korender

Kotlin Multiplatform 3D graphics rendering engine based on OpenGL / OpenGL ES / WebGL.

Korender uses declarative approach that seamlessly integrates 3D viewport into Compose Multiplatform UI. Same Korender code runs on all supported platforms.

Live web demo: https://zakgof.github.io/projects/korender/wasm/

Korender is BETA - APIs may change without notice.

Supported platforms

Platform	3D API
Desktop (Windows/Linux)	OpenGL 3.3
Android	OpenGL ES 3
Web	WebGL 2

Features

• Physically Based Rendering (PBR) metallic-roughness model
• Directional and point lights
• Shadows: Variance shadow mapping (VSM), percentage-closer filter (PCF)
• Texturing with normal mapping support
• Predefined shapes and custom meshes
• Wavefront .obj and .gtlf/.glb file loading (with animation support)
• Billboards (sprites)
• Batching (instancing)
• Heightfield (terrain) rendering
• Textured or shader sky
• Environment mapping
• On-screen basic GUI
• Custom shaders support
• Multi-pass rendering and screen-space shaders (filters)
• Simple effects (water, smoke, fire)
• Deferred shading pipeline

Examples showcase app

Precompiled:

• Web live demo
• JVM Desktop Windows
• Android APK

Examples source code

Run locally:

• Web: ./gradlew :examples:wasmJsBrowserDevelopmentRun
• Desktop: ./gradlew :examples:run
• Android: ./gradlew :examples:installRelease

!

Quick start

Code example

Korender {
  Frame {
    DirectionalLight(Vec3(1f, -1f, -1f))
    Renderable(
      base(
        color = ColorRGBA(0.2f, 1.0f, 0.5f + 0.5f * sin(frameInfo.time), 1.0f),
        metallicFactor = 0.4f
      ),
      mesh = sphere(2.0f),
      transform = translate(sin(frameInfo.time).y)
    )
  }
}

Quickstart application

• Check out QuickStart application available at https://github.com/zakgof/korender/tree/main/quickstart

From scratch

• Generate a new KMP application using Kotlin Multiplatform Wizard. Select Android, Desktop and WASM platforms.
• Add Korender dependency com.github.zakgof:korender:0.5.1
• Add the above code to commonMain
• Run on desktop: ./gradlew composeApp:run

Further reading

Explore the Korender Wiki