+bool show_another_window = false;
+
+Maybe demo_ui_draw(ImGuiIO& io){
+    // 1. Show the big demo window (Most of the sample code is in ImGui::ShowDemoWindow()! You can browse its code to learn more about Dear ImGui!).
+    if (show_demo_window)
+        ImGui::ShowDemoWindow(&show_demo_window);
+
+    // 2. Show a simple window that we create ourselves. We use a Begin/End pair to create a named window.
+    {
+        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::Checkbox("Demo Window", &show_demo_window);      // Edit bools storing our window open/close state
+        ImGui::Checkbox("Another Window", &show_another_window);
+
+        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 / io.Framerate, io.Framerate);
+        ImGui::End();
+    }
+
+    // 3. Show another simple window.
+    if (show_another_window)
+    {
+        ImGui::Begin("Another Window", &show_another_window);   // Pass a pointer to our bool variable (the window will have a closing button that will clear the bool when clicked)
+        ImGui::Text("Hello from another window!");
+        if (ImGui::Button("Close Me"))
+            show_another_window = false;
+        ImGui::End();
+    }
+
+    return MaybeNull;
+}

src/gui/gui.h

@@ -6,7 +6,7 @@ extern "C" {
 
 #include "../../kerep/src/base/base.h"
 
-Maybe main_window_open();
+Maybe main_window_open(const char* window_title);
 Maybe main_window_loop_start();
 Maybe main_window_close();
 

src/gui/gui_internal.hpp

@@ -6,3 +6,10 @@
 #include "../../imgui/imgui.h"
 #include "../../imgui/backends/imgui_impl_sdl2.h"
 #include "../../imgui/backends/imgui_impl_opengl3.h"
+
+const u8 frame_rate_max=60; // frames per second
+extern ImVec4 clear_color; // background color for main window
+
+/// @brief frees all allocated resources
+void main_window_destroy();
+Maybe demo_ui_draw(ImGuiIO&);

src/gui/main_window.cpp

@@ -1,6 +1,6 @@
 #include "gui_internal.hpp"
 
-const char* window_title="GraphC";
+ImVec4 clear_color = RGBAHexToF(35,35,50,255);
 bool loop_running=false;
 SDL_Window* sdl_window;
 SDL_GLContext gl_context;
@@ -11,8 +11,9 @@ SDL_GLContext gl_context;
     SDL_ClearError(); \
 }
 #define SDL_TRY_ZERO(FUNC_CALL) if(FUNC_CALL != 0) SDL_ERROR_SAFETHROW();
+#define SDL_TRY_ONE(FUNC_CALL) if(FUNC_CALL != 1) SDL_ERROR_SAFETHROW();
 
-Maybe main_window_open(){
+Maybe main_window_open(const char* window_title){
     SDL_TRY_ZERO(SDL_Init(SDL_INIT_VIDEO));
     // GL 3.0 + GLSL 130
     const char* glsl_version = "#version 130";
@@ -46,8 +47,11 @@ Maybe main_window_open(){
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad;    // Enable Gamepad Controls
     io.ConfigFlags |= ImGuiConfigFlags_DockingEnable;       // Enable Docking
     io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable;     // Enable Multi-Viewport / Platform Windows
-    io.ConfigViewportsNoDecoration=false;
+    io.ConfigDockingTransparentPayload = true;
-    
+    io.ConfigInputTextCursorBlink = false;
+    io.ConfigViewportsNoTaskBarIcon = true;
+    io.ConfigWindowsMoveFromTitleBarOnly = true;
+
     // Setup Dear ImGui style
     ImGui::StyleColorsDark();
     
@@ -68,109 +72,99 @@ Maybe main_window_open(){
     return MaybeNull;
 }
 
+// Wait, poll and handle events (inputs, window resize, etc.)
+// You can read the io.WantCaptureMouse, io.WantCaptureKeyboard flags to tell if dear imgui wants to use your inputs.
+// - When io.WantCaptureMouse is true, do not dispatch mouse input data to your main application, or clear/overwrite your copy of the mouse data.
+// - When io.WantCaptureKeyboard is true, do not dispatch keyboard input data to your main application, or clear/overwrite your copy of the keyboard data.
+// Generally you may always pass all inputs to dear imgui, and hide them from your application based on those two flags.
+Maybe poll_events(bool& frame_needs_update, bool wait){
+    SDL_Event event;
+    if(wait){
+        // waits for first event in cpu-efficient way
+        SDL_TRY_ONE(SDL_WaitEvent(&event)); 
+    }
+    // doesnt wait for event
+    else if(!SDL_PollEvent(&event))
+        return MaybeNull;
+    
+    do {
+        frame_needs_update|=ImGui_ImplSDL2_ProcessEvent(&event);
+        switch(event.type){
+            case SDL_QUIT: {
+                try_cpp(main_window_close(),_9914,;);
+                break;
+            }
+            case SDL_WINDOWEVENT: {
+                if(event.window.event == SDL_WINDOWEVENT_CLOSE && event.window.windowID == SDL_GetWindowID(sdl_window)){
+                    try_cpp(main_window_close(),_9915,;);
+                }
+                break;
+            }
+        }
+    } while (SDL_PollEvent(&event)); // if there are more events, handles them
+    return MaybeNull;
+}
+
+Maybe draw_frame(){
+    // Start the Dear ImGui frame
+    ImGui_ImplOpenGL3_NewFrame();
+    ImGui_ImplSDL2_NewFrame();
+    ImGui::NewFrame();
+    ImGuiIO& io = ImGui::GetIO();
+
+    // Draw UI
+    try_cpp(demo_ui_draw(io), _5218, ;);
+
+    // Rendering
+    ImGui::Render();
+    glViewport(0, 0, (int)io.DisplaySize.x, (int)io.DisplaySize.y);
+    glClearColor(clear_color.x * clear_color.w, clear_color.y * clear_color.w, clear_color.z * clear_color.w, clear_color.w);
+    glClear(GL_COLOR_BUFFER_BIT);
+    ImGui_ImplOpenGL3_RenderDrawData(ImGui::GetDrawData());
+
+    // Update and Render additional Platform Windows
+    // (Platform functions may change the current OpenGL context, so we save/restore it to make it easier to paste this code elsewhere.
+    //  For this specific demo app we could also call SDL_GL_MakeCurrent(window, gl_context) directly)
+    if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
+    {
+        SDL_Window* backup_current_window = SDL_GL_GetCurrentWindow();
+        SDL_GLContext backup_current_context = SDL_GL_GetCurrentContext();
+        ImGui::UpdatePlatformWindows();
+        ImGui::RenderPlatformWindowsDefault();
+        SDL_GL_MakeCurrent(backup_current_window, backup_current_context);
+    }
+
+    SDL_GL_SwapWindow(sdl_window);
+
+    return MaybeNull;
+}
+
 Maybe main_window_loop_start(){
     if(loop_running)
         safethrow_msg("loop is already running",;);
-    loop_running=true;
 
-    // Our state
+    // draw first frame
-    bool show_demo_window = true;
+    try_cpp(draw_frame(),_2175,;);
-    bool show_another_window = false;
-    ImVec4 clear_color = RGBAHexToF(35,35,50,255);
 
     // main loop
+    loop_running=true;
     while(loop_running){
-        // Poll and handle events (inputs, window resize, etc.)
+        bool frame_needs_update=false;
-        // You can read the io.WantCaptureMouse, io.WantCaptureKeyboard flags to tell if dear imgui wants to use your inputs.
+        // waits for events
-        // - When io.WantCaptureMouse is true, do not dispatch mouse input data to your main application, or clear/overwrite your copy of the mouse data.
+        try_cpp(poll_events(frame_needs_update, true),_55415,;);
-        // - When io.WantCaptureKeyboard is true, do not dispatch keyboard input data to your main application, or clear/overwrite your copy of the keyboard data.
-        // Generally you may always pass all inputs to dear imgui, and hide them from your application based on those two flags.
-        SDL_Event event;
-        while (SDL_PollEvent(&event))
-        {
-            ImGui_ImplSDL2_ProcessEvent(&event);
-            if (event.type == SDL_QUIT){
-                try_cpp(main_window_close(),_9914,;);
-            }
-            if (event.type==SDL_WINDOWEVENT && event.window.event == SDL_WINDOWEVENT_CLOSE && event.window.windowID == SDL_GetWindowID(sdl_window)){
-                try_cpp(main_window_close(),_9915,;);
-            }
-        }
 
-        // Start the Dear ImGui frame
+        if(!frame_needs_update){
-        ImGui_ImplOpenGL3_NewFrame();
+            // skips frame rendering if user didn't interacted with anything
-        ImGui_ImplSDL2_NewFrame();
+            u32 frame_delay_ms=1000/frame_rate_max;
-        ImGui::NewFrame();
+            SDL_Delay(frame_delay_ms);
+            continue;
+        }
         
-        ImGuiIO& io = ImGui::GetIO(); (void)io;
+        try_cpp(draw_frame(),_2175,;);
-
-        // 1. Show the big demo window (Most of the sample code is in ImGui::ShowDemoWindow()! You can browse its code to learn more about Dear ImGui!).
-        if (show_demo_window)
-            ImGui::ShowDemoWindow(&show_demo_window);
-
-        // 2. Show a simple window that we create ourselves. We use a Begin/End pair to create a named window.
-        {
-            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::Checkbox("Demo Window", &show_demo_window);      // Edit bools storing our window open/close state
-            ImGui::Checkbox("Another Window", &show_another_window);
-
-            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 / io.Framerate, io.Framerate);
-            ImGui::End();
-        }
-
-        // 3. Show another simple window.
-        if (show_another_window)
-        {
-            ImGui::Begin("Another Window", &show_another_window);   // Pass a pointer to our bool variable (the window will have a closing button that will clear the bool when clicked)
-            ImGui::Text("Hello from another window!");
-            if (ImGui::Button("Close Me"))
-                show_another_window = false;
-            ImGui::End();
-        }
-
-        // Rendering
-        ImGui::Render();
-        glViewport(0, 0, (int)io.DisplaySize.x, (int)io.DisplaySize.y);
-        glClearColor(clear_color.x * clear_color.w, clear_color.y * clear_color.w, clear_color.z * clear_color.w, clear_color.w);
-        glClear(GL_COLOR_BUFFER_BIT);
-        ImGui_ImplOpenGL3_RenderDrawData(ImGui::GetDrawData());
-
-        // Update and Render additional Platform Windows
-        // (Platform functions may change the current OpenGL context, so we save/restore it to make it easier to paste this code elsewhere.
-        //  For this specific demo app we could also call SDL_GL_MakeCurrent(window, gl_context) directly)
-        if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
-        {
-            SDL_Window* backup_current_window = SDL_GL_GetCurrentWindow();
-            SDL_GLContext backup_current_context = SDL_GL_GetCurrentContext();
-            ImGui::UpdatePlatformWindows();
-            ImGui::RenderPlatformWindowsDefault();
-            SDL_GL_MakeCurrent(backup_current_window, backup_current_context);
-        }
-
-        SDL_GL_SwapWindow(sdl_window);
     }
 
     // Cleanup
-    ImGui_ImplOpenGL3_Shutdown();
+    main_window_destroy();
-    ImGui_ImplSDL2_Shutdown();
-    ImGui::DestroyContext();
-    SDL_GL_DeleteContext(gl_context);
-    SDL_DestroyWindow(sdl_window);
-    SDL_Quit();
-
     return MaybeNull;
 }
 
@@ -178,6 +172,14 @@ Maybe main_window_close(){
     if(!loop_running)
         return MaybeNull;
     loop_running=false;
-    
     return MaybeNull;
 }
+
+void main_window_destroy(){
+    ImGui_ImplOpenGL3_Shutdown();
+    ImGui_ImplSDL2_Shutdown();
+    ImGui::DestroyContext();
+    SDL_GL_DeleteContext(gl_context);
+    SDL_DestroyWindow(sdl_window);
+    SDL_Quit();
+}

src/main.c

@@ -19,7 +19,7 @@ int main(const int argc, const char* const* argv){
         kprintf(" %s", argv[i]);
     kprintf("\n");
 
-    tryLast(main_window_open(),_1);
+    tryLast(main_window_open("GraphC"),_1);
     tryLast(main_window_loop_start(),_2);
     tryLast(main_window_close(),_3);