# Overview

**luma.gl** is split into several modules that are each responsible for a particular part of the rendering stack:

- `engine`: High-level constructs such as `Model`, `AnimationLoop` and `Geometry` that allow a developer to work without worrying about rendering pipeline details.
- `webgl`: Wrapper classes around WebGL objects such as `Program`, `Buffer`, `VertexArray` that allow a developer to manager the rendering pipeline directly but with a more convenient API.
- `gltools`: A set of helper functions for instrumenting and managing state on an WebGL context. This allows developers to program directly against the WebGL API with some helpful polyfilling and state tracking.
- `shadertools`: A system for modularizing and composing GLSL shader code.
- `debug`: Tooling to aid in debugging.

**luma.gl** also exposes a `core` module that simply re-exports key parts of the other modules. This can be helpful to just get started without worrying too much about fine-grained control of dependencies. The `core` module re-exports the following functions and classes from other modules:

|Module|Exports|
|------|-------|
|engine|AnimationLoop, Model, Transform, ProgramManager, Timeline, Geometry, ClipSpace, ConeGeometry, CubeGeometry, CylinderGeometry, IcoSphereGeometry, PlaneGeometry, SphereGeometry, TruncatedConeGeometry|
|webgl|lumaStats, FEATURES, hasFeature, hasFeatures, Buffer, Program, Framebuffer, Renderbuffer, Texture2D, TextureCube, clear, readPixelsToArray, readPixelsToBuffer, cloneTextureFrom, copyToTexture, Texture3D, TransformFeedback|
|gltools|createGLContext, instrumentGLContext, isWebGL, isWebGL2, getParameters, setParameters, withParameters, resetParameters, cssToDeviceRatio, cssToDevicePixels|
|shadertools|normalizeShaderModule, fp32, fp64, project, dirlight, picking, gouraudLighting, phongLighting, pbr|