Physical based rendering is a fairly new technique used in the 3d software industry and has been used on a few games already. A few notable example are Star citizen, Rise, sunset overdrive to name a few. It is becoming increasing common for game companies to take advantage of this technique due to the amount of realism it provides over previous techniques. Not only this but it is also being used in the market industry in order to sell products, which would usually be displayed through a photograph. But due to the cost of the studio setting, shipping the products it is easier and cheaper to use a extremely detailed, accurate physically based render which looks photorealistic.
It allows lighting to be optimised more accurately as it hits surfaces in order to create better efficiency. Another benefit of this, like I said above is how much more photorealistic it looks compared to using different specular maps on individual materials, which takes longer than just using physical based rendering. It can also be rendered in near real time providing speed and efficiency whilst modelling. It also uses image based rendering which means that it will take light from the environment around it, which results in different colors reflecting of the object. So if the object I am modelling is set in a forest, it will have a greener tone to it and may vary depending on the intensity of light reflecting different times of day. Here’s an image by LeoTS to give you an idea of what I mean –
As you can see from this image the colour of the floor is being reflected with accurate colours of the sphere along with the back having a greener darker tone being in the shade.
It does all of this by having a diffuse reflection were light hits an object and bounces of with some wavelengths being absorbed and the rest leaving. Speculator provides and instant reflection of an object.
Crytek are pushing this forward with their cryengine allowing this to become more mainstream as more developers use this tool, which shall advance and mature this technique as time goes on. Within this engine every non metal has its own spec map and every metal has colour in its spec map. Due to its efficiency the performance is better meaning that within a game, not only will it look better, but you can squeeze more performance out which could be used for a faster frame rate or more detail.
As you can see with this image from Sketchfab, PBR provides greater accuracy and better lighting than using older methods.
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