notcurses_palette(3)

nick black

v1.6.1

NAME

notcurses_palette - operations on notcurses palettes

SYNOPSIS

#include <notcurses/notcurses.h>

typedef struct palette256 {
  // We store the RGB values as a regular ol' channel
  uint32_t chans[256];
} palette256;

bool notcurses_cantruecolor(const struct notcurses* nc);

palette256* palette256_new(struct notcurses* nc);

int palette256_use(struct notcurses* nc, const palette256* p);

int palette256_set_rgb(palette256* p, int idx, int r, int g, int b);

int palette256_set(palette256* p, int idx, unsigned rgb);

int palette256_get_rgb(const palette256* p, int idx, int* restrict r, int* restrict g, int* restrict b);

void palette256_free(palette256* p);

bool notcurses_canchangecolors(const struct notcurses* nc);

DESCRIPTION

Some terminals only support 256 colors, but allow the full palette to be specified with arbitrary RGB colors. In all cases, it’s more performant to use indexed colors, since it’s much less data to write to the terminal. If you can limit yourself to 256 colors, that’s probably for the best.

In addition, palette-based color allows for very fast color cycling effects, since a single command can affect many cells on the screen.

RETURN VALUES

Functions returning int return -1 on failure, or 0 on success. Failure is always due to invalid inputs. Functions returning bool are predicates, and return the requested value. Functions returning unsigned forms return the input, modified as requested.

SEE ALSO

notcurses(3), notcurses_cell(3), notcurses_channels(3), notcurses_output(3), notcurses_plane(3)