Metallic vs Specular Workflow 金属与高光工作流 Standard Shader系列3

Metallic vs Specular Workflow 金属与高光工作流

本文档主要是对Unity官方手册的个人理解与总结（其实以翻译记录为主：>）
仅作为个人学习使用，不得作为商业用途，欢迎转载，并请注明出处。
文章中涉及到的操作都是基于Unity2018.3版本
参考链接：https://docs.unity3d.com/Manual/StandardShaderMetallicVsSpecular.html

Two workflows

When creating a material using the Standard shader you will have the choice of using one of two flavours, “Standard” and “Standard (Specular setup)”. They differ in the data they take as follows:
当使用标准着色器创建材质时，你可以选择使用两种风格中的一种，“标准”和“标准(高光设置)”。它们所取数据的不同如下:

Standard: The shader exposes a “metallic” value that states whether the material is metallic or not. In the case of a metallic material, the Albedo color will control the color of your specular reflection and most light will be reflected as specular reflections. Non metallic materials will have specular reflections that are the same color as the incoming light and will barely reflect when looking at the surface face-on.
标准:着色器暴露一个“金属”值，说明材质是否是金属的。在金属材料的情况下，反照率颜色将控制你的高光反射的颜色，大多数光将被反射为高光反射。非金属材料将具有与入射光相同颜色的高光反射，并且在正面观察表面时几乎不会反射。

Standard (Specular setup): Choose this shader for the classic approach. A Specular color is used to control the color and strength of specular reflections in the material. This makes it possible to have a specular reflection of a different color than the diffuse reflection for instance.
标准(高光设置):为经典的方法选择这个着色器。高光色用于控制材质中高光反射的颜色和强度。这使得高光反射的颜色与漫反射不同成为可能。

It is generally possible to achieve a good representation of most common material types using either method, so for the most part choosing one or the other is a matter of personal preference to suit your art workflow. For instance, to below is an example of a rubbery plastic material created in both Standard and Standard Specular workflows:
通常情况下，使用任何一种方法都可以很好地表示最常见的材质类型，因此，在很大程度上，选择一种或另一种是您个人的偏好，以适应您的美术工作流程。例如，下面是在标准和标准高光工作流程中创建的橡胶似的塑料材质的一个例子:

The fresnel effect visible at grazing angles in relation to the viewer is increasingly apparent as the surface of a material becomes smoother
当材质表面变得更加光滑时，相对于观察者而言，在掠入角可见的菲涅耳效应变得越来越明显

The first image represents the metallic workflow, where we are setting this material to zero (non metallic). The second setup is nearly identical but we set the specular to nearly black (so we don’t get metallic mirror-like reflections)
第一个图像表示金属工作流，我们将该材料设置为零(非金属)。第二个设置几乎相同，但我们将高光设置为近黑色(这样就不会得到类似高光的金属反射)

One might ask where do these values come from, what is “nearly black” and what makes grass different from aluminium exactly? In the world of Physically Based Shading we can use references from known real-world materials. Some of those references we have compiled into a handy set of charts you can use to create your materials.
有人可能会问，这些值从何而来，什么是“近乎黑色”，是什么让草与铝完全不同?在基于物理渲染的材质世界中，我们可以使用来自已知真实材质参考。我们已经将其中一些参考资料汇编成一组方便的图表，您可以使用它们来创建您的材质。