NAME

       notcurses_lines - operations on lines and boxes

SYNOPSIS

       #include <notcurses/notcurses.h>

       int ncplane_hline_interp(struct ncplane* n, const nccell* c, unsigned len, uint64_t c1, uint64_t c2);

       static inline int ncplane_hline(struct ncplane* n, const nccell* c, unsigned len);

       int ncplane_vline_interp(struct ncplane* n, const nccell* c, unsigned len, uint64_t c1, uint64_t c2);

       static inline int ncplane_vline(struct ncplane* n, const nccell* c, unsigned len);

              #define NCBOXMASK_TOP    0x0001
              #define NCBOXMASK_RIGHT  0x0002
              #define NCBOXMASK_BOTTOM 0x0004
              #define NCBOXMASK_LEFT   0x0008
              #define NCBOXGRAD_TOP    0x0010
              #define NCBOXGRAD_RIGHT  0x0020
              #define NCBOXGRAD_BOTTOM 0x0040
              #define NCBOXGRAD_LEFT   0x0080
              #define NCBOXCORNER_MASK 0x0300
              #define NCBOXCORNER_SHIFT 8u

       int  ncplane_box(struct  ncplane*  n, const nccell* ul, const nccell* ur, const nccell* ll, const nccell*
       lr, const nccell* hline, const nccell* vline, int ystop, int xstop, unsigned ctlword);

       static inline int ncplane_box_sized(struct ncplane* n, const nccell* ul, const nccell* ur, const  nccell*
       ll, const nccell* lr, const nccell* hline, const nccell* vline, int ylen, int xlen, unsigned ctlword);

       static  inline int ncplane_perimeter(struct ncplane* n, const nccell* ul, const nccell* ur, const nccell*
       ll, const nccell* lr, const nccell* hline, const nccell* vline, unsigned ctlword)

       static inline int nccells_load_box(struct ncplane* n, uint16_t styles, uint64_t channels, nccell* ul, nc‐
       cell* ur, nccell* ll, nccell* lr, nccell* hl, nccell* vl, const char* gclusters);

       static inline int nccells_rounded_box(struct ncplane* n, uint16_t styles, uint64_t channels, nccell*  ul,
       nccell* ur, nccell* ll, nccell* lr, nccell* hl, nccell* vl);

       static  inline  int ncplane_rounded_box(struct ncplane* n, uint16_t styles, uint64_t channels, int ystop,
       int xstop, unsigned ctlword);

       static inline int ncplane_rounded_box_sized(struct ncplane* n, uint16_t styles,  uint64_t  channels,  int
       ylen, int xlen, unsigned ctlword);

       static  inline  int nccells_double_box(struct ncplane* n, uint16_t styles, uint64_t channels, nccell* ul,
       nccell* ur, nccell* ll, nccell* lr, nccell* hl, nccell* vl);

       static inline int ncplane_double_box(struct ncplane* n, uint16_t styles, uint64_t  channels,  int  ystop,
       int xstop, unsigned ctlword);

       static  inline  int  ncplane_double_box_sized(struct  ncplane* n, uint16_t styles, uint64_t channels, int
       ylen, int xlen, unsigned ctlword);

       int ncplane_polyfill_yx(struct ncplane* n, unsigned y, unsigned x, const nccell* c);

       int ncplane_gradient(struct ncplane* n, int y, int x, unsigned ylen,  unsigned  xlen,  const  char*  egc,
       uint16_t stylemask, uint64_t ul, uint64_t ur, uint64_t ll, uint64_t lr);

       int  ncplane_highgradient2x1(struct  ncplane* n, int y, int x, unsigned ylen, unsigned xlen, uint32_t ul,
       uint32_t ur, uint32_t ll, uint32_t lr);

       int ncplane_format(struct ncplane* n, int y, int x, unsigned ylen, unsigned xlen, uint16_t stylemask);

       int ncplane_stain(struct ncplane* n, int y, int x, unsigned ylen, unsigned xlen,  uint64_t  ul,  uint64_t
       ur, uint64_t ll, uint64_t lr);

DESCRIPTION

       ncplane_polyfill_yx starts at the specified y and x (provide -1 to use the cursor's position in the rele‐
       vant  dimension).  The cell at these coordinates is replaced with c.  All connected cells having the same
       content as this original cell are replaced with c, recursively.  Two cells are connected if they are ver‐
       tical or horizontal neighbors of one another.

       ncplane_gradient replaces all glyphs in the specified area with egc, and colors them with  the  specified
       gradient.  All content within the specified area is destroyed.

       ncplane_gradient2x1  draws  a high-definition gradient in the specified area.  It will return an error if
       UTF8 is not being used.  The gradient is drawn using the UPPER HALF BLOCK glyph, with two vertical  steps
       and  one  horizontal step in each cell.  Since cells are often about twice as tall as they are wide, this
       tends to result in very even color differences.  All content within the specified area is destroyed.

       ncplane_format sets the attributes of every cell in the region having its upper-left corner at  y  and  x
       (provide  -1  to  use  the cursor's position in the relevant dimension), and its area defined by ylen and
       xlen (provide 0 to use all remaining area to the right and below,  respectively).   Channels  and  glyphs
       will be unaffected.

       ncplane_stain  works  the  same way, but sets channels.  Standard linear interpolation is applied between
       the provided corner channels.  Glyphs and their attributes will be unaffected.

       Box- and line-drawing is unaffected by a plane's scrolling status.

RETURN VALUES

       ncplane_format, ncplane_stain, ncplane_gradient, ncplane_gradient2x1, and ncplane_polyfill_yx  return  -1
       if any coordinates are outside the plane, and otherwise the number of cells affected.

       ncplane_hline_interp,  ncplane_hline,  ncplane_vline_interp,  and  ncplane_vline all return the number of
       glyphs drawn on success, or -1 on failure.  Passing a length of 0 is an error.

SEE ALSO

       notcurses(3), notcurses_cell(3), notcurses_plane(3)

AUTHORS

       nick black <nickblack@linux.com>.

                                                     v3.0.7                                   notcurses_lines(3)