Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages

  
 
  

home | help
notcurses_plane(3)					    notcurses_plane(3)

NAME
       notcurses_plane - operations on ncplanes

SYNOPSIS
       #include	<notcurses/notcurses.h>

	      #define NCPLANE_OPTION_HORALIGNED	  0x0001ull
	      #define NCPLANE_OPTION_VERALIGNED	  0x0002ull
	      #define NCPLANE_OPTION_MARGINALIZED 0x0004ull
	      #define NCPLANE_OPTION_FIXED	  0x0008ull
	      #define NCPLANE_OPTION_AUTOGROW	  0x0010ull
	      #define NCPLANE_OPTION_VSCROLL	  0x0020ull

	      typedef struct ncplane_options {
		int y;		  // vertical placement	relative to parent plane
		int x;		  // horizontal	placement relative to parent plane
		int rows;	  // number of rows, must be positive
		int cols;	  // number of columns,	must be	positive
		void* userptr;	  // user curry, may be	NULL
		const char* name; // name (used	only for debugging), may be NULL
		int (*resizecb)(struct ncplane*); // called on parent resize
		uint64_t flags;	  // closure over NCPLANE_OPTION_*
		unsigned margin_b, margin_r; //	bottom and right margins
	      }	ncplane_options;

	      #define NCSTYLE_MASK	0xffffu
	      #define NCSTYLE_ITALIC	0x0010u
	      #define NCSTYLE_UNDERLINE	0x0008u
	      #define NCSTYLE_UNDERCURL	0x0004u
	      #define NCSTYLE_BOLD	0x0002u
	      #define NCSTYLE_STRUCK	0x0001u
	      #define NCSTYLE_NONE	0

       struct  ncplane*	 ncplane_create(struct	ncplane*  n, const ncplane_op-
       tions* nopts);

       struct ncplane* ncpile_create(struct notcurses*	n,  const  ncplane_op-
       tions* nopts);

       struct  ncplane*	 ncplane_reparent(struct  ncplane*  n, struct ncplane*
       newparent);

       struct ncplane* ncplane_reparent_family(struct ncplane* n,  struct  nc-
       plane* newparent);

       int ncplane_descendant_p(const struct ncplane* n, const struct ncplane*
       ancestor);

       int ncplane_resize_realign(struct ncplane* n);

       int ncplane_resize_maximize(struct ncplane* n);

       int ncplane_resize_marginalized(struct ncplane* n);

       int ncplane_resize_placewithin(struct ncplane* n);

       void  ncplane_set_resizecb(struct  ncplane* n, int(resizecb)(struct nc-
       plane));

       int (ncplane_resizecb(const struct ncplane n**))(struct ncplane*);**

       struct ncplane* ncplane_dup(struct ncplane* n, void* opaque);

       int ncplane_resize(struct ncplane* n, int keepy,	int keepx, int keeple-
       ny, int keeplenx, int yoff, int xoff, int ylen, int xlen);

       int ncplane_move_yx(struct ncplane* n, int y, int x);

       int ncplane_move_rel(struct ncplane* n, int y, int x);

       void ncplane_yx(const struct ncplane* n,	int* restrict y, int* restrict
       x);

       int ncplane_y(const struct ncplane* n);

       int ncplane_x(const struct ncplane* n);

       void ncplane_abs_yx(const struct	ncplane* n, int* y, int* x);

       int ncplane_abs_y(const struct ncplane* n);

       int ncplane_abs_x(const struct ncplane* n);

       struct ncplane* ncplane_parent(struct ncplane* n);

       const struct ncplane* ncplane_parent_const(const	struct ncplane*	n);

       int ncplane_set_base_cell(struct	ncplane* ncp, const nccell* c);

       int ncplane_set_base(struct ncplane* ncp,  const	 char*	egc,  uint16_t
       stylemask, uint64_t channels);

       int ncplane_base(struct ncplane*	ncp, nccell* c);

       static inline void ncplane_move_top(struct ncplane* n);

       static inline void ncplane_move_bottom(struct ncplane* n);

       void ncplane_move_family_top(struct ncplane* n);

       void ncplane_move_family_bottom(struct ncplane* n);

       int  ncplane_move_above(struct ncplane* restrict	n, struct ncplane* re-
       strict targ);

       int ncplane_move_below(struct ncplane* restrict n, struct ncplane*  re-
       strict targ);

       int  ncplane_move_family_above(struct  ncplane*	restrict n, struct nc-
       plane* restrict targ);

       int ncplane_move_family_below(struct ncplane* restrict  n,  struct  nc-
       plane* restrict targ);

       struct ncplane* ncplane_below(struct ncplane* n);

       struct ncplane* ncplane_above(struct ncplane* n);

       char*   ncplane_at_cursor(struct	  ncplane*   n,	 uint16_t*  stylemask,
       uint64_t* channels);

       int ncplane_at_cursor_cell(struct ncplane* n, nccell* c);

       char* ncplane_at_yx(const struct	ncplane* n, int	y,  int	 x,  uint16_t*
       stylemask, uint64_t* channels);

       int ncplane_at_yx_cell(struct ncplane* n, int y,	int x, nccell* c);

       uint32_t*  ncplane_as_rgba(const	 struct	ncplane* nc, ncblitter_e blit,
       unsigned	begy, unsigned begx, unsigned leny, unsigned  lenx,  unsigned*
       pxdimy, unsigned* pxdimx);

       char*  ncplane_contents(const  struct  ncplane* nc, int begy, int begx,
       unsigned	leny, unsigned lenx);

       void* ncplane_set_userptr(struct	ncplane* n, void* opaque);

       void* ncplane_userptr(struct ncplane* n);

       void ncplane_dim_yx(const struct	ncplane* n, unsigned*  restrict	 rows,
       unsigned* restrict cols);

       static inline unsigned ncplane_dim_y(const struct ncplane* n);

       static inline unsigned ncplane_dim_x(const struct ncplane* n);

       void  ncplane_cursor_yx(const  struct ncplane* n, unsigned* restrict y,
       unsigned* restrict x);

       unsigned	ncplane_cursor_y(const struct ncplane* n);

       unsigned	ncplane_cursor_x(const struct ncplane* n);

       void ncplane_translate(const struct ncplane* src, const struct ncplane*
       dst, int* restrict y, int* restrict x);

       bool ncplane_translate_abs(const	struct ncplane*	n,  int*  restrict  y,
       int* restrict x);

       uint64_t	ncplane_channels(const struct ncplane* n);

       void ncplane_set_channels(struct	ncplane* nc, uint64_t channels);

       static inline unsigned ncplane_bchannel(struct ncplane* nc);

       static inline unsigned ncplane_fchannel(struct ncplane* nc);

       uint64_t	ncplane_set_bchannel(struct ncplane* nc, uint32_t channel);

       uint64_t	ncplane_set_fchannel(struct ncplane* nc, uint32_t channel);

       static inline unsigned ncplane_fg_rgb(struct ncplane* nc);

       static inline unsigned ncplane_bg_rgb(struct ncplane* nc);

       int ncplane_set_fg_rgb(struct ncplane* n, uint32_t channel);

       int ncplane_set_bg_rgb(struct ncplane* n, uint32_t channel);

       static inline unsigned ncplane_fg_alpha(struct ncplane* nc);

       static inline unsigned ncplane_bg_alpha(struct ncplane* nc);

       int ncplane_set_fg_alpha(struct ncplane*	n, unsigned alpha);

       int ncplane_set_bg_alpha(struct ncplane*	n, unsigned alpha);

       static  inline unsigned ncplane_fg_rgb8(struct ncplane* n, unsigned* r,
       unsigned* g, unsigned* b);

       static inline unsigned ncplane_bg_rgb8(struct ncplane* n, unsigned*  r,
       unsigned* g, unsigned* b);

       int  ncplane_set_fg_rgb8(struct ncplane*	n, unsigned r, unsigned	g, un-
       signed b);

       int ncplane_set_bg_rgb8(struct ncplane* n, unsigned r, unsigned g,  un-
       signed b);

       void  ncplane_set_fg_rgb8_clipped(struct	 ncplane* n, int r, int	g, int
       b);

       void ncplane_set_bg_rgb8_clipped(struct ncplane*	n, int r, int  g,  int
       b);

       void ncplane_set_fg_default(struct ncplane* n);

       void ncplane_set_bg_default(struct ncplane* n);

       int ncplane_set_fg_palindex(struct ncplane* n, unsigned idx);

       int ncplane_set_bg_palindex(struct ncplane* n, unsigned idx);

       uint16_t	ncplane_styles(const struct ncplane* n);

       void ncplane_set_styles(struct ncplane* n, unsigned stylebits);

       void ncplane_on_styles(struct ncplane* n, unsigned stylebits);

       void ncplane_off_styles(struct ncplane* n, unsigned stylebits);

       void ncplane_greyscale(struct ncplane* n);

       int  ncplane_blit_bgrx(struct  ncplane* nc, int placey, int placex, int
       linesize, ncblitter_e blitter, const unsigned char* data, int begy, int
       begx, int leny, int lenx);

       int ncplane_blit_rgba(struct ncplane* nc, int placey, int  placex,  int
       linesize, ncblitter_e blitter, const unsigned char* data, int begy, int
       begx, int leny, int lenx);

       int ncplane_destroy(struct ncplane* ncp);

       void notcurses_drop_planes(struct notcurses* nc);

       int  ncplane_mergedown(struct  ncplane*	src,  struct ncplane* dst, int
       begsrcy,	int begsrcx, unsigned  leny,  unsigned	lenx,  int  dsty,  int
       dstx);

       int  ncplane_mergedown_simple(struct  ncplane* restrict src, struct nc-
       plane* restrict dst);

       void ncplane_erase(struct ncplane* n);

       int ncplane_erase_region(struct ncplane*	n, int ystart, int xstart, int
       ylen, int xlen);

       bool ncplane_set_scrolling(struct ncplane* n, unsigned scrollp);

       bool ncplane_scrolling_p(const struct ncplane* n);

       bool ncplane_set_autogrow(struct	ncplane* n, unsigned growp);

       bool ncplane_autogrow_p(const struct ncplane* n);

       int ncplane_scrollup(struct ncplane* n, int r);

       int ncplane_scrollup_child(struct ncplane*  n,  const  struct  ncplane*
       child);

       int ncplane_rotate_cw(struct ncplane* n);

       int ncplane_rotate_ccw(struct ncplane* n);

       void  ncplane_pixel_geom(const  struct notcurses* n, unsigned* restrict
       pxy, unsigned* restrict pxx, unsigned* restrict celldimy, unsigned* re-
       strict  celldimx,  unsigned*  restrict  maxbmapy,  unsigned*   restrict
       maxbmapx);

       int ncplane_set_name(struct ncplane* n, const char* name);

       char* ncplane_name(const	struct ncplane*	n);

DESCRIPTION
       Ncplanes	 are  the fundamental drawing object of	notcurses.  All	output
       functions take a	struct ncplane as an argument.	They can be any	 size,
       and placed anywhere.  In	addition to its	framebuffer--a rectilinear ma-
       trix of nccells (see notcurses_cell(3))--an ncplane is defined by:

        a base	nccell,	used for any cell on the plane without a glyph,

        the egcpool backing its nccells,

        a current cursor location,

        a current style, foreground channel, and background channel,

        its geometry,

        a configured user pointer,

        position relative to the standard plane,

        the plane, if any, to which it	is bound,

        the next plane	bound by the plane to which it is bound,

        the head of the list of its bound planes,

        its resize methodology,

        whether a sprixel (see	notcurses_visual(3)) is	associated,

        its z-index, and

        a name	(used only for debugging).

       New  planes can be created with ncplane_create.	If a plane is bound to
       another,	x and y	coordinates are	relative to the	plane to which	it  is
       bound,  and if this latter plane	moves, all its bound planes move along
       with it.	 When a	plane is destroyed, all	planes bound to	 it  (directly
       or transitively)	are destroyed.

       If  the NCPLANE_OPTION_HORALIGNED flag is provided, x is	interpreted as
       an ncalign_e rather than	an  absolute  position.	  If  the  NCPLANE_OP-
       TION_VERALIGNED	flag  is  provided,  y	is interpreted as an ncalign_e
       rather than an absolute postiion.  Either way, all positions are	 rela-
       tive  to	 the  parent  plane.  ncplane_resize_realign should usually be
       used together with these	flags, so that the plane is automatically  re-
       aligned upon a resize of	its parent.

       If  the	NCPLANE_OPTION_MARGINALIZED  flag  is  provided,  neither  NC-
       PLANE_OPTION_HORALIGNED nor NCPLANE_OPTION_VERALIGNED may be  provided,
       and  rows  and cols must	both be	0.  y and x will be interpreted	as top
       and left	margins.  margin_b and margin_r	will be	interpreted as	bottom
       and right margins.  The plane will take the maximum space possible sub-
       ject  to	 its parent planes and these margins.  The plane cannot	become
       smaller than 1x1	(the margins are best-effort).	ncplane_resize_margin-
       alized should usually be	used together with  this  flag,	 so  that  the
       plane is	automatically resized.

       ncplane_reparent	 detaches  the	plane  n from any plane	to which it is
       bound, and binds	it to newparent.  Its children are reparented  to  its
       previous	 parent.  The standard plane cannot be reparented.  If newpar-
       ent is NULL, the	plane becomes the root	plane  of  a  new,  unrendered
       stack.	When  ncplane_reparent_family  is  used, all planes bound to n
       move along with it during a reparenting operation.  See Piles below.

       ncplane_destroy destroys	a particular ncplane, after which it must  not
       be  used	again.	notcurses_drop_planes destroys all ncplanes other than
       the stdplane.  Any references to	such planes are, of course, invalidat-
       ed.  It is undefined to destroy a plane concurrently with any other op-
       eration involving that plane, or	any operation involving	the z-axis.

       It is an	error for two threads to concurrently mutate a single ncplane.
       So long as rendering is not taking place, however, multiple threads may
       safely output to	multiple ncplanes.  So long as all threads  are	 read-
       ers,  multiple threads may work with a single ncplane.  A reading func-
       tion is any which accepts a const struct	ncplane.

       A plane can be moved relative to	its parent  plane's  origin  with  nc-
       plane_move_yx.  If the plane has	no parent, the move is relative	to the
       rendering  area.	  A  plane  can	be moved off-screen entirely, in which
       case it will not	be visible following rasterization;  it	 can  also  be
       partially off-screen.

       A  plane	 has  a	virtual	cursor;	Set its	new position with ncplane_cur-
       sor_move_yx.  Specifying	-1 as one or both coordinates will  hold  that
       axis  constant.	 You may move a	cursor relatively to its current posi-
       tion with ncplane_cursor_move_rel.  Unless  coordinates	are  specified
       for a call, action takes	place at the plane's virtual cursor, which au-
       tomatically  moves along	with output.  The current virtual cursor loca-
       tion can	be acquired with ncplane_cursor_yx.

       ncplane_yx returns the coordinates of  the  specified  plane's  origin,
       relative	 to the	plane to which it is bound.  Either or both of y and x
       may be NULL.  ncplane_y and ncplane_x allow a single component of  this
       location	 to  be	 retrieved.  ncplane_abs_yx returns the	coordinates of
       the specified plane's origin relative to	its pile.

       ncplane_translate translates  coordinates  expressed  relative  to  the
       plane  src,  and	 writes	 the coordinates of that cell relative to dst.
       The cell	need not intersect with	dst, though this  will	yield  coordi-
       nates which are invalid for writing or reading on dst.  If dst is NULL,
       it  is  taken  to  refer	 to the	standard plane.	 ncplane_translate_abs
       takes coordinates expressed relative to the standard plane, and returns
       coordinates relative to dst, returning false if the coordinates are in-
       valid for dst.

       ncplane_mergedown writes	to dst the frame that would be rendered	if on-
       ly src and dst existed on the z-axis, ad	dst represented	 the  entirety
       of  the	rendering  region.  Only those cells where src intersects with
       dst might see changes.  It is an	error to merge a plane onto itself.

       ncplane_erase zeroes out	every cell of the plane,  dumps	 the  egcpool,
       and  homes  the	cursor.	 The base cell is preserved, as	are the	active
       attributes.  ncplane_erase_region does the same for a subregion of  the
       plane.	For the	latter,	supply 0 for ylen and/or xlen to erase through
       that dimension, starting	at the specified point.	 Supply	-1 for	ystart
       and/or  xstart to use the cursor's current position along that axis for
       a starting point.  Negative ylen	and xlen move up and to	the left  from
       the  starting  coordinate;  positive ylen and xlen move down and	to the
       right from same.	 See BUGS below.

       When a plane is resized (whether	by ncplane_resize,  SIGWINCH,  or  any
       other mechanism), a depth-first recursion is performed on its children.
       Each  child plane having	a non-NULL resizecb will see that callback in-
       voked following resizing	of its parent's	plane.	If it returns  non-ze-
       ro,  the	 resizing  cascade terminates, returning non-zero.  Otherwise,
       resizing	proceeds recursively.

       ncplane_move_top	and ncplane_move_bottom	extract	their argument n  from
       the  z-axis, and	reinsert it at the top or bottom, respectively,	of its
       pile.  These functions are both O(1).  ncplane_move_family_top and  nc-
       plane_move_family_bottom	 do  the  same,	and move any bound descendants
       along with the plane.  Ordering among the  plane	 and  its  descendants
       will  be	 maintained.   For example, assume a pile with A at the	top of
       its z-axis, followed by B, C, D,	and E, where E is bound	to C.  Calling
       ncplane_move_family_top on C will result	in the order  CEABD.   Calling
       ncplane_move_family_bottom  on C	will result in the order ABDCE.	 Call-
       ing ncplane_move_family_top or ncplane_move_top on  E  will  result  in
       EABCD.	Calling	ncplane_move_family_bottom on E	is a no-op.  These two
       functions are O(N) on the number	of planes in the pile.

       ncplane_move_above and ncplane_move_below move the argument n above  or
       below, respectively, the	argument targ.	Both operate in	O(1).

       ncplane_at_yx and ncplane_at_yx_cell retrieve the contents of the plane
       at  the	specified  coordinate.	 The content is	returned as it will be
       used during rendering, and thus integrates any base cell	 as  appropri-
       ate.  If	called on the secondary	columns	of a wide glyph, ncplane_at_yx
       returns the EGC,	and thus cannot	be used	to distinguish between primary
       and secondary columns.  ncplane_at_yx_cell, however, preserves this in-
       formation:  retrieving  a  secondary  column  of	 a wide	glyph with nc-
       plane_at_yx_cell	will fill in the nccell	argument such that  nccell_ex-
       tended_gcluster(3)  returns an empty string, and	nccell_wide_right_p(3)
       returns true.

       If ncplane_at_yx	is invoked upon	a sprixel plane, the control  sequence
       will be returned	for any	valid coordinates (note	that this may be quite
       large).	 This  does not	apply to ncplane_at_yx_cell, which will	return
       an error.

       ncplane_set_name	sets the plane's name, freeing any old name.  name may
       be NULL.	 ncplane_set_name duplicates the provided name internally.

   Base	cells
       Each plane has a	base cell, initialized to all zeroes.  When rendering,
       the cells of the	plane are examined in turn.  Each cell has three inde-
       pendent rendering elements--its EGC, its	foreground  channel,  and  its
       background  channel.   Any  default channel is replaced with the	corre-
       sponding	channel	from that plane's base cell.  ncplane_erase has	no ef-
       fect on the base	cell.  Calling ncplane_erase on	 a  plane  whose  base
       cell  is	 a purple 'A' results (for rendering purposes) in a plane made
       up entirely of purple 'A's.

       ncplane_set_base_cell uses the nccell c (which must be bound to the nc-
       plane ncp, and must be the first	nccell of a multicolumn	 sequence)  to
       set the base cell.  ncplane_set_base does the same with egc, stylemask,
       and channels.

   Piles
       A  single notcurses context is made up of one or	more piles.  A pile is
       a set of	one or more ncplanes, including	the partial orderings made  up
       of  their binding and z-axis pointers.  A pile has a top	and bottom nc-
       plane (this might be a single plane),  and  one	or  more  root	planes
       (planes	which  are bound to themselves).  Multiple threads can concur-
       rently operate on distinct piles, even changing one while rendering an-
       other.

       Each plane is part of one and only one pile.  By	default,  a  plane  is
       part  of	 the same pile containing that plane to	which it is bound.  If
       ncpile_create is	used in	the  place  of	ncplane_create,	 the  returned
       plane becomes the root plane, top, and bottom of	a new pile.  As	a root
       plane, it is bound to itself.  A	new pile can also be created by	repar-
       enting  a plane to itself, though if the	plane is already a root	plane,
       this is a no-op.

       When a plane is moved to	a different pile (whether new or preexisting),
       any planes which	were bound to it are rebound to	its  previous  parent.
       If  the	plane  was  a root plane of some pile, any bound planes	become
       root planes.  The new plane is placed immediately atop its  new	parent
       on  its	new  pile's z-axis.  When ncplane_reparent_family is used, all
       planes bound to the reparented plane are	moved along  with  it.	 Their
       relative	z-order	is maintained.

       More information	is available from notcurses_pile(3).

   Binding
       The  planes  of a pile make up a	directed acyclic forest.  Planes bound
       to themselves make up the root planes of	the pile.  Every plane is  ei-
       ther  a	root plane, or bound to	some other plane in its	pile.  A plane
       and its descendants make	up a family.  When a plane is moved using  nc-
       plane_move_yx, its family is moved along	with it.

   Scrolling
       All  planes,  including	the standard plane, are	created	with scrolling
       disabled.   Control  scrolling  on   a	per-plane   basis   with   nc-
       plane_set_scrolling.   Attempting  to print past	the end	of a line will
       stop at the plane boundary, and indicate	 an  error.   On  a  plane  10
       columns	wide  and  two	rows high, printing "0123456789" at the	origin
       should succeed, but printing "01234567890" will by default fail at  the
       eleventh	 character.   In either	case, the cursor will be left at loca-
       tion 0x10; it must be moved before further printing can take place.  If
       scrolling is enabled, the first row will	be  filled  with  01234546789,
       the  second row will have 0 written to its first	column,	and the	cursor
       will end	up at 1x1.  Note that it is still an error to manually attempt
       to move the cursor off-plane, or	to  specify  off-plane	output.	  Box-
       drawing	does not result	in scrolling; attempting to draw a 2x11	box on
       our 2x10	plane will result in an	error and no output.   When  scrolling
       is  enabled, and	output takes place while the cursor is past the	end of
       the last	row, the first row is discarded, all other rows	are moved  up,
       the last	row is cleared,	and output begins at the beginning of the last
       row.   This  does not take place	until output is	generated (i.e.	 it is
       possible	to fill	a plane	when scrolling is enabled).

       Creating	a plane	with the NCPLANE_OPTION_VSCROLL	flag is	equivalent  to
       immediately  calling  ncplane_set_scrolling on that plane with an argu-
       ment of true.

       By default, planes bound	to a scrolling plane will  scroll  along  with
       it, if they intersect the plane.	 This can be disabled by creating them
       with the	NCPLANE_OPTION_FIXED flag.

   Autogrow
       Normally,  once output reaches the right	boundary of a plane, it	is im-
       possible	to place more output unless the	cursor	is  first  moved.   If
       scrolling  is  enabled,	the cursor will	automatically move down	and to
       the left	in this	case, but upon reaching	the bottom right corner	of the
       plane, it is impossible to place	more output without a scrolling	event.
       If autogrow is in play, the plane will automatically be enlarged	to ac-
       commodate output.  If scrolling is disabled, growth takes place to  the
       right; it otherwise takes place at the bottom.  The plane only grows in
       one dimension.  Autogrow	cannot be enabled for the standard plane.

       Creating	a plane	with the NCPLANE_OPTION_AUTOGROW flag is equivalent to
       immediately calling ncplane_set_autogrow	on that	plane with an argument
       of true.

   Bitmaps
       ncplane_pixel_geom  retrieves  pixel geometry details.  pxy and pxx re-
       turn the	size of	the plane in pixels.  celldimy and celldimx return the
       size of a cell in pixels	(these	ought  be  the	same  across  planes).
       maxbmapy	 and  maxbmapx	describe  the largest bitmap which can be dis-
       played in the plane.  Any parameter (save n) may	be NULL.

       When a plane is blitted to using	ncvisual_blit  and  NCBLIT_PIXEL  (see
       notcurses_visual(3)),  it  ceases  to  accept  cell-based  output.  The
       sprixel will remain associated until a new sprixel is  blitted  to  the
       plane,  the  plane is resized, the plane	is erased, or the plane	is de-
       stroyed.	 The base cell of a sprixelated	plane has no  effect;  if  the
       sprixel	is not even multiples of the cell geometry, the	"excess	plane"
       is ignored during rendering.

RETURN VALUES
       ncplane_create and ncplane_dup return a new struct ncplane on  success,
       or NULL on failure.

       ncplane_userptr	returns	 the  configured user pointer for the ncplane,
       and cannot fail.

       ncplane_below returns the plane below the specified  ncplane.   If  the
       provided	 plane	is  the	bottommost plane, NULL is returned.  It	cannot
       fail.

       ncplane_set_scrolling returns true if scrolling was previously enabled,
       and false otherwise.

       ncplane_at_yx and ncplane_at_cursor return a heap-allocated copy	of the
       EGC at the relevant cell, or NULL if the	cell is	invalid.   The	caller
       should free this	result.	 ncplane_at_yx_cell and	ncplane_at_cursor_cell
       instead	load  these values into	an nccell, which is invalidated	if the
       associated plane	is destroyed.  The caller should release  this	nccell
       with nccell_release.

       ncplane_as_rgba returns a heap-allocated	array of uint32_t values, each
       representing a single RGBA pixel, or NULL on failure.

       ncplane_erase_region  returns  -1 if ystart or xstart are less than -1,
       or outside the plane.

       ncplane_cursor_move_yx returns -1 if the	coordinates are	beyond the di-
       mensions	of the specified plane (except for the special value -1).

       ncplane_cursor_move_rel returns -1 if the coordinates  are  beyond  the
       dimensions of the specified plane.

       ncplane_name returns a heap-allocated copy of the plane's name, or NULL
       if it has no name (or on	error).

       Functions returning int return 0	on success, and	non-zero on error.

       All other functions cannot fail (and return void).

NOTES
BUGS
       ncplane_at_yx  doesn't  yet  account  for  bitmap-based	graphics  (see
       notcurses_visual(3)).  Whatever glyph-based  contents  existed  on  the
       plane when the bitmap was blitted will continue to be returned.

       When the	alternate screen is not	used (see notcurses_init(3)), the con-
       tents  of the terminal at startup remain	present	until obliterated on a
       cell-by-cell basis.  ncplane_erase and ncplane_erase_region  cannot  be
       used  to	clear the terminal of startup content.	If you want the	screen
       cleared on startup, but do not want to use (or rely on)	the  alternate
       screen, use something like:

	      ncplane_set_base(notcurses_stdplane(nc), " ", 0, 0);
	      notcurses_render(nc);

       or simply:

	      notcurses_refresh(nc);

SEE ALSO
       notcurses(3),  notcurses_capabilities(3),  notcurses_cell(3),  notcurs-
       es_output(3), notcurses_pile(3),	notcurses_stdplane(3), notcurses_visu-
       al(3)

AUTHORS
       nick black <nickblack@linux.com>.

				    v3.0.8		    notcurses_plane(3)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=notcurses_plane&sektion=3&manpath=FreeBSD+Ports+14.3.quarterly>

home | help