原作者：Luca Fiorentini, Giovanni Lo Re
Giovanni Lo Re
Introduction – Hi all! It’s a pleasure for me to give you an overall view of this project! This image started last summer… Due to vacation I decided to take a model from our short in development and use it to study lighting and shading with a cartoony look.
简介 —— 大家好！我很高兴给大家做一个大体的介绍。这张图是从去年夏天开始…由于休假，我决定用有限的时间给自己做一个提升，并用它来研究灯光和卡通材质。
I wanted to create an ambient with an alien look… The principal character is from another world (the one with the big foot outdoor) and I wanted to communicate that with little details here and there. As usual I asked Giovanni Lo Re (a really good friend I used to work within Italy) to make a little sketch of the scene and to design the objects.
我想用局外人的眼光来创建一个场景…主要特点是从另一个世界（就是在门外的一双大脚），我想在这里于一些细节进行沟通。像往常一样，我请Giovanni Lo Re（一个很好的朋友，我曾经工作在意大利），对场景做一个速写和设计物体。
After collecting some reference images (especially from other 3d artists) and after some emails he ended up with this drawing and was a really good starting point! Then he sent me some detailed drawings of the tools and the car.
Modeling – Modeling was pretty straightforward… All poly modeling and a lot of little pieces! For the car, after the body was finished, I started modeling the interior and the details.
As to the environment, I modeled every object separately and then imported them as references. I wanted to find a good camera angle, similar to the one of the drawing. At the end I decided to turn wall on the right side about 45 degrees to have more space and get a nicer shot.
Texturing and Shading – For texturing I’ve been using the Total Texture collection. For the wall I took the base layer from the Total Texture 1, some dirt from Total Texture 5 and 2 and mixed them in Photoshop following the UV layout… same for the tires.
纹理和贴图 —— 对于材质我一直在使用3D Total的素材库。对于墙我从素材库1中得到底色，从5和2素材库中找到一些污迹。然后在UV输出后在PS中把它们进行混合..对轮胎进行一样的操作。
For the sky Giovanni started from a base from the Total Texture 15 and continued adding details, painting clouds and little planets.
For the carPaint and tires material I decided to go with layered materials… this gave me the ability to add dirt, scratch and all the little details I wanted with the minimum effort. The texturing is based mostly with Total Texture 5 & 8 because they’re full of dirt masks… after importing them in Photoshop I reduced the details to make them cartoonier.
and I make a lot of masks to control the layering. The shaders are quite simple, lots of fresnel effect for glass and metal and then simple shader trees layered with a mib_color_mix node.
Lighting and Rendering – At the beginning I wanted to try the new Mental Ray pass system, but after a while I liked the raw render from Maya so I decided just to use beauty pass, occlusion pass, one pass for light fog and some masks. I ended with 16 passes, mostly masks because I wanted to do separate color correction while still doing an image ready for animation without hand drawn masks or retouching in Photoshop.
灯光和渲染 —— 在开始的时候我想尝试Mental Ray新的渲染系统，但经过一段时间，我还是喜欢从玛雅渲染出原始的图。所以我决定只用beauty层，OCC层，一些灯光雾和一些遮罩。我总共分了16 层，大部分都是遮罩层。因为我想要做独立色彩校正，同时在出图的时候不用手画遮罩或者在PS里润色。
Lighting was real fun and also time consuming… I think I’ve spent most of the time on this and on compositing. I rendered a lot of different versions with different colors and light rigs going back and forth between versions until we found a good combination of mood and details.
I used a technique I saw in a DVD from Jeremy Vickery (www.jermilex.com) on the use of Ambient Occlusion to simulate bounce/fill lighting: all you have to do is to connect the output of the AO to the ambient color of ALL the shaders in the scene. You have to think about it like this: the light color is going to light the non occluded parts, while the dark one is going to light the occluded ones… so, avoid pure black and pure white!!! I put some orangish tones to warming the image up.
After establishing the key + fill I started adding bounce lights for the sunLight and a lot of rim light to separate the objects from the background. This is a screenshot of the scene and a list of all the lights in the scene. I also added some reflectors with a white surface shader to give that cartoony look to the reflections on the glasses.
Compositing – This was the first time I tried to use Nuke and I really learnt a lot!
I rendered some passes as 32bit floating point openEXR (beauty, zDepth) to have more freedom and the rest as 8bit iff.
Nuke gives you the possibility to create new channels from images, so I used the colorID passes to put new channels into the pipe in order to select the various objects with just one click through the whole script. This was especially useful while doing color correction. Height passes and the light fog helped me to improve the atmosphere while the vignetting allowed me to concentrate the attention on the car, which was supposed to be the most important spot of the image. Here you can see a screenshot of the whole script with some explanations!
Nuke可以让你从图片中创建新的通道，所以我用了colorID层来把主要的物体出场景中勾勒出来。 当在色彩校正的时候是非常有用的。高光层和灯光雾让场景变的更有气氛，而光晕让我把注意力集中在汽车，这应该是图像中最重要的关注点。在这里你可以看到一 个带解释的全景的屏幕截图！
Conclusion – I’m really happy about writing this tutorial and sharing what I’ve learnt with you! I think that this has been a little like a production workflow because we had to get feedback from each other by mail… sending progresses and trying to understand each other just by reading. Maybe if we had been able to work side by side we wouldn’t have done all those tests, but I think that this has been a nice research and I’m just looking forward to start a new project If you have any questions feel free to write me! Thank you to everyone!
结尾 —— 我真的很高兴能写这篇教程，并与大家分享我所学到的东西！我觉得这已经像一个小的生产流程，因为我们不得不通过邮件来反馈信息…并试图通过阅读来理解 对方的意图。也许如果我们能够并肩努力，我们就不用做这些测试了，但我认为这是一个很好的研究和我只是期待着开始一个新项目：）如果您有任何问题随意写信 给我！谢谢大家！