Ambient Occlusion is applied to ambient lighting while Cavity Occlusion is applied to the diffuse and specular lighting. The Occlusion map holds Ambient Occlusion in the red channel and Cavity Occlusion in the green channel with the blue and alpha channels remaining empty. The Occlusion map is a new addition and is denoted by the basename followed by the -ao suffix (XXX-ao.dds). Vanadium Steel is different from High Carbon Steel). Some metals have different specular values depending upon the purity of the material or additional alloying materials (e.g. Metals tend to have high, colored specular values, while dielectrics tend to have low, gray specular values. Any material can be glossy or matte, use gloss as you see fit, especially for scratches and buffs. Reflectance maps contain specular colors in the RGB channels and gloss information in the alpha channel. The Reflectance map replaces the shine map and is denoted by the basename followed by the -reflect suffix (XXX-reflect.dds). Gold is a perfect example for this, as it has a diffuse color of (36,13,3). Additionally, some metals do have colored diffuse. For example, Silver has a diffuse of (30,30,30), making it a dark gray, while Steel and Aluminum have even darker diffuse colors at (5,5,5) and (13,13,13) respectively. This is misleading because many metals actually have visibly gray diffuse colors.

The link at the top of this article states that metals should have a black diffuse/albedo. Albedo maps contain no lighting information, so you will not multiply your ambient occlusion map into it. The Albedo map replaces the diffuse map and is denoted by the basename texture (XXX.dds).

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