NAME

       plgradient - Draw linear gradient inside polygon

SYNOPSIS

       plgradient(n, x, y, angle)

DESCRIPTION

       Draw  a  linear  gradient  using  cmap1  inside the polygon defined by the n points (x[i],
       y[i]).  Interpretation of the polygon is the same as  for  plfill(3plplot).   The  polygon
       coordinates and the gradient angle are all expressed in world coordinates.  The angle from
       the x axis for both the rotated coordinate system and the gradient vector is specified  by
       angle.   The  magnitude  of  the gradient vector is the difference between the maximum and
       minimum values of x for the vertices in the rotated coordinate system.  The origin of  the
       gradient  vector  can  be  interpreted  as being anywhere on the line corresponding to the
       minimum x value for the vertices in the rotated coordinate system.  The distance along the
       gradient  vector  is linearly transformed to the independent variable of color map 1 which
       ranges from 0. at the tail of the gradient vector to  1.  at  the  head  of  the  gradient
       vector.   What  is  drawn  is  the RGBA color corresponding to the independent variable of
       cmap1.  For more information about cmap1 (see the PLplot documentation).

       Redacted form: plgradient(x,y,angle)

       This function is used in examples 25 and 30.

ARGUMENTS

       n (PLINT(3plplot), input)
              Number of vertices in polygon.

       x (PLFLT_VECTOR(3plplot), input)
              A vector containing the x coordinates of vertices.

       y (PLFLT_VECTOR(3plplot), input)
              A vector containing the y coordinates of vertices.

       angle (PLFLT(3plplot), input)
              Angle (degrees) of gradient vector from x axis.

AUTHORS

       Many developers (who are credited at http://plplot.org/credits.php)  have  contributed  to
       PLplot over its long history.

SEE ALSO

       PLplot documentation at http://plplot.org/documentation.php.

                                           August, 2023                       PLGRADIENT(3plplot)