Examples: SDL+GL3: Added Navigation keyboard mapping. (#787)

examples/sdl_opengl3_example/imgui_impl_sdl_gl3.cpp

@@ -4,6 +4,7 @@
 
 // Implemented features:
 //  [X] User texture binding. Cast 'GLuint' OpenGL texture identifier as void*/ImTextureID. Read the FAQ about ImTextureID in imgui.cpp.
+//  [X] Keyboard navigation mapping. Enable with 'io.NavFlags |= ImGuiNavFlags_EnableKeyboard'.
 
 // You can copy and use unmodified imgui_impl_* files in your project. See main.cpp for an example of using this.
 // If you use this binding you'll need to call 4 functions: ImGui_ImplXXXX_Init(), ImGui_ImplXXXX_NewFrame(), ImGui::Render() and ImGui_ImplXXXX_Shutdown().
@@ -412,6 +413,29 @@ void ImGui_ImplSdlGL3_NewFrame(SDL_Window* window)
     // Hide OS mouse cursor if ImGui is drawing it
     SDL_ShowCursor(io.MouseDrawCursor ? 0 : 1);
 
+    // Gamepad/keyboard navigation mapping [BETA]
+    memset(io.NavInputs, 0, sizeof(io.NavInputs));
+    if (io.NavFlags & ImGuiNavFlags_EnableKeyboard)
+    {
+        // Update keyboard
+        // FIXME-NAV: We are still using some of the ImGuiNavInput_PadXXX enums as keyboard support is incomplete.
+        #define MAP_KEY(NAV_NO, KEY_NO) { if (io.KeysDown[KEY_NO]) io.NavInputs[NAV_NO] = 1.0f; }
+        MAP_KEY(ImGuiNavInput_KeyLeft,      SDL_SCANCODE_LEFT);
+        MAP_KEY(ImGuiNavInput_KeyRight,     SDL_SCANCODE_RIGHT);
+        MAP_KEY(ImGuiNavInput_KeyUp,        SDL_SCANCODE_UP);
+        MAP_KEY(ImGuiNavInput_KeyDown,      SDL_SCANCODE_DOWN);
+        MAP_KEY(ImGuiNavInput_KeyMenu,      SDL_SCANCODE_LALT);
+        MAP_KEY(ImGuiNavInput_KeyMenu,      SDL_SCANCODE_RALT);
+        MAP_KEY(ImGuiNavInput_PadActivate,  SDL_SCANCODE_SPACE);
+        MAP_KEY(ImGuiNavInput_PadCancel,    SDL_SCANCODE_ESCAPE);
+        MAP_KEY(ImGuiNavInput_PadInput,     SDL_SCANCODE_RETURN);
+        MAP_KEY(ImGuiNavInput_PadTweakSlow, SDL_SCANCODE_LALT);
+        MAP_KEY(ImGuiNavInput_PadTweakSlow, SDL_SCANCODE_LALT);
+        MAP_KEY(ImGuiNavInput_PadTweakFast, SDL_SCANCODE_LSHIFT);
+        MAP_KEY(ImGuiNavInput_PadTweakFast, SDL_SCANCODE_RSHIFT);
+        #undef MAP_KEY
+    }
+
     // Start the frame. This call will update the io.WantCaptureMouse, io.WantCaptureKeyboard flag that you can use to dispatch inputs (or not) to your application.
     ImGui::NewFrame();
 }

examples/sdl_opengl3_example/imgui_impl_sdl_gl3.h

@@ -4,6 +4,7 @@
 
 // Implemented features:
 //  [X] User texture binding. Cast 'GLuint' OpenGL texture identifier as void*/ImTextureID. Read the FAQ about ImTextureID in imgui.cpp.
+//  [X] Keyboard navigation mapping. Enable with 'io.NavFlags |= ImGuiNavFlags_EnableKeyboard'.
 
 // You can copy and use unmodified imgui_impl_* files in your project. See main.cpp for an example of using this.
 // If you use this binding you'll need to call 4 functions: ImGui_ImplXXXX_Init(), ImGui_ImplXXXX_NewFrame(), ImGui::Render() and ImGui_ImplXXXX_Shutdown().

examples/sdl_opengl3_example/main.cpp

@@ -34,7 +34,9 @@ int main(int, char**)
     gl3wInit();
 
     // Setup ImGui binding
+    ImGuiIO& io = ImGui::GetIO(); (void)io;
     ImGui_ImplSdlGL3_Init(window);
+    //io.NavFlags |= ImGuiNavFlags_EnableKeyboard;
 
     // Setup style
     ImGui::StyleColorsDark();
@@ -47,7 +49,6 @@ int main(int, char**)
     // - The fonts will be rasterized at a given size (w/ oversampling) and stored into a texture when calling ImFontAtlas::Build()/GetTexDataAsXXXX(), which ImGui_ImplXXXX_NewFrame below will call.
     // - Read 'misc/fonts/README.txt' for more instructions and details.
     // - Remember that in C/C++ if you want to include a backslash \ in a string literal you need to write a double backslash \\ !
-    //ImGuiIO& io = ImGui::GetIO();
     //io.Fonts->AddFontDefault();
     //io.Fonts->AddFontFromFileTTF("../../misc/fonts/Roboto-Medium.ttf", 16.0f);
     //io.Fonts->AddFontFromFileTTF("../../misc/fonts/Cousine-Regular.ttf", 15.0f);