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Cutting edge AAA shading technology for all

November 21, 2013 in Games | 3 min. read

Physically-based surface shaders in the Asset Store

So… physically-based surface shaders. Physically-based what? I hear you say. Even though we consider ourselves a company with its finger firmly on the gaming pulse, some of us had to have this explained (not the graphics team I hasten to add).

Physically-based surface shaders are a revolutionary (and really cool) way of doing shading that generate far more realistic and vibrant results. What distinguishes them from other shaders is that they actually mimic the behaviour of surfaces in the real world by following the law of energy conservation: the total amount of specular and diffuse reflection always equals the amount of incoming lighting energy.

The huge advantage of physically-based surface shaders isn’t just the exceptional visual fidelity they achieve, it’s that they look incredibly lifelike irrespective of the lighting conditions under which they’re used. Steel will look like steel whether it’s reflecting bright sunlight off a knight’s breastplate or used in a handrail on a dark and dreary New York backstreet. There’s no need to adjust your shader settings to get things looking ‘right’ when authoring different environments.

Physically based surfaces can have a wide range of reflective behaviour, making it easier to give shiny plastic, metal, wet stone and everything in between a unique visual identity. The Alloy Physical Shader Framework by RUST LTD, available now on the Unity Asset Store, brings this technology to Unity Pro.

Physically-based surface shaders are finding their way into many of the latest AAA productions like Killzone 3, Metal Gear Solid 5 and RYSE. RUST LTD’s Asset Store product is different in that it makes this technology accessible to small teams - or even individuals. By the way, RUST LTD are the team behind Museum of the Microstar - our DX11 contest winning entry. Museum of the Microstar used an earlier version of Alloy and showed its use scaled to intense heights.


The workaholic perfectionists at RUST LTD have spent 2 years working day and night to get the product to the point where they’re happy enough to release it, and somehow they’ve also found the time to come up with lots of learning material to help you guys get started. The Alloy package ships with a comprehensive sample scene, including over 30 complete materials with interactive controls so you can get up to speed fast on how to get the most out the set. Also, if you find yourself needing even more out of Alloy, the set is configured to make extending it with your own variants as easy as possible.

<br><b><i>“Being indie, and having worked so much with small teams and students, we wanted to make a tool that people like us could use. Artists and game designers without the resources of a full studio behind them now have accessible tools."<br>Anton Hand, Beard Warrior at RUST LTD.</i></b>

Alloy is built around a Normalized Blinn-Phong BRDF, which provides a great balance of speed and sophistication, and is fully compatible with DX9 and the light pre-pass renderer of Unity’s deferred mode. The Alloy set contains variants for all the common visual characteristics you might need including rim lighting, separated occlusion maps, detail maps, and several types of translucency.

Lastly, for those who don’t want the headache of managing cubemaps in complex environments, Alloy includes a complete set that uses Radially Symmetric Reflection Maps (RSRMs), a general-purpose blurred reflection texture that makes baked surfaces look shiny, without looking like perfect mirrors.

In an upcoming post we’ll dive deeper into both the technical details of Alloy, and the implications of developing content for a physically-based pipeline... stay tuned!

So, whether you’re a large team looking for that AAA graphics punch for your next-gen console game, or an indie trying to add wow factor, Alloy is ready for you. Check out these downloadable projects and demos made with Alloy, or simply purchase directly from the Asset Store.

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November 21, 2013 in Games | 3 min. read