(一)引擎评估: 开篇闲谈

因工作需要，特对网上一些收费及免费的引擎进行评估。在搜遍整个devmaster.net及各大开发网站以后，收集了几套符合我们当前项目需求的引擎：lithtech, ogre, Nebula, nel.

1.Lithtech:

作者: Touchdown Entertainment, Inc.

授权费:10000$

 是否带有源代码: 有

图形API: DirectX8.0

语言: C++

是否带有文档: 有

个人观点:

        开发时已不需要再考虑底层的东西，观注游戏逻辑就OK.用来开发MMORPG,需要对其网络部分，及部份框架进行改造，加上其对室外地形的支持不是很好，需要自己改装其内部场景管理部分。周边工具齐全，场景编辑器，模型编辑器，特效编辑器等等一应具全。国际上很多公司都在使用，国内也有部份公司使用了他，比较出名的成品就是A3。

技术细节: (拷贝至devmaster.net)

Object-Oriented Design, Save/Load System: Scripting•The Command Editor is a powerful management tool that lets developers efficiently create spectacular cinematic effects and events with DEdit. By using commands, level designers can set key frames, start specific cinematic events, and more accurately place and time events within the context of the game. In addition, this tool allows the designer to control camera locations, script character movements, and trigger a variety of visual effects as the player’s character interacts with the game’s environment.•Includes a convenient in-game debugging tool that delivers immediate access to data for AI paths, nodes, attributes and game states, which empowers levels designers to independently debug a variety of game systems.Built-in Editors•DEdit allows level designers to create dynamic 3D environments, worlds, and levels through one easy-to-use tool, including all structures, lighting, and textures. The level designer uses DEdit to populate the world with objects and interactive items. DEdit also includes a convenient real-time lighting preview feature.•RenderStyles are custom pixel and vertex shaders that are developed within game code and leverage specific platform capabilities. These effects range from cartoon shaders to bump mapping. The RenderStyles editor features a GUI that is used to design and view custom effects in real time.•ModelEdit ensures models will be optimized to interact correctly with environments and other objects. Artists can also use ModelEdit to define specific properties, assign texture IDs, attach objects to models and manipulate animation data.•FxEd is used to create and modify visual effects. The tool enables the creation of in-game visual effects without requiring a recompile, thereby increasing the efficiency of the design and implementation of special effects.PhysicsBasic Physics, Collision Detection, Rigid Body: LightingPer-vertex, Per-pixel, Lightmapping, Gloss maps, Anisotropic: ShadowsShadow Mapping, Projected planar: TexturingBasic, Multi-texturing, Bumpmapping, Mipmapping, Projected: ShadersVertex, Pixel: Scene ManagementGeneral, Portals, Occlusion Culling, LOD: AnimationKeyframe Animation, Skeletal Animation, Facial Animation, Animation Blending: MeshesMesh Loading, Skinning, Progressive: Special EffectsEnvironment Mapping, Lens Flares, Billboarding, Particle System, Sky, Water, Fire, Explosion, Decals, Fog, Weather: TerrainRendering: Networking SystemClient-Server, Peer-to-Peer, Master Server: Sound & Video2D Sound, 3D Sound: Artificial IntelligencePathfinding, Decision Making, Finite State Machines, Scripted: RenderingFixed-function, Render-to-Texture:

2.Ogre

作者: Steve Streeting

授权费: 无，LGPL协议

图形API: OpenGL, DirectX

文档: 有

个人观点: 一个不错的图形引擎，自己对它再进行2次封装，配上自己的网络引擎，脚本引擎，声音等等，实现一个傻瓜型的引擎并不难。缺点就是，周边工具不全，需自己写场景编辑器等，还需绑定相应的物理引擎，其工作量不会很小，不是很推崇。

技术细节: (拷贝至devmaster.net)

General FeaturesObject-Oriented Design, Plug-in Architecture, Save/Load System: Scripting•Scripted material language allows you to maintain material assets outside of your code•Scriptable multipass renderingPhysicsBasic Physics, Collision Detection, Rigid Body: LightingPer-vertex, Per-pixel, Lightmapping: ShadowsShadow Mapping, Shadow Volume: TexturingBasic, Multi-texturing, Bumpmapping, Mipmapping, Volumetric, Projected: ShadersVertex, Pixel, High Level: Scene ManagementGeneral, BSP, Octrees, Occlusion Culling, LOD: AnimationInverse Kinematics, Skeletal Animation, Animation Blending: MeshesMesh Loading, Skinning, Progressive: Surfaces & CurvesSplines: Special EffectsEnvironment Mapping, Lens Flares, Billboarding, Particle System, Motion Blur, Sky, Water, Fog: RenderingFixed-function, Render-to-Texture, Fonts, GUI:

3. Nebula

作者: Radon Labs (http://www.radonlabs.de/)

授权费: 无

是否带有源码: 有

相关文档: 有

个人观点: nebula 是一套完整的引擎，物理、网络、 AI 、 UI 、脚本、场景、角色物理、网络、 AI 、 UI 、脚本、场景、角色一应具全，效率也很高。国内也有公司在使用它在开发游戏。但其资料并不是很多，国内交流的人也很少。你一但使用他开发，就必须接受他所有的模块。

技术细节: (拷贝至devmaster.net)

General FeaturesObject-Oriented Design, Plug-in Architecture, Save/Load System, Other: •Hierarchical Object Name Space: Nebula2 objects live in a hierarchical tree of named nodes similar to a file system hierarchy. An object name can be converted into a C++ pointer and a C++ pointer can be converted into a name at any time.•Nebula2 objects survive on disk as scripts that contain exactly the sequence of script commands that would put a default object of that class into an exact clone of the object which created the script.•Provides a full blown system for providing themeable user interfaces within the game•Provides basic support for threadingScripting•Commercial Maya tools available from Radon Labs (http://www.radonlabs.de/).•Scriptable in TCL, Lua, Python, Ruby. Other scripting languages can be added easily.PhysicsBasic Physics, Collision Detection, Rigid Body: •ODE integration is available.LightingPer-vertex, Per-pixel, Lightmapping, Gloss maps: TexturingBasic, Multi-texturing, Bumpmapping, Mipmapping, Projected: •Default image format for textures is DDSShadersVertex, Pixel, High Level: •Shader Based Graphics: Nebula2 is 'shader-centric', all render state is handled by the shaders•Shader parameters can be created and altered from the in-game console•DX9 implementation uses Direct3D Effect FilesScene ManagementGeneral, Portals, Octrees, Occlusion Culling: AnimationKeyframe Animation, Skeletal Animation, Morphing, Animation Blending: •High-performance skinned mesh renderer with multiple animation clips per state and blending between different states.•Many things can be animated: shader parameters, position, rotation, scale. The animations can be driven by time or any other variable of your choosing and you can choose from step, linear and quaternion slerp interpolation.•Supported file formats are nanim2 and nax2 (ascii and binary animation file formats)MeshesMesh Loading, Skinning: •Supports .wavefront object file (ascii), legacy n3d files (ascii), new n3d2 files (ascii), legacy nvx files (binary), new nvx2 files (binary)Surfaces & CurvesSplines, Patches: Special EffectsEnvironment Mapping, Lens Flares, Billboarding, Particle System, Sky: TerrainRendering, CLOD, Splatting: Networking SystemClient-Server, Peer-to-Peer: •A running instance of Nebula2 can be controlled, via the script server, from another process on the local machine or another remote machine (mainly used for debugging)Sound & Video2D Sound, 3D Sound, Streaming Sound: •Supports both OpenAL and DirectSound.Artificial IntelligenceScripted: RenderingFixed-function, Render-to-Texture, Fonts:

4.Nel

作者:

授权费用: 无,GPL协议

图形API: DirectX, Opengl

个人观点: 它是一个真正的3D mmorpg引擎，包含了服务端，客户端的一整套解决方案。渲染、地形、界面、AI 、物理、脚本、声音、客户端、服务器、服务器管理都有，还提供了大量的工具。个人对其推崇备至。