h2-mod/deps/imgui/examples/example_android_opengl3/main.cpp
2024-03-07 03:33:59 -05:00

370 lines
14 KiB
C++

// dear imgui: standalone example application for Android + OpenGL ES 3
// If you are new to dear imgui, see examples/README.txt and documentation at the top of imgui.cpp.
#include "imgui.h"
#include "imgui_impl_android.h"
#include "imgui_impl_opengl3.h"
#include <android/log.h>
#include <android_native_app_glue.h>
#include <android/asset_manager.h>
#include <EGL/egl.h>
#include <GLES3/gl3.h>
// Data
static EGLDisplay g_EglDisplay = EGL_NO_DISPLAY;
static EGLSurface g_EglSurface = EGL_NO_SURFACE;
static EGLContext g_EglContext = EGL_NO_CONTEXT;
static struct android_app* g_App = NULL;
static bool g_Initialized = false;
static char g_LogTag[] = "ImGuiExample";
// Forward declarations of helper functions
static int ShowSoftKeyboardInput();
static int PollUnicodeChars();
static int GetAssetData(const char* filename, void** out_data);
void init(struct android_app* app)
{
if (g_Initialized)
return;
g_App = app;
ANativeWindow_acquire(g_App->window);
// Initialize EGL
// This is mostly boilerplate code for EGL...
{
g_EglDisplay = eglGetDisplay(EGL_DEFAULT_DISPLAY);
if (g_EglDisplay == EGL_NO_DISPLAY)
__android_log_print(ANDROID_LOG_ERROR, g_LogTag, "%s", "eglGetDisplay(EGL_DEFAULT_DISPLAY) returned EGL_NO_DISPLAY");
if (eglInitialize(g_EglDisplay, 0, 0) != EGL_TRUE)
__android_log_print(ANDROID_LOG_ERROR, g_LogTag, "%s", "eglInitialize() returned with an error");
const EGLint egl_attributes[] = { EGL_BLUE_SIZE, 8, EGL_GREEN_SIZE, 8, EGL_RED_SIZE, 8, EGL_DEPTH_SIZE, 24, EGL_SURFACE_TYPE, EGL_WINDOW_BIT, EGL_NONE };
EGLint num_configs = 0;
if (eglChooseConfig(g_EglDisplay, egl_attributes, nullptr, 0, &num_configs) != EGL_TRUE)
__android_log_print(ANDROID_LOG_ERROR, g_LogTag, "%s", "eglChooseConfig() returned with an error");
if (num_configs == 0)
__android_log_print(ANDROID_LOG_ERROR, g_LogTag, "%s", "eglChooseConfig() returned 0 matching config");
// Get the first matching config
EGLConfig egl_config;
eglChooseConfig(g_EglDisplay, egl_attributes, &egl_config, 1, &num_configs);
EGLint egl_format;
eglGetConfigAttrib(g_EglDisplay, egl_config, EGL_NATIVE_VISUAL_ID, &egl_format);
ANativeWindow_setBuffersGeometry(g_App->window, 0, 0, egl_format);
const EGLint egl_context_attributes[] = { EGL_CONTEXT_CLIENT_VERSION, 3, EGL_NONE };
g_EglContext = eglCreateContext(g_EglDisplay, egl_config, EGL_NO_CONTEXT, egl_context_attributes);
if (g_EglContext == EGL_NO_CONTEXT)
__android_log_print(ANDROID_LOG_ERROR, g_LogTag, "%s", "eglCreateContext() returned EGL_NO_CONTEXT");
g_EglSurface = eglCreateWindowSurface(g_EglDisplay, egl_config, g_App->window, NULL);
eglMakeCurrent(g_EglDisplay, g_EglSurface, g_EglSurface, g_EglContext);
}
// Setup Dear ImGui context
IMGUI_CHECKVERSION();
ImGui::CreateContext();
ImGuiIO& io = ImGui::GetIO();
// Disable loading/saving of .ini file from disk.
// FIXME: Consider using LoadIniSettingsFromMemory() / SaveIniSettingsToMemory() to save in appropriate location for Android.
io.IniFilename = NULL;
// Setup Dear ImGui style
ImGui::StyleColorsDark();
//ImGui::StyleColorsClassic();
// Setup Platform/Renderer backends
ImGui_ImplAndroid_Init(g_App->window);
ImGui_ImplOpenGL3_Init("#version 300 es");
// Load Fonts
// - If no fonts are loaded, dear imgui will use the default font. You can also load multiple fonts and use ImGui::PushFont()/PopFont() to select them.
// - If the file cannot be loaded, the function will return NULL. Please handle those errors in your application (e.g. use an assertion, or display an error and quit).
// - 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 'docs/FONTS.md' 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 \\ !
// - Android: The TTF files have to be placed into the assets/ directory (android/app/src/main/assets), we use our GetAssetData() helper to retrieve them.
// We load the default font with increased size to improve readability on many devices with "high" DPI.
// FIXME: Put some effort into DPI awareness.
// Important: when calling AddFontFromMemoryTTF(), ownership of font_data is transfered by Dear ImGui by default (deleted is handled by Dear ImGui), unless we set FontDataOwnedByAtlas=false in ImFontConfig
ImFontConfig font_cfg;
font_cfg.SizePixels = 22.0f;
io.Fonts->AddFontDefault(&font_cfg);
//void* font_data;
//int font_data_size;
//ImFont* font;
//font_data_size = GetAssetData("Roboto-Medium.ttf", &font_data);
//font = io.Fonts->AddFontFromMemoryTTF(font_data, font_data_size, 16.0f);
//IM_ASSERT(font != NULL);
//font_data_size = GetAssetData("Cousine-Regular.ttf", &font_data);
//font = io.Fonts->AddFontFromMemoryTTF(font_data, font_data_size, 15.0f);
//IM_ASSERT(font != NULL);
//font_data_size = GetAssetData("DroidSans.ttf", &font_data);
//font = io.Fonts->AddFontFromMemoryTTF(font_data, font_data_size, 16.0f);
//IM_ASSERT(font != NULL);
//font_data_size = GetAssetData("ProggyTiny.ttf", &font_data);
//font = io.Fonts->AddFontFromMemoryTTF(font_data, font_data_size, 10.0f);
//IM_ASSERT(font != NULL);
//font_data_size = GetAssetData("ArialUni.ttf", &font_data);
//font = io.Fonts->AddFontFromMemoryTTF(font_data, font_data_size, 18.0f, NULL, io.Fonts->GetGlyphRangesJapanese());
//IM_ASSERT(font != NULL);
// Arbitrary scale-up
// FIXME: Put some effort into DPI awareness
ImGui::GetStyle().ScaleAllSizes(3.0f);
g_Initialized = true;
}
void tick()
{
ImGuiIO& io = ImGui::GetIO();
if (g_EglDisplay == EGL_NO_DISPLAY)
return;
// Our state
static bool show_demo_window = true;
static bool show_another_window = false;
static ImVec4 clear_color = ImVec4(0.45f, 0.55f, 0.60f, 1.00f);
// Poll Unicode characters via JNI
// FIXME: do not call this every frame because of JNI overhead
PollUnicodeChars();
// Open on-screen (soft) input if requested by Dear ImGui
static bool WantTextInputLast = false;
if (io.WantTextInput && !WantTextInputLast)
ShowSoftKeyboardInput();
WantTextInputLast = io.WantTextInput;
// Start the Dear ImGui frame
ImGui_ImplOpenGL3_NewFrame();
ImGui_ImplAndroid_NewFrame();
ImGui::NewFrame();
// 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 created 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 / ImGui::GetIO().Framerate, ImGui::GetIO().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());
eglSwapBuffers(g_EglDisplay, g_EglSurface);
}
void shutdown()
{
if (!g_Initialized)
return;
// Cleanup
ImGui_ImplOpenGL3_Shutdown();
ImGui_ImplAndroid_Shutdown();
ImGui::DestroyContext();
if (g_EglDisplay != EGL_NO_DISPLAY)
{
eglMakeCurrent(g_EglDisplay, EGL_NO_SURFACE, EGL_NO_SURFACE, EGL_NO_CONTEXT);
if (g_EglContext != EGL_NO_CONTEXT)
eglDestroyContext(g_EglDisplay, g_EglContext);
if (g_EglSurface != EGL_NO_SURFACE)
eglDestroySurface(g_EglDisplay, g_EglSurface);
eglTerminate(g_EglDisplay);
}
g_EglDisplay = EGL_NO_DISPLAY;
g_EglContext = EGL_NO_CONTEXT;
g_EglSurface = EGL_NO_SURFACE;
ANativeWindow_release(g_App->window);
g_Initialized = false;
}
static void handleAppCmd(struct android_app* app, int32_t appCmd)
{
switch (appCmd)
{
case APP_CMD_SAVE_STATE:
break;
case APP_CMD_INIT_WINDOW:
init(app);
break;
case APP_CMD_TERM_WINDOW:
shutdown();
break;
case APP_CMD_GAINED_FOCUS:
break;
case APP_CMD_LOST_FOCUS:
break;
}
}
static int32_t handleInputEvent(struct android_app* app, AInputEvent* inputEvent)
{
return ImGui_ImplAndroid_HandleInputEvent(inputEvent);
}
void android_main(struct android_app* app)
{
app->onAppCmd = handleAppCmd;
app->onInputEvent = handleInputEvent;
while (true)
{
int out_events;
struct android_poll_source* out_data;
// Poll all events. If the app is not visible, this loop blocks until g_Initialized == true.
while (ALooper_pollAll(g_Initialized ? 0 : -1, NULL, &out_events, (void**)&out_data) >= 0)
{
// Process one event
if (out_data != NULL)
out_data->process(app, out_data);
// Exit the app by returning from within the infinite loop
if (app->destroyRequested != 0)
{
// shutdown() should have been called already while processing the
// app command APP_CMD_TERM_WINDOW. But we play save here
if (!g_Initialized)
shutdown();
return;
}
}
// Initiate a new frame
tick();
}
}
// Unfortunately, there is no way to show the on-screen input from native code.
// Therefore, we call ShowSoftKeyboardInput() of the main activity implemented in MainActivity.kt via JNI.
static int ShowSoftKeyboardInput()
{
JavaVM* java_vm = g_App->activity->vm;
JNIEnv* java_env = NULL;
jint jni_return = java_vm->GetEnv((void**)&java_env, JNI_VERSION_1_6);
if (jni_return == JNI_ERR)
return -1;
jni_return = java_vm->AttachCurrentThread(&java_env, NULL);
if (jni_return != JNI_OK)
return -2;
jclass native_activity_clazz = java_env->GetObjectClass(g_App->activity->clazz);
if (native_activity_clazz == NULL)
return -3;
jmethodID method_id = java_env->GetMethodID(native_activity_clazz, "showSoftInput", "()V");
if (method_id == NULL)
return -4;
java_env->CallVoidMethod(g_App->activity->clazz, method_id);
jni_return = java_vm->DetachCurrentThread();
if (jni_return != JNI_OK)
return -5;
return 0;
}
// Unfortunately, the native KeyEvent implementation has no getUnicodeChar() function.
// Therefore, we implement the processing of KeyEvents in MainActivity.kt and poll
// the resulting Unicode characters here via JNI and send them to Dear ImGui.
static int PollUnicodeChars()
{
JavaVM* java_vm = g_App->activity->vm;
JNIEnv* java_env = NULL;
jint jni_return = java_vm->GetEnv((void**)&java_env, JNI_VERSION_1_6);
if (jni_return == JNI_ERR)
return -1;
jni_return = java_vm->AttachCurrentThread(&java_env, NULL);
if (jni_return != JNI_OK)
return -2;
jclass native_activity_clazz = java_env->GetObjectClass(g_App->activity->clazz);
if (native_activity_clazz == NULL)
return -3;
jmethodID method_id = java_env->GetMethodID(native_activity_clazz, "pollUnicodeChar", "()I");
if (method_id == NULL)
return -4;
// Send the actual characters to Dear ImGui
ImGuiIO& io = ImGui::GetIO();
jint unicode_character;
while ((unicode_character = java_env->CallIntMethod(g_App->activity->clazz, method_id)) != 0)
io.AddInputCharacter(unicode_character);
jni_return = java_vm->DetachCurrentThread();
if (jni_return != JNI_OK)
return -5;
return 0;
}
// Helper to retrieve data placed into the assets/ directory (android/app/src/main/assets)
static int GetAssetData(const char* filename, void** outData)
{
int num_bytes = 0;
AAsset* asset_descriptor = AAssetManager_open(g_App->activity->assetManager, filename, AASSET_MODE_BUFFER);
if (asset_descriptor)
{
num_bytes = AAsset_getLength(asset_descriptor);
*outData = IM_ALLOC(num_bytes);
int64_t num_bytes_read = AAsset_read(asset_descriptor, *outData, num_bytes);
AAsset_close(asset_descriptor);
IM_ASSERT(num_bytes_read == num_bytes);
}
return num_bytes;
}