Horde 3D (open source)

[Tami]

Horde3D is a small open source 3D rendering engine. It is written in an effort to create a graphics engine that offers the stunning visual effects expected in next-generation games while at the same time being as lightweight and conceptually clean as possible. Horde3D has a simple and intuitive interface accessible from virtually any programming language and is particularly suitable for rendering large crowds of animated characters in next-generation quality.

The following features are implemented in the current release

General Features

* Powerful graphics engine designed to meet the requirements of next-generation games
* Shader driven architecture with SM 2.0 compatible hardware as a minimum requirement
* Simple and lightweight overall design with very few dependencies, avoiding complexity where possible
* Clean object-oriented C++ code
* Simple and intuitive C-style DLL interface for easy integration with virtually any programming language
* Cross-platform compatible using OpenGL as rendering API
* Suitable for Augmented Reality (AR) applications
* Integration Library for easy integration with game engines and other middleware like physics engines

Resource Features

* Robust resource management for avoiding unnecessary loading of data
* Garbage collection for handling resource dependencies
* Interface for loading data from files, streams or any type of archives
* Dynamic reloading of resources for more efficient development
* Loading of models and animations from optimized binary formats
* Loading of materials from a custom XML format
* Loading of shaders from a custom XML format including vertex and fragment shaders written in GLSL
* Loading of 2D and cubemap textures in jpg, png, tga and other common image formats

Scene Features

* Scene graph structure with hierarchical transformations and bounding volumes
* Optimized frustum culling on the scene graph using AABB trees
* Level of detail support
* Possibility to attach scene nodes to joints (e.g. for character props)
* Access to vertex data for collision detection and interoperability with physics engines

Animation Features

* Unified animation system working directly on scene graph
* Keyframe animation for joints and meshes
* Skeletal animation with up to 4 weights per vertex for articulated models
* Layered animation blending and mixing using masks and additive channels
* Inter-frame interpolation for smooth animations
* Access to joint data for dynamic animations and ragdoll physics
* Morph targets for facial animation and lip synchronization

Visual Features

* XML based customizable rendering pipeline with allocatable render targets and commands
* Postprocessing framework for effects like HDR, DOF or motion blur
* Support for forward rendering and different deferred shading techniques
* Support for almost all modern rendering techniques, including normal-mapped phong lighting and parallax mapping
* Realtime shadows based on Parallel Split Shadow Maps
* Shaders for materials and light source interaction
* Vertex shader skinning for rendering hundreds of animated characters
* Fully integrated particle systems that can cast shadows and receive other effects like motion blur
* Overlays for rendering GUI elements and font

Tool Features

* Powerful Collada Converter for importing model data and animation from many widely used modelling packages
* Calculation of tangent space basis for bump mapping
* Optimization of geometry for GPU cache