Fix Z-order stacking of patches and axes grid lines (bug #40722). * gl-render.h (set_polygon_offset): Change function prototype for offset argument to float. * gl-render.cc (set_polygon_offset): Change offset argument to type float. Now matches OpenGL prototype for glPolygonOffset. * gl-render.cc (patch_tesselator::patch_tesselator): Change constructor variable idx to a float, from int. * gl-render.cc (patch_tesselator::begin): Pass index directly to set_polygon_offset. * gl-render.cc (opengl_renderer::draw_patch): Call patch_tesselator with index of 1.0 for filled portion of patch to push it down below outline of patch. * patch.m: For 2-D patches, set zlim to [-1,1] so that axes 'layer' property works.

#include <octave/oct.h>

DEFUN_DLD (helloworld, args, nargout,
           "Hello World Help String")
{
  int nargin = args.length ();

  octave_stdout << "Hello World has "
                << nargin << " input arguments and "
                << nargout << " output arguments.\n";

  return octave_value_list ();
}