作者: Gábor Miklós
翻译：purpelsun ( 翻译中有错误之处请谅解，并请帮忙指出！谢谢！)
Software Used :使用软件
As I am a great music lover and I love lots of different musical styles, I decided to create a musical instrument. At first, I didn’t know which one I was going to choose to recreate, but I liked the sound of making a guitar and so I decided to give it a go.
The first idea was to put inlays and ornaments on it. I didn’t just want to make an ordinary guitar; I wanted to create a gentle instrument.
I used several different ways to model the various parts of the guitar, with the main two being box modeling and patch modeling. Patch modeling is a very good way to make curved surfaces, like the body of the guitar or guitar neck, because it gives you an accurately curved mesh.
我使用不同的方法来创建吉他的不同部位，最主要用到的技法是box modeling 和patch modeling。Patch modeling是创建曲面的非常好的方法。比如吉他的面板和neck,，因为它会让你创建精确的曲面。
The whole mesh was MeshSmooth capable and it was about 128,532 polygons and 94,000 vertices (what a nice, round number!) Of course these figures are for the model without any MS on it. For those renders you have to kick up the MeshSmooth and the poly count jumps to about 300,000.
Here are a few screenshots from the wireframe of the guitar (Fig.01 – Fig.10).
The Wooden Material:木纹材质
I used only procedural maps for the wood material. Wood is a special material; every millimeter inside and out looks different. The look of a piece of wood depends on where you cut it and this basically determines the look of the whole material.
There are two ways to create the wooden material for a guitar’s neck (or for anything else really). The first way is to flatten the UV Map and texture it with real wood textures, but on a curved shape like the guitar neck, it’s not very easy to do this, or very accurate.
The second method is to use procedural maps, which is much easier and means you don’t have to flatten the UVs. It will also spare the system memory while rendering, it has nearly unlimited resolution so it won’t be pixilated in greater resolutions and it looks good too! Oh and have I forgotten to mention that it’s more accurate than simple textures and spares a lot of time? So it has a lot of advantages and I bet you can guess which method I used!
There were three parts to the wooden material I used (Fig.11):
• The main annual rings (darker and lighter)
• Splinters inside the wood that are in-line with the annual rings
• A few speckles that make the wooden material a little bit more inhomogeneous
A few corrections were needed to get a correct result. The first thing was to set the direction of the annual rings and the splinters. To do that I tried to guess how the annual rings and splinters became parallel. Fig.12 and Fig.13 show the coordinates of the splinters, and Fig.14 shows the coordinates of the wood map. With these settings the two types of maps were parallel and they were also in-line with the Z-axis of the object.
If you want to know more about how this material works then you can download it by clicking here.
Okay, here are the specific textures I used for this image. I used CorelDRAW to make them (Fig.15).
The strings have an over-tiled Gradient Ramp texture on them and it’s fully procedural of course (Fig.16).
First I wanted to create a scene, but I changed my mind after I’d finished the guitar. Since I wanted to show you every part of it, I didn’t feel necessary to create an entire scene. Alright, but what could I do instead? Should I create an ordinary blue-orange studio scene? No, it was too boring. Should I use HDRI? No, never, I hate it – it doesn’t give accurate results as it hasn’t got distance from the objects. How about using original lights? Maybe … but how?
After a little thinking, I Googled for some real studio lighting pictures. I was lucky and found quite a few. I then created two new types of light sources for myself. (I just wanted to prevent the hard edges on the reflections generated by simple VRayLights) (Fig.17).
小想一会儿后。我在Google上搜索了一些真实的studio lighting图片。我很幸运找到了不少类似的图片。然后我就创造了两种新的类型的光源。(我只是想防止VRayLights产生反射的硬边。) (Fig.17).
Here are a few things about lighting that I’d just like to mention at this point:
• For diffuse light it is better to use a desaturated light blue color, and for directional it is better to use a yellow one.
• Turn off the “Affect reflection” and “Affect specular” buttons.
• The directional light needs to look at the object you wish to light, and needs to be double-sided. The diffuse needs to be looking at the hemisphere and the double-sided option should be off… (You can, of course, use caustics with type 1 lights too. It depends on which is better for your scene).
• The most important thing of all is to exclude all other objects on the Diffuse light option except the light hemisphere (Don’t exclude if using Type 2 light)
The next thing now was to put the lights in the correct places in my image. The lights that I wanted to see from the reflections were diffuse lights (I tried to find a place and size where I could see them from the reflections). The directional light was a good choice to generate nice, smooth shadows and caustics. I put them beside the model, or more then 45 degrees from perpendicular, and it gave a very nice result, as you can see in Fig.18.
I want to point out one thing at this point: to get a realistic look for reflections it’s a good idea to use 5-10 light sources and try to cover more than 50-60% of the places where there is no light. With this method there will only be a few percent of dark places on the reflections, which is just as much as it really needs.
You can also use other shapes to make a nice, realistic reflection. If you changed to a flat shape then you can easily simulate a wall or something else … you can make a plane and light it from the bottom edge or you could put two or more lights aside so that it looks like a window from the reflections.
Here is the lighting combination that I used for my rendered scene (Fig.19).
post Processing 后期处理:
I used HDRI to save the raw renders. It’s the best format to save your images in because it has 32bits/channel information from your renders. Of course it gives you a little bit of an interesting result when you load it into Photoshop, but that’s quite easy to prevent. Sadly Photoshop can’t make any procedures with this format so you have to change the color depth to 16bits/channel. With this method you still have 65536 colors/channel so you get very, very good gradients.
我使用 HDRI来保存原始的渲染。这是保存图片的最好的格式，因为他包含了从你渲染得到的每通道32位色的信息。当然，当你在Photoshop中导入它是也会有趣的多。遗憾的是Photoshop不能操作这类型的图片，所以你不得不改变图片的色深为美通道16色。使用这种方法，你仍然可以得到没通道65536 种颜色，非常丰富的色彩了。
The next step was to correct the colors and make the picture natural. I used exposure and Blending methods to accomplish this, mostly Multiply, Overlay and Scene. I rendered down the ZDepth pass in 3ds Max and then I used Lens Blur to make DOF. I put Chromatic Aberration on to the picture with great care – you just have to feel it and not see it. I also put a very fine glow on to the highlighted places and some color correction.
下一步就是调整颜色使得图片看起来更加自然，我使用exposure 和Blending的方法来实现它。大部分使用Multiply, Overlay 和Scene。我在3ds Max中渲染出Z通道，然后是镜头模糊来创建景深效果。我对图像小心的校色，你必须去感觉它而不是看他。我也在高亮的地方放置了一些辉光并调色。
That’s all you have to know about this picture! I hope you enjoyed this Making Of and found it useful (Fig.20).