LIMEN

is the SDL3 platform and graphics integration for HashLink NMB.

SDL owns windows, displays, fullscreen state, input, cursors, clipboard, drag-and-drop, and native event delivery. OpenGL, Vulkan, Direct3D 11, and Direct3D 12 own GPU rendering only.

Important

This repository is the canonical implementation. HashLink embeds it through its LIMEN_SOURCE_DIR CMake option.

Haxe API

The public API follows the native subsystem layout:

import limen.platform.Platform;
import limen.platform.Window;
import limen.platform.event.Event;
import limen.platform.input.gamepad.Gamepad;

Platform.init();

final window = Window.create({
	title: "LIMEN",
	width: 1280,
	height: 720,
	resizable: true
});
final displays = limen.platform.display.Display.all();
final modes = limen.platform.display.Display.modes(displays[0].id);

final event = new Event();
while (Platform.pollEvent(event)) {
	// Handle the event.
}

window.destroy();
Platform.quit();

Platform types are grouped under limen.platform.event, limen.platform.cursor, limen.platform.input, limen.platform.display, and limen.platform.system.

Graphics backends own their context and device setup. For example, an OpenGL window uses Window.SDL_WINDOW_OPENGL and limen.graphics.opengl.Context.create(window). D3D12 concepts live under limen.graphics.d3d12.command, descriptor, pipeline, query, resource, and shader. Vulkan follows the equivalent package structure.

The native build produces exactly:

limen.hdll - Core of LIMEN
limen_opengl.hdll - GL driver (includes on all targets)
limen_vulkan.hdll - Vulkan driver (includes on all targets)
limen_d3d11.hdll - Direct3D 11 (includes on all windows targets)
limen_d3d12.hdll - Direct3D 12 (includes on WinX64 ONLY)

Windows build and install directories also contain the dynamically linked runtime DLLs beside the modules:

Contains and using only by Direct3D 12

dxcompiler.dll
dxil.dll

Standalone build

cmake -S . -B build \
  -DLIMEN_HASHLINK_ROOT=/path/to/hashlink-nmb \
  -DLIMEN_BUILD_OPENGL=ON \
  -DLIMEN_BUILD_VULKAN=ON \
  -DLIMEN_BUILD_D3D11=ON \
  -DLIMEN_BUILD_D3D12=ON
cmake --build build

SDL3 is built statically by CMake. Set LIMEN_SDL3_SOURCE_DIR to use a local SDL3 source tree instead of the pinned fetched release.

DLSS support is disabled by default and is not required to build or install LIMEN. On Windows x64, set LIMEN_BUILD_DLSS=ON and LIMEN_STREAMLINE_SDK_ROOT to build limen_dlss.hdll; the Streamline import library and runtime DLLs are required only for that opt-in module.

CMake locates the DXC runtime DLLs from the Vulkan SDK or HashLink's include/dx distribution. Their locations can be overridden with LIMEN_DXCOMPILER_RUNTIME_DLL and LIMEN_DXIL_RUNTIME_DLL.

Set LIMEN_BUILD_AFTERMATH=ON to add NVIDIA Nsight Aftermath GPU crash diagnostics to the D3D12 backend. Set LIMEN_AFTERMATH_SDK_ROOT to the SDK root, or define NSIGHT_AFTERMATH_SDK; CMake links the matching x64 or x86 import library and packages its runtime DLL beside limen_d3d12.hdll. The include directory, library, and runtime DLL can be overridden with LIMEN_AFTERMATH_INCLUDE_DIR, LIMEN_AFTERMATH_LIBRARY, and LIMEN_AFTERMATH_RUNTIME_DLL.

Enable LIMEN_BUILD_TESTS for the native event-translation tests.

HashLink integration

HashLink NMB pins LIMEN as the libs/limen submodule and builds it directly with CMake. To test changes without updating that pin, configure HashLink against this checkout:

cmake -S /path/to/hashlink-nmb -B /path/to/hashlink-nmb/build \
  -DLIMEN_SOURCE_DIR=/path/to/Limen

After a LIMEN revision passes CI, update HashLink's libs/limen submodule. The gitlink is the single source of truth for the pinned revision. HashLink's manual Pin LIMEN revision workflow updates it after the integration matrix succeeds.