About the unity in the PBR technology and materials unity5 default shader and traditional comparison

At first, I didn't know what PBR was (physically Based Rendering) and later discovered it was a new way of rendering.

It corresponds to the material is PBS (physically Based Shader)

There are two types of PBS in Unity, one of which is metallic, one is reflective,

The former can be made of metal clay and the like, the latter for other non-metallic, but this is not absolute, the former can also make cloth wood and so on

The final use still depends on the artistic effect

(Metal PBR material in Unity)

(The reflection process in unity PBR material)

PBR procedure

Albedo map no light color map
Normal map Normal maps
Metallic map Metal map or specular map specular map

Roughness Roughness Map

3.19.2016 Content Corrections and updates

(Common material in Unity)

Traditional practices
Diffuse mapping Color Map
Specular Map Highlight Map
Normal map Normal maps

In the PBR process, the scene in the game will be more natural, and the calculation of lighting is more realistic. Will dominate in future offline rendering and real-time rendering, and a single material can simulate more real-world features

Of course, in the domestic framework is not very popular, most of the traditional way to make. The PBR process and the traditional difference is no longer using specular Map
In PBR is glossness (gloss can be interpreted as high gloss roughness) and metallicity (metal), the back of the two are basically gray-scale images, need to adjust the effect in the game engine, according to other online saying "The general company will be based on the project to send a material ball table, Albedo, The range of glossness,metallicity values is above, which is adjusted according to the physical properties of the item. ”
The process of mapping has changed and the model process has not changed much

Of course, here is the unity5, the default material is actually used PBS, the most obvious feature is the use of metallic, metal map (this in unity can be selected by the shader standard specular Setup to use Reflex version PBR) can also continue to use legacy legacy non-PBR material

Now, unity5 stickers.
Http://docs.unity3d.com/Manual/StandardShaderMaterialParameters.html
Albedo vs. diffuse map but not the same
The Natural color map (Albedo map) does not need illumination information, looks more flat, no highlight points, most do not need to overlay ao and the few black and white edges, only need to give the object surface natural color and very shallow texture only, a gloss map (GLOSS map) to show the object roughness (only related to roughness) , the coarser the darker the more white, a specular map to show the intrinsic reflective ability of the object, this is only related to the material, different items will give different materials of the high light color value range

Metallic Grayscale, is the special in PBR, it can be said that the feeling of metal it
Normal map body blue, normal map
Height map is a grayscale map here refers to Parallax mapping (parallax Mapping), of course, you can also place a bump map (bump map) or displacement map (displacement map)

Http://docs.unity3d.com/Manual/StandardShaderMaterialParameterHeightMap.html
The simple idea is that it's better to add a bump, a concept that wants normal mapping, but the technology is more complex,
Occlusion Map is a grayscale image that is used to protect high-light and indirect photographs, where indirect illumination comes from ambient light and reflected light,

Emission color Map self-illumination Map control surface light Emission this option also affects nearby objects, but to set the lighting inside is realtime, if it is baked dynamic object will not accept the light actually want to see the effect must be lit probe Then the glowing object must be static to see, otherwise it can only be seen by script refresh or otherwise.

Detail Mask Detail Picture mask
Secondary Maps
Detail Albedo Detail Color map
Normal Map Detail Map
These three are actually a set of objects in order to enlarge the level of detail to see the object, such as the skin of the pore map, and so on, the map is generally used repeat and repeated many times to achieve the details of the effect

There are two types of processes that you can choose
Reflection process

Process of metal degree

Mixing is no problem, of course, metal or reflective material is not the absolute use of choice
Specifically, look here.
http://blogs.unity3d.com/2015/02/18/working-with-physically-based-shading-a-practical-approach/
and the paint mapping tool.

Substance

http://quixel.se/

Now that we've talked about PBR, then combine the color space.

Linear and SRGB,HDR differences
The human eye has the light adaptive characteristic, this also can let the person in the dark scene to see more things, in the bright scene can distinguish more things, this effect generally from the movie theater such dim place to come out to be able to realize, the eye will have a slowly adapts the process. Now the camera will generally be adaptive exposure, but some of the industrial needs are not automatic, three-dimensional rendering, if the real full simulation of the image to the human eye to see, will feel more than our eyes see more gray, so generally in the hardware to do a reverse curve finally become sRGB color space to see.

Game engine inside the final effect to see, of course, is this enhanced to adapt to the human eye of the color space, but I do light calculation and mapping can not, because it will be due to a number of color enhancement resulting in a strong distortion of the final picture, this is the need to linear the color space, the calculation time with the real color, Until the output this step strengthens the color again to fit the human eye. Unity has long been a linear color space, but due to the last part of the final correction of many practitioners of the quality of the lack of, or completely without this awareness, the effect is completely incorrect, or lack of adjustment flexibility. Unreal, on the other hand, is almost an integrated and later color table in the workflow to solve the problem.

And HDR is the process of simulating the human eye, you can see a wider range of light (that is, when the light is brighter), the general color gamut of HDR image also exceeds the normal RGB gamut (but can not exceed). HDR in unity needs to tick the HDR option on the camera and use deferred rendering deferred (otherwise there will be a filter to show that the camera is not HDR enabled which is not using deferred rendering), to see the effect of adding a bloom and the like

(contrast chart in deferred rendering mode and HDR plus tonemapping (effects inside))

About the unity in the PBR technology and materials unity5 default shader and traditional comparison