NAME

       smoothstep - perform Hermite interpolation between two values

DECLARATION

       genType smoothstep(genType edge0, genType edge1, genType x);

       genType smoothstep(float edge0, float edge1, genType x);

       genDType smoothstep(genDType edge0, genDType edge1, genDType x);

       genDType smoothstep(double edge0, double edge1, genDType x);

PARAMETERS

       edge0
           Specifies the value of the lower edge of the Hermite function.

       edge1
           Specifies the value of the upper edge of the Hermite function.

       x
           Specifies the source value for interpolation.

DESCRIPTION

       smoothstep performs smooth Hermite interpolation between 0 and 1 when edge0 < x < edge1.
       This is useful in cases where a threshold function with a smooth transition is desired.
       smoothstep is equivalent to:

               genType t;  /* Or genDType t; */
               t = clamp((x - edge0) / (edge1 - edge0), 0.0, 1.0);
               return t * t * (3.0 - 2.0 * t);

       Results are undefined if edge0 ≥ edge1.

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       │      │      │      │      │      │      │      │      │      │      │      │      │
       ├───────────┼──────┼──────┼──────┼──────┼──────┼──────┼──────┼──────┼──────┼──────┼──────┼──────┤
       │smoothstep │  -   │  -   │  ✔   │  ✔   │  ✔   │  ✔   │  ✔   │  ✔   │  ✔   │  ✔   │  ✔   │  ✔   │
       │(genType)  │      │      │      │      │      │      │      │      │      │      │      │      │
       ├───────────┼──────┼──────┼──────┼──────┼──────┼──────┼──────┼──────┼──────┼──────┼──────┼──────┤
       │smoothstep │  -   │  -   │  -   │  -   │  -   │  -   │  ✔   │  ✔   │  ✔   │  ✔   │  ✔   │  ✔   │
       │(genDType) │      │      │      │      │      │      │      │      │      │      │      │      │
       └───────────┴──────┴──────┴──────┴──────┴──────┴──────┴──────┴──────┴──────┴──────┴──────┴──────┘

SEE ALSO

       mix(), step()

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]                             07/22/2015                             SMOOTHSTEP(3G)