Odin UI

Odin UI is a reusable immediate-mode UI package distributed as a self-contained folder. Copy the complete UI/ directory into an Odin project and import it locally:

package main

import ui "./UI"

main :: proc() {
	app := ui.ui_begin_app()
	if app == nil do return
	defer ui.app_destroy(app)

	for !app.quit {
		ui.app_begin_frame(app)
		ui.text(app, "Hello from Odin UI")
		ui.app_end_frame(app)
	}
}

Application resources

Keep application assets outside the library. By default, paths passed to image_path, video, and font styles are relative to the application's assets/ directory. On desktop, that directory is resolved beside the executable, not relative to the current working directory. For example:

ui.image_path(app, "images/logo.png")
ui.text(app, "Custom font", user_style = {font_name = "fonts/body.ttf"})

The directory can be changed per application:

app := ui.ui_begin_app(asset_dir = "resources")

The same asset_dir is used on Android. The Android packaging task copies the application's asset directory into the matching packaged asset path; set APP_ASSET_DIR when building if it differs from assets.

Odin UI embeds its Caacupe One default font and built-in component icons in the package. They need no runtime files and are not copied into the application's asset directory.

Desktop build

The package includes its Odin SDL2/SDL2_net bindings and SDL2, SDL2_image, SDL2_ttf, SDL2_net, and FreeType source dependencies. Build those native dependencies locally inside the copied library folder:

make -C UI desktop-libs

Build and launch the included desktop smoke app with:

make -C UI desktop-run

For consumer applications, locally built shared libraries are under UI/build/desktop/. The Odin SDL2_net binding imports system:SDL2_net, so consumers that use networking should add the SDL2_net build output to their linker search path and runtime library path, and import the bundled binding:

odin build . -extra-linker-flags:'-LUI/build/desktop/sdl2-install/lib -LUI/build/desktop/sdl2-image -LUI/build/desktop/sdl2-ttf -LUI/build/desktop/sdl2-net -Wl,-rpath,$ORIGIN/UI/build/desktop/sdl2-install/lib:$ORIGIN/UI/build/desktop/sdl2-image:$ORIGIN/UI/build/desktop/sdl2-ttf:$ORIGIN/UI/build/desktop/sdl2-net'

import net "./UI/vendor/sdl2/net"

The compiler's Odin standard library is still required, but no Odin collection or global library configuration is needed. Video playback uses FFmpeg; the Android build uses the bundled Android arm64 prebuilt. Desktop applications that use video must provide compatible FFmpeg libraries at link/runtime.

Run the library tests from the library directory with:

odin test .

Android build

The Android project under android/ is a build host for an application that imports this package. It uses the consuming app's Odin source directory and asset directory, while keeping the SDL/FFmpeg native build and Gradle project inside UI/.

For the included Android smoke-test app:

make -C UI android-apk

For a project laid out as MyProject/main.odin, MyProject/assets/, and MyProject/UI/:

make -C UI android-apk APP_ROOT=.. APP_ASSETS_DIR=../assets

The consumer's Android entry source must export odin_app_start for SDL's native activity to invoke its main procedure. APP_ASSET_DIR defaults to assets; override it when the app uses a different virtual asset path. Declare Android permissions in a permissions file in APP_ROOT, one name per line; blank lines and # comments are ignored. For example:

INTERNET
ACCESS_NETWORK_STATE

The included Android smoke app declares its required permissions in tests/android/permissions. To start a project configuration from the available Android SDK 34 permissions, copy tests/android/permissions.template to your project's permissions file and uncomment only the permissions your app needs.

The Android build validates the entries and regenerates the manifest whenever the file changes. See android/README.md for details. Android builds require the Android SDK/NDK and a supported JDK; see android/README.md.

Licensing

Third-party license notices are retained beside the bundled dependencies, including SDL2_net 2.2.0 under third_party/SDL2_net-2.2.0/LICENSE.txt. The repository does not currently specify a license for Odin UI's original code; choose and add one before redistributing the library.