本视频教程是由Gnomon机构出品的森林制作技术2-Maya与mental ray中草与植物的实例化技术教程，时长：8小时41分，大小：4.96 GB，格式：MOV高清视频，附工程源文件，教程使用软件：Maya AE PSmental ray ，作者：Alex Alvarez，语言：英语。CG数据库整理。

在本DVD中，Alex讲解了如何使用MAAY,Paint Effects，还有Menral ray来创建逼真的草，同时为大家分享他制作一个完整的自然环境的技术。我们先从查看Paint Effects的基本的grass library开始，讲解了如何通过一些基本的调整来让草看起来更加自然，通过曲线与实例化来让大块的区域被草覆盖。通过使用实例化，粒子， 表面发射器，Alex告诉我们如何在一个很大的场景中布满草的几何体，并且使用最小的内存来渲染上百万的多边形。里面使用了一个基于表达式的技术，根据表面来决定被实例化的对象的方向，这是一个对植物与树来说不太重要的问题，但是对于草来说却是相当重要的。当我们需要的各个元素被交互式的，并且精确的放置了，Alex为我们讲解了如何使用一个免费的几何体绘制代码，还有如何将实例化的粒子bake到几何体上。教学深入的讲解了如何创建忒图，mia材质，还有使用物理真实的sun/sky。Alex还讲解了如何渲染与应用zDepth层来添加后期的景深与雾效，如果渲染真实的体积雾特效，还有如何在AE与PHOTOSHOP中通过使用色彩校正与像Magic Bullet, LensCare，还有Sapphire这样的插件来提升真实感。

GNOMON教程，每每给我们于激情与期待！让我们在CG设计路上不再独行！让我们共同期待！让我们共同期待与业界CG顶尖设计师的面对面！少玩多花些时间多学习学习，让我们的商业作品与众不同！Gnomon的教程向来以其前沿的技术和清晰的视频质量而受到广大用户的青睐。

Maya 是目前世界上最为优秀的三维动画的制作软件之一，主要是为了影视应用而研发的，所以在出世后不久就在《精灵鼠小弟》、《恐龙》等这些大片中一展身手。除了影视方面的应用外Maya在三维动画制作，影视广告设计，多媒体制作甚至游戏制作领域都有很出色的表现。初识Maya 是目前世界上最为优秀的三维动画的制作软件之一，它是Alias|Wavefront公司在CG数据库1998年才推出的三维制作软件。虽然相对于其他老牌三维制作软件来说Maya还是一个新生儿，但Maya凭借其强大的功能，友好的用户界面和丰富的视觉效果，一经推出就引起了动画和影视界的广泛关注，成为顶级的三维动画制作软件。

The Gnomon Workshop Forest Techniques Part 2 Grass and Plant Instancing in Maya Mental Ray

In this DVD, Alex covers how to create realistic grass using Maya, Paint Effects and Mental Ray while also sharing his techniques for developing a complete natural environment. We begin by evaluating the default Paint Effects grass library with discussion on the basic adjustments needed to make grass more natural. Techniques for covering large areas with grass are then explored via curves and instancing. Through the use of instancing, particles and surface emitters, Alex shows how to populate large scenes with grass geometry, rendering millions of polygons with a minimal RAM footprint. Included is an expression based technique for orienting instanced geometry with the normal of the generating surface, an issue less important for plants or trees but often very important for grass. When elements need to be interactively and precisely placed, Alex also demonstrates the use of a freely available geometry paint script, as well as how to bake particle instances to geometry. Generating textures, miaMaterials and workflow in conjunction with Physical Sun/Sky is thoroughly discussed. Alex also demonstrates how to render and utilize zDepth passes to add post depth-of-field and fog effects, how to render true volumetric fog effects, as well as Photoshop and After Effects post techniques to increase realism through the use of color correction and plug-ins, including Magic Bullet, LensCare and Sapphire.

关于作者：Alex Alvarez

Founder, Director The Gnomon Workshop

Gnomon School of Visual Effects

Alex Alvarez is the founder and president of the Gnomon School of Visual Effects in Hollywood, the Gnomon Workshop, Gnomon Gallery, SketchTheatre and Gnomon Studios. Having dedicated the past fifteen years to educating students and professionals around the world, Alex has helped change the face of computer graphics and design education. He has been published in industry magazines, websites and books, plus he has taught workshops at several major trade conferences. He continues to work on personal and professional projects, recently as a creature development artist on Avatar, Star Trek, Green Lantern and Prometheus. Prior to Gnomon, Alex worked for Alias|Wavefront as a consultant and trainer for studios in the Los Angeles area. Alex is an alumnus of the Art Center College of Design and the University of Pennsylvania.