notcurses_lines(3)

🌸 notcurses_lines(3): operations on lines and boxes 🌸

okay bestie, welcome to the notcurses_lines(3) manual 💅 this one is literally all about lines and boxes, no cap. it’s giving terminal arts-and-crafts, and we’re obsessed 🎀

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✨ NAME ✨

notcurses_lines — operations on lines and boxes

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🎀 SYNOPSIS 🎀

okay so first you include the header, then you get the whole cast of functions and defines exactly like this 👇

#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, nccell* 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);

that’s the whole lineup, no cuts, periodt ✨

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💖 DESCRIPTION 💖

• ncplane_polyfill_yx — starts at the specified y and x (provide -1 to use the cursor’s position in the relevant 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 vertical 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 💀

yes bestie, the DESCRIPTION says ncplane_gradient2x1 while the SYNOPSIS says ncplane_highgradient2x1 — I’m keeping both exactly as the page gives them, no edits from me 💅

• 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 🦋

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🦋 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 🙈

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🌈 SEE ALSO 🌈

• notcurses(3)
• notcurses_cell(3)
• notcurses_plane(3)

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👑 AUTHORS 👑

nick black nickblack@linux.com — the icon behind the lines and boxes 👑

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💖 bye bestie — this was notcurses_lines(3), version v3.0.17 💖