message: Explains sq() in code snippet
  Closes
diff: @@ -975,7 +975,8 @@ float D_GGX_Anisotropic(float NoH, const vec3 h,
  float BoH = dot(b, h);
  float a2 = at * ab;
  vec3 v = vec3(ab * ToH, at * BoH, a2 * NoH);
  - return a2 * sqr(a2 / dot(v, v)) * (1.0 / PI);
  + // sq(x) returns x^2
  + return a2 * sq(a2 / dot(v, v)) * (1.0 / PI);
  }
  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  [Listing [anisotropicBRDF]: Implementation of Burley's anisotropic NDF in GLSL]
  