FWIDTH(3G)

    .SH "NAME" fwidth - return the sum of the absolute value of derivatives in x and y
    .SH "DECLARATION"

            .HP u genType fwidth(genType p);
            .HP u genType fwidthCoarse(genType p);
            .HP u genType fwidthFine(genType p);

    .SH "PARAMETERS"

        .PP p

                    Specifies the expression of which to take the partial derivative.

            .RE

        .SH "DESCRIPTION"
            .PP Available only in the fragment shader, these functions return the sum of the absolute derivatives in $x$ and $y$ using local differencing for the input argument p. fwidth is equivalent to abs(dFdx(p)) + abs(dFdy(p)). fwidthCoarse is equivalent to abs(dFdxCoarse(p)) + abs(dFdyCoarse(p)). fwidthFine is equivalent to abs(dFdxFine(p)) + abs(dFdyFine(p)).

        .SH "VERSION SUPPORT"
            .TS allbox tab(:); lB cB s s s s s s s s s s s lB cB cB cB cB cB cB cB cB cB cB cB cB. T{ T}:T{ OpenGL Shading Language Version T} T{ Function Name T}:T{ 1.10 T}:T{ 1.20 T}:T{ 1.30 T}:T{ 1.40 T}:T{ 1.50 T}:T{ 3.30 T}:T{ 4.00 T}:T{ 4.10 T}:T{ 4.20 T}:T{ 4.30 T}:T{ 4.40 T}:T{ 4.50 T} l c c c c c c c c c c c c l c c c c c c c c c c c c. T{ fwidth T}:T{ ✔ T}:T{ ✔ T}:T{ ✔ T}:T{ ✔ T}:T{ ✔ T}:T{ ✔ T}:T{ ✔ T}:T{ ✔ T}:T{ ✔ T}:T{ ✔ T}:T{ ✔ T}:T{ ✔ T} T{ fwidthCoarse, fwidthFine T}:T{ - T}:T{ - T}:T{ - T}:T{ - T}:T{ - T}:T{ - T}:T{ - T}:T{ - T}:T{ - T}:T{ - T}:T{ - T}:T{ ✔ T}

        .SH "SEE ALSO"
            .PP dFdx()

        .SH "COPYRIGHT"
            .PP 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. https://opencontent.org/openpub/.

COPYRIGHT
Copyright © 2011-2014 Khronos Group