Add setup.sh script to build android from SDL3 repo

Add README

Author: zmertens

examples/example_android_sdl3_opengl3/DearImGuiDemo.cpp

@@ -0,0 +1,197 @@
+// dear imgui: standalone example application for Android + SDL3 + OpenGLES
+// If you are new to dear imgui, see examples/README.txt and documentation at the top of imgui.cpp.
+// (SDL is a cross-platform general purpose library for handling windows, inputs, OpenGL/Vulkan graphics context creation, etc.)
+
+// **THIS CODE USES MODERN OPENGL (SHADERS, VBO, VAO, etc.)**
+// **Prefer using the code in the example_sdl_opengl3/ folder**
+// See imgui_impl_sdl.cpp for details.
+
+// SDL/test/testgles.c was used as a reference guide
+
+#include <string.h>
+#include <stdlib.h>
+
+#include <SDL3/SDL_main.h>
+#include <SDL3/SDL_test_common.h>
+
+#include <EGL/egl.h>
+#include <GLES3/gl3.h>
+#include <SDL3/SDL_opengles.h>
+
+#include "imgui.h"
+#include "imgui_impl_opengl3.h"
+#include "imgui_impl_sdl3.h"
+
+
+// Must use conventional parameters here
+// or else there will be an undefined reference to SDL_main
+int main(int argc, char** argv)
+{
+    // Setup SDL
+    if (SDL_Init(SDL_INIT_VIDEO | SDL_INIT_TIMER) != 0)
+    {
+        SDL_LogError(SDL_LOG_CATEGORY_ERROR, "Error: %s\n", SDL_GetError());
+        return EXIT_FAILURE;
+    }
+
+    SDL_LogSetAllPriority(SDL_LOG_PRIORITY_VERBOSE);
+
+    // Setup window
+    SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);
+    SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE, 24);
+    SDL_GL_SetAttribute(SDL_GL_STENCIL_SIZE, 8);
+    SDL_GL_SetAttribute(SDL_GL_BUFFER_SIZE, 32);
+    SDL_GL_SetAttribute(SDL_GL_RED_SIZE, 8);
+    SDL_GL_SetAttribute(SDL_GL_GREEN_SIZE, 8);
+    SDL_GL_SetAttribute(SDL_GL_BLUE_SIZE, 8);
+    SDL_GL_SetAttribute(SDL_GL_ALPHA_SIZE, 8);
+    SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 3);
+    SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 0);
+    SDL_GL_SetAttribute(SDL_GL_CONTEXT_FLAGS, 0);
+    SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_ES);
+
+    // Create window with graphics context
+    SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);
+    SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE, 24);
+    SDL_GL_SetAttribute(SDL_GL_STENCIL_SIZE, 8);
+    Uint32 window_flags = SDL_WINDOW_OPENGL | SDL_WINDOW_RESIZABLE | SDL_WINDOW_HIDDEN;
+    SDL_Window* window = SDL_CreateWindow("Dear ImGui SDL3+OpenGL3 example", 1280, 720, window_flags);
+    if (window == 0)
+    {
+        SDL_LogError(SDL_LOG_CATEGORY_ERROR, "Failed to create the SDL Window: %s\n", SDL_GetError());
+        SDL_Quit();
+        return EXIT_FAILURE;
+    }
+    SDL_GLContext gl_context = SDL_GL_CreateContext(window);
+    SDL_GL_SetSwapInterval(1); // Enable vsync
+
+    // Query OpenGL device information
+    const GLubyte* renderer = glGetString(GL_RENDERER);
+    const GLubyte* vendor = glGetString(GL_VENDOR);
+    const GLubyte* version = glGetString(GL_VERSION);
+    const GLubyte* glslVersion = glGetString(GL_SHADING_LANGUAGE_VERSION);
+    const char * new_line = "\n-------------------------------------------------------------\n";
+    SDL_LogDebug(SDL_LOG_CATEGORY_APPLICATION, "%s%s%s%s%s%s%s%s%s%s",
+        new_line,
+        "GL Vendor : ", vendor,
+        "\nGL GLRenderer : ", renderer,
+        "\nGL Version : ",  version,
+        "\nGLSL Version : ", glslVersion,
+        new_line);
+
+    // Setup Dear ImGui context
+    IMGUI_CHECKVERSION();
+    ImGui::CreateContext();
+    ImGuiIO& io = ImGui::GetIO();
+    // Android issue: NoMouseCursorChange config prevents SDL_SetCursor call
+    // in imgui_impl_sdl.cpp; SDL_SetCursor causes invalid operation error spam
+    io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange | ImGuiConfigFlags_NavEnableKeyboard;
+    io.WantSaveIniSettings = false;
+    // Setup Platform/Renderer bindings
+    ImGui_ImplSDL3_InitForOpenGL(window, gl_context);
+    ImGui_ImplOpenGL3_Init();
+
+    // Setup Style
+    ImGui::StyleColorsDark();
+    //ImGui::StyleColorsClassic();
+
+    bool show_demo_window = true;
+    bool show_another_window = false;
+    ImVec4 clear_color = ImVec4(0.45f, 0.55f, 0.60f, 1.00f);
+
+    // This is necessary to reposition the demo window
+    ImGui_ImplOpenGL3_NewFrame();
+    ImGui_ImplSDL3_NewFrame();
+    ImGui::NewFrame();
+    ImGui::SetNextWindowSize(ImVec2(io.DisplaySize.x * 0.80, io.DisplaySize.y * 0.45), ImGuiCond_FirstUseEver);
+    ImGui::SetNextWindowPos(ImVec2(io.DisplaySize.x * 0.05, io.DisplaySize.y * 0.30), ImGuiCond_FirstUseEver);
+    ImGui::Begin("ImGui Demo");
+    ImGui::End();
+    ImGui::EndFrame();
+
+    // Main loop
+    bool done = false;
+    while (!done)
+    {
+        // 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.
+        // - When io.WantCaptureKeyboard is true, do not dispatch keyboard input data to your main application.
+        // 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_ImplSDL3_ProcessEvent(&event);
+
+            if (event.type == SDL_EVENT_QUIT)
+                done = true;
+        }
+
+        // Start the Dear ImGui frame
+        ImGui_ImplOpenGL3_NewFrame();
+        ImGui_ImplSDL3_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::SetNextWindowPos(ImVec2(io.DisplaySize.x * 0.05, io.DisplaySize.y * 0.05), ImGuiCond_Once);
+
+            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::SetNextWindowSize(ImVec2(200, 100), ImGuiCond_FirstUseEver);
+            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();
+        }
+
+        glViewport(0, 0, (int) io.DisplaySize.x, (int) io.DisplaySize.y);
+        glClearColor(clear_color.x, clear_color.y, clear_color.z, clear_color.w);
+        glClear(GL_COLOR_BUFFER_BIT);
+
+        // Rendering
+        ImGui::Render();
+
+        //glUseProgram(0); // You may want this if using this code in an OpenGL 3+ context where shaders may be bound
+        ImGui_ImplOpenGL3_RenderDrawData(ImGui::GetDrawData());
+        SDL_GL_SwapWindow(window);
+    }
+
+    // Cleanup
+    ImGui_ImplOpenGL3_Shutdown();
+    ImGui_ImplSDL3_Shutdown();
+    ImGui::DestroyContext();
+
+    SDL_GL_DeleteContext(gl_context);
+    SDL_DestroyWindow(window);
+    SDL_Quit();
+
+    return EXIT_SUCCESS;
+} // main

examples/example_android_sdl3_opengl3/README.md

@@ -0,0 +1,9 @@
+# Dear ImGui Android Example
+
+This example runs the Dear ImGui demo app on modern Android (targeting API 33+). The `setup.sh` looks for a SDL3 submodule and then tries to run an `androidbuild.sh` script from within the SDL3 submodule.
+
+Set JAVA_HOME, ANDROID_HOME, and ANDROID_NDK_HOME environment variables in order to run `setup.sh`.
+
+After running `setup.sh` there is a generated Android Activity and Gradle files in the SDL3 submodule under the `SDL/build/` directory.
+
+Example Gradle build: `ANDROID_HOME=MY_SDK_PATH ANDROID_NDK_HOME=MY_NDK_PATH ./gradlew installDebug`. This should install the demo app on a connected emulator or physical device.

examples/example_android_sdl3_opengl3/SDL

@@ -0,0 +1 @@
+Subproject commit 0d7df16812c75c4a587d7d2673e3d1a5f2c2879b

examples/example_android_sdl3_opengl3/setup.sh

@@ -0,0 +1,17 @@
+#!/bin/bash
+
+JAVA_PKG_NAME="com.example.imgui"
+
+SDL_DIR="SDL"
+SDL_BUILD_SCRIPTS_DIR="${SDL_DIR}/build-scripts"
+
+if [ ! -d "${SDL_DIR}" ]; then
+    echo "Cloning submodules..."
+    git submodule update --init --recursive
+fi
+
+ANDROID_JNI_PATH="${SDL_DIR}/build/${JAVA_PKG_NAME}/app/jni/src"
+
+if [ ! -d "${ANDROID_JNI_PATH}" ]; then
+    bash ${SDL_BUILD_SCRIPTS_DIR}/androidbuild.sh $JAVA_PKG_NAME < ../../imgui.cpp ../../imgui.h ../../imconfig.h ../../imstb_rectpack.h ../../imstb_textedit.h ../../imstb_truetype.h  ../../imgui_internal.h imconfig.h ../../imgui_widgets.cpp ../../imgui_tables.cpp ../../imgui_draw.cpp ../../imgui_demo.cpp ../../backends/imgui_impl_opengl3.cpp ../../backends/imgui_impl_opengl3.h ../../backends/imgui_impl_sdl3.cpp ../../backends/imgui_impl_sdl3.h DearImGuiDemo.cpp
+fi