notcurses_capabilities(3)

nick black

v2.4.9

NAME

notcurses_capabilities - runtime capability detection

SYNOPSIS

#include <notcurses/notcurses.h>

const char* notcurses_detected_terminal(const struct notcurses* nc);

unsigned notcurses_supported_styles(const struct notcurses* nc);

unsigned notcurses_palette_size(const struct notcurses* nc);

bool notcurses_cantruecolor(const struct notcurses* nc);

bool notcurses_canfade(const struct notcurses* nc);

bool notcurses_canchangecolor(const struct notcurses* nc);

bool notcurses_canopen_images(const struct notcurses* nc);

bool notcurses_canopen_videos(const struct notcurses* nc);

bool notcurses_canutf8(const struct notcurses* nc);

bool notcurses_canhalfblock(const struct notcurses* nc);

bool notcurses_canquadrant(const struct notcurses* nc);

bool notcurses_cansextant(const struct notcurses* nc);

bool notcurses_canbraille(const struct notcurses* nc);

bool notcurses_canpixel(const struct notcurses* nc);

typedef enum {
  NCPIXEL_NONE = 0,
  NCPIXEL_SIXEL,           // sixel
  NCPIXEL_LINUXFB,         // linux framebuffer
  NCPIXEL_ITERM2,          // iTerm2
  NCPIXEL_KITTY_STATIC,    // kitty pre-0.20.0
  NCPIXEL_KITTY_ANIMATED,  // kitty pre-0.22.0
  NCPIXEL_KITTY_SELFREF,   // kitty 0.22.0+, wezterm
} ncpixelimpl_e;

ncpixelimpl_e notcurses_check_pixel_support(struct notcurses* nc);

DESCRIPTION

notcurses_detected_terminal returns a free-form string describing the detected terminal. Terminal detection takes into account any specified terminal database (see notcurses_init(3)), the TERM, TERM_PROGRAM, and TERM_PROGRAM_VERSION environment variables, the response to a XTGETTCAP[TN] Device Control String, the response to Primary, Secondary, and Tertiary Send Device Attributes control sequences, and the phase of the moon. You should not build logic around this response; all relevant properties of the terminal ought be abstracted by Notcurses. This is only made available for diagnostics.

notcurses_supported_styles returns a bitmask representing those styles for which the terminal advertises support.

notcurses_palette_size returns the size of the terminal's palette, used for palette-indexed color. It will always return at least 1. This is independent of RGB TrueColor support. No terminal is know to support more than 256-indexed color.

notcurses_cantruecolor returns true if the terminal advertises support for RGB TrueColor. Note that the RGB APIs of Notcurses can be used even in the absence of terminal RGB support (Notcurses will map the RGB values to the palette).

notcurses_canfade returns true if Notcurses has a means by which it can effect fades.

notcurses_canchangecolor returns true if the terminal advertises support for changing its palette entries.

notcurses_canopen_images returns true if Notcurses was built with multimedia support.

notcurses_canopen_video returns true if Notcurses was built with multimedia support capable of decoding videos.

notcurses_canutf8 returns true if the configured locale uses UTF-8 encoding, and the locale was successfully loaded.

notcurses_cansextant returns true if the heuristics suggest that the terminal can properly render Unicode 13 sextants. Likewise, notcurses_canquadrant and notcurses_canhalfblock return true if the heuristics suggest that the terminal can properly render Unicode quadrants and halfblocks, respectively. notcurses_canbraille returns true if Unicode Braille is expected to work on the terminal. None of these functions return true unless UTF-8 encoding is in use.

notcurses_check_pixel_support returns a non-zero pixel implementation if bitmap support (via any mechanism) has been detected, and otherwise 0 (NCPIXEL_NONE). notcurses_canpixel folds this down to a boolean.

NOTES

Some terminals advertise support for TrueColor, but then downsample or otherwise degrade the provided RGB. In this case notcurses_cantruecolor will return true, but the full spectrum will not be available.

SEE ALSO

notcurses(3), notcurses_init(3), notcurses_visual(3), utf8(7)