czm_normal3D

czm_normal3D

An automatic GLSL uniform representing a 3x3 normal transformation matrix that transforms normal vectors in 3D model coordinates to eye coordinates. In 3D mode, this is identical to czm_normal, but in 2D and Columbus View it represents the normal transformation matrix as if the camera were at an equivalent location in 3D mode. This is useful for lighting 2D and Columbus View in the same way that 3D is lit.

Positions should be transformed to eye coordinates using czm_modelView3D and normals should be transformed using czm_normal3D.

Example
// GLSL declaration
uniform mat3 czm_normal3D;

// Example
vec3 eyeNormal = czm_normal3D * normal;
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