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NAME
faceforward - return a vector pointing in the same direction as another
DECLARATION
genType faceforward(genType N, genType I, genType Nref); genDType faceforward(genDType N, genDType I, genDType Nref);
PARAMETERS
N Specifies the vector to orient. I Specifies the incident vector. Nref Specifies the reference vector.
DESCRIPTION
faceforward orients a vector to point away from a surface as defined by its normal. If dot()(Nref, I) < 0 faceforward returns N, otherwise it returns -N.
VERSION SUPPORT
┌─────────────┬───────────────────────────────────────────────────────────────────────────────────┐ │ │ OpenGL Shading Language Version │ ├─────────────┼──────┬──────┬──────┬──────┬──────┬──────┬──────┬──────┬──────┬──────┬──────┬──────┤ │ Function │ 1.10 │ 1.20 │ 1.30 │ 1.40 │ 1.50 │ 3.30 │ 4.00 │ 4.10 │ 4.20 │ 4.30 │ 4.40 │ 4.50 │ │ Name │ │ │ │ │ │ │ │ │ │ │ │ │ ├─────────────┼──────┼──────┼──────┼──────┼──────┼──────┼──────┼──────┼──────┼──────┼──────┼──────┤ │ faceforward │ ✔ │ ✔ │ ✔ │ ✔ │ ✔ │ ✔ │ ✔ │ ✔ │ ✔ │ ✔ │ ✔ │ ✔ │ │ (genType) │ │ │ │ │ │ │ │ │ │ │ │ │ ├─────────────┼──────┼──────┼──────┼──────┼──────┼──────┼──────┼──────┼──────┼──────┼──────┼──────┤ │ faceforward │ - │ - │ - │ - │ - │ - │ ✔ │ ✔ │ ✔ │ ✔ │ ✔ │ ✔ │ │ (genDType) │ │ │ │ │ │ │ │ │ │ │ │ │ └─────────────┴──────┴──────┴──────┴──────┴──────┴──────┴──────┴──────┴──────┴──────┴──────┴──────┘
SEE ALSO
reflect(), refract()
COPYRIGHT
Copyright © 2011-2014 Khronos Group. This material may be distributed subject to the terms and conditions set forth in the Open Publication License, v 1.0, 8 June 1999. http://opencontent.org/openpub/.
COPYRIGHT
Copyright © 2011-2014 Khronos Group [FIXME: source] 01/03/2018 FACEFORWARD(3G)