Game engine · In development

Bring worldsto light.

A GPU-driven renderer, a live editor, and an agent that works in your project.

See the renderer Engine overview

Hikari / Visual studyScroll

Runs natively on

Apple Silicon Metal 4Windows Direct3D 12

Runtime

Native code, written in Zig

Explicit memory ownership and a dedicated render thread.

Graphics

GPU-driven geometry

Compute culls meshlets and writes the draw arguments, on Metal 4 and Direct3D 12 alike.

Iteration

Recompile without restarting

Edit scenes, test in Play, and rebuild game code while the editor stays open.

01 / Rendering

The GPU decides what gets drawn

Bindless resources, meshlet culling, ray tracing, screen-space effects, and froxel volumetrics, all reading the same scene data.

Hikari viewport capture of the Bistro exterior at golden hour, with low sun on the facades, string lights over the street, and a blue scooter. — Bistro / Golden hour
Main asset: Amazon Lumberyard Bistro by Amazon Lumberyard · via NVIDIA ORCA · CC BY 4.0

Bindless resources: Geometry, materials, and textures live in GPU tables. Shared resource indices replace per-material texture rebinding.
GPU-driven submission: Compute builds the visible geometry streams and indirect draw arguments. The GPU drives scene-mesh submission.
Meshlet culling: Meshlets bring frustum, backface-cone, and two-phase Hi-Z culling to the GPU. Shadows use the same geometry-pulling architecture.
Ray tracing: Ray-traced shadows, ambient occlusion, reflections, and global illumination share the renderer’s material and geometry data.
Screen-space effects: SSAO, SSGI, and hierarchical screen-space reflections add contact, bounce light, and surface detail, with configurable quality budgets.
Froxel volumetrics: Froxel volumetrics integrate light through fog and bounded media. Shape shafts, local smoke, and atmosphere with volume materials.

Debug views

Meshlets

Colour-coded geometry reveals the clusters the GPU works with.

Hikari meshlet debug view showing the Sponza courtyard geometry as individually colored clusters. — Sponza / Meshlet visualization
Main asset: Sponza Atrium by Frank Meinl / Crytek · License: source unverified

Render buffers

Inspect surface colour, normals, depth, and the layers behind the final image.

Hikari nine-panel render debug view exposing surface color, normals, depth, and other renderer buffers. — Sponza / Render-buffer debug grid
Main asset: Sponza Atrium by Frank Meinl / Crytek · License: source unverified

One shared rendering architecture. Native Metal 4 and Direct3D 12 backends.

Renderer overview

Stylized worlds

Stylized scenes, same renderer

Saturated colour, warm light, and soft haze. A stylized Japanese street, rendered by the same pipeline as the Bistro captures.

Stylized scene rendered in Hikari · EXR capture converted to SDR WebP.

Main asset: Stylized Little Japanese Town Street by Michał Solarek · CC Attribution

Light & atmosphere

Light that fills the air

Froxel volumetrics scatter light through fog and haze, and shadows carry into the volume.

Volumetric lighting study · In-engine EXR capture, converted to SDR WebP.

Main asset: Abandoned Warehouse - Interior Scene by Aurélien Martel · CC Attribution

Froxel grid

A camera-aligned froxel grid integrates light through fog and local volumes.

Shadowed scattering

Scene lights and shadow maps shape scattering, shafts, and depth.

Authored volumes

Combine global fog with bounded volumes and graph-authored volume materials.

HDR display output

HDR output that follows the display

A linear-light pipeline from scene to screen. Hikari adapts HDR output to the display, keeping bright highlights expressive and everyday UI comfortable.

Apple EDRWindows scRGBHDR10 / PQ

A dark spaceship corridor with metallic wall panels, glowing red lights and bright highlights diffused through haze. — Spaceship corridor · HDR lighting rendered in Hikari. Tone-mapped SDR preview of the EXR capture.
Main asset: Spaceship Corridor by the_table · CC Attribution

Peak-aware tone mapping: Display-aware tone mapping and BT.2390 roll-off fit highlights to the screen’s current peak brightness.
Paper-white reference: UI and diffuse white share a configurable brightness reference, independent of HDR highlights.
Automatic HDR and SDR: Detects OS-enabled HDR, falls back to SDR, and switches live without restarting the engine.

HDR pipeline

02 / Editor

Edit, play, and recompile in one session

Scene authoring and the live runtime share one editor. Scene, asset, and code changes arrive without a restart.

Editor workflow

Build the scene
Arrange actors, tune components, and work with prefabs. Undo and redo keep your edits reversible.
Play in a separate world
Run the game in a separate Play world. Stop returns you to your authored scene.
Recompile in place
Rebuild game logic in Edit mode while the scene stays open. Asset watching brings changed content back into the editor.

Hikari Editor / Bistro scene

Main asset: Amazon Lumberyard Bistro by Amazon Lumberyard · via NVIDIA ORCA · CC BY 4.0

Material, animation, and particle tools · Profiling · Extensible panels · Local MCP integration

Visual authoring / Animation

Animation graphs, previewed beside the character

Connect clip states, shape transitions, and drive them with parameters. Preview your character beside the graph as you tune its movement.

Animation graphs

Locomotion graph · State transitions, footstep events, and a live skeleton preview.

Visual authoring / Materials

Material graphs with a live preview

Build materials as graphs, inspect them in the live preview, and author custom shaders in Akari for Metal, Direct3D, and Vulkan/SPIR-V.

Shader authoring

Hikari material graph editor showing texture-coordinate connections to albedo, normal, and metallic/roughness nodes, colour and luminance controls, and a live sphere preview. — Hikari / Material graph editor

UI framework

Game UI, built visually or in Zig

Build screens visually with live previews, device presets, and editable properties. Bind them to your game, or create the entire interface directly in Zig. Both use the same native UI framework.

UI framework

Hikari’s UI document editor previewing an RPG inventory, with a node outline, layout and appearance properties, and editable data slots. — UI editor · Inventory screen with live data slots and an interactive preview.

Adaptive layout

Stacks, grids, wrapping rows, and flexible sizing. Build HUDs, menus, and world-space labels with the same layout tools.

Typed data slots

Named, typed slots carry game data into the screen; widget events flow back to code. Hot reload updates the layout while keeping slot values.

Keyboard and gamepad focus

Keyboard and gamepad focus navigation, scrolling, and modals are built in. Virtual lists build only the items in view.

Themes and rich text

Themes, custom fonts, rich text, and nine-slice artwork. Add localized text and transitions, with UI scaling and reduced-motion preferences.

Writing UI in code

Use hi.ui() to compose widgets directly in Zig and handle their results immediately. The visual editor is optional.

Build your first UI

03 / AI & MCP

An MCP server inside the editor

Connect an AI agent to the running editor through the Model Context Protocol. It reads the same scene, asset, and project data you do.

Your AI agentMCPHikari Editor

MCP interface

Scenes and prefabs: Inspect actors and component schemas. Create scenes, edit prefabs, and apply coordinated changes.
Assets and graphs: Create and import assets. Author materials, animation graphs, and particle systems through structured tools.
Project settings: Work with project settings, plugins, gameplay tags, and asset import options.
Viewport and console: Position the camera, frame a subject, capture the rendered viewport, and inspect console output.

Edits follow editor rules. Agent edits use native validation, conflict checks, and undoable scene operations. Activity is recorded in the project audit log.

Enable MCP in Editor Settings and copy the connection configuration to your agent. Local access, authenticated per project.

04 / Toolchain

Six tools, one build

From source assets to a playable build, each part has one job. Kaji conducts the build.

Toolchain overview

Hikari

Zig

Native runtime, rendering, and editor.

Shinra

Rust

Asset cooking, watching, and packaging.

Akari

Rust

One shader language for Metal, Direct3D, and Vulkan/SPIR-V.

Kawa

Embedded scripting for game logic.

Tenkai3D

Odin

3D physics and character controllers.

Kaji

C# / .NET

One build flow for games and the editor.

Compose an actor from the capabilities it needs.

const hi = @import("hikari_game");

pub const BeaconEntity = hi.defineEntity(.{
    .archetype = "beacon",
    .components = .{ hi.ComponentRender, hi.ComponentLight },
});

Status

In active development

Hikari runs on macOS and Windows today. The documentation covers the systems, tools, and design behind the engine.

Read the documentation Download