{"id":6743,"date":"2015-12-17T16:50:45","date_gmt":"2015-12-17T21:50:45","guid":{"rendered":"http:\/\/xplanedev.wpengine.com\/?post_type=article&p=6743"},"modified":"2020-01-06T07:59:44","modified_gmt":"2020-01-06T12:59:44","slug":"normal-maps","status":"publish","type":"article","link":"https:\/\/developer.x-plane.com\/article\/normal-maps\/","title":{"rendered":"Normal Maps"},"content":{"rendered":"

Definitions<\/span><\/h2>\n

A normal map is a texture that defines which way light bounces off a surface, on a per-pixel basis. Normal maps encode the direction of light reflections using RGB colors.<\/p>\n

A bump map is a texture that defines the height of bumps on a surface, on a per-pixel basis. Bump maps encode the height as a gray-scale image.<\/p>\n

X-Plane does not use bump maps; it only uses normal maps. See the Creating Normal Maps section below for information on creating normal maps from bump maps.<\/p>\n

A Specular Level Map (or shininess map) is a texture that defines which parts of a surface are shiny, on a per-pixel basis. (Specular maps are similar to ATTR_shiny_rat in their effect.) . Specular levels are a non-PBR X-Plane 10 concept.<\/p>\n

A Gloss Map defines which parts of a texture are\u00a0smooth, <\/em>and replace specular level maps in X-Plane 11.<\/p>\n

A “UV” map is the mapping of texture coordinates onto your model–that is, it is the shape of how your textures are applied to the mesh. X-Plane supports only one UV map per OBJ – that UV map is used for all textures: the day time (albedo), night LIT (emissive) and normal map textures.<\/p>\n

Format<\/span><\/h2>\n

X-Plane 10 uses combined normal and specular level maps in a single texture. The RGB of the texture are used for the normal map, and the alpha channel is used for the specular level.<\/p>\n

X-Plane’s normal maps are “tangent space” normal maps. That means that a “flat” (blue) normal map leaves the original surface unperturbed.<\/p>\n

Creating Normal Maps<\/span><\/h2>\n

NormalMappr<\/span><\/h3>\n

NormalMappr is a free program for OS X that converts bump-maps to tangent-space normal maps. You open a PNG file, adjust a few parameters, and then save the results. You can apply it to a custom-drawn bump map (drawn in gray-scale using PhotoShop) or simply apply it to your RGB textures.<\/p>\n

http:\/\/shamyl.zakariya.net\/apps\/NormalMappr.zip<\/a><\/p>\n

Converting Normal Maps From FS X Aircraft<\/span><\/h3>\n

FSX and X-Plane do not use the same normal map format. There are three key differences:<\/p>\n