X-Git-Url: http://ncurses.scripts.mit.edu/?a=blobdiff_plain;f=doc%2Fhtml%2Fman%2Fnew_pair.3x.html;h=ce4adc314495e6b68856dae6bc5aa0c30b36f78d;hb=0eedaa5673ff8181abe51e3a6fadca3820f90c46;hp=bc11784acc1d0b8c221d69f22ab647c94c858e11;hpb=06078d3fa68db669ed37178c01873546b4b28745;p=ncurses.git diff --git a/doc/html/man/new_pair.3x.html b/doc/html/man/new_pair.3x.html index bc11784a..ce4adc31 100644 --- a/doc/html/man/new_pair.3x.html +++ b/doc/html/man/new_pair.3x.html @@ -1,6 +1,7 @@ -
- --new_pair(3x) new_pair(3x) +new_pair(3x) Library calls new_pair(3x)
- alloc_pair, find_pair, free_pair - new curses color-pair functions + alloc_pair, find_pair, free_pair - dynamically allocate curses color + pairs
#include <curses.h> - int alloc_pair(int fg, int bg); - int find_pair(int fg, int bg); - int free_pair(int pair); + int alloc_pair(int fg, int bg); + int find_pair(int fg, int bg); + int free_pair(int pair);
- These functions are an extension to the curses library. They permit an - application to dynamically allocate a color pair using the fore- - ground/background colors rather than assign a fixed color pair number, - and return an unused pair to the pool. + These functions are an extension to the curses library. They permit an + application to dynamically allocate a color pair using the + foreground/background colors rather than assign a fixed color pair + number, and return an unused pair to the pool. - The number of colors may be related to the number of possible color + The number of colors may be related to the number of possible color pairs for a given terminal, or it may not: - o While almost all terminals allow setting the color attributes inde- - pendently, it is unlikely that your terminal allows you to modify - the attributes of a given character cell without rewriting it. - That is, the foreground and background colors are applied as a + o While almost all terminals allow setting the color attributes + independently, it is unlikely that your terminal allows you to + modify the attributes of a given character cell without rewriting + it. That is, the foreground and background colors are applied as a pair. - o Color pairs are the curses library's way of managing a color pal- - ette on a terminal. If the library does not keep track of the com- - binations of colors which are displayed, it will be inefficient. + o Color pairs are the curses library's way of managing a color + palette on a terminal. If the library does not keep track of the + combinations of colors which are displayed, it will be inefficient. - o For simple terminal emulators with only a few dozen color combina- - tions, it is convenient to use the maximum number of combinations - as the limit on color pairs: + o For simple terminal emulators with only a few dozen color + combinations, it is convenient to use the maximum number of + combinations as the limit on color pairs: COLORS * COLORS - o Terminals which support default colors distinct from "ANSI colors" + o Terminals which support default colors distinct from "ANSI colors" add to the possible combinations, producing this total: ( COLORS + 1 ) * ( COLORS + 1 ) @@ -91,44 +93,44 @@ o An application might use up to a few dozen color pairs to implement a predefined color scheme. - Beyond that lies in the realm of programs using the foreground and - background colors for "ASCII art" (or some other non-textual appli- - cation). + Beyond that lies in the realm of programs using the foreground and + background colors for "ASCII art" (or some other non-textual + application). Also beyond those few dozen pairs, the required size for a table to - represent the combinations grows rapidly with an increasing number + represent the combinations grows rapidly with an increasing number of colors. - These functions allow a developer to let the screen library manage + These functions allow a developer to let the screen library manage color pairs.
- The alloc_pair function accepts parameters for foreground and back- - ground color, and checks if that color combination is already associ- - ated with a color pair. + The alloc_pair function accepts parameters for foreground and + background color, and checks if that color combination is already + associated with a color pair. - o If the combination already exists, alloc_pair returns the existing + o If the combination already exists, alloc_pair returns the existing pair. o If the combination does not exist, alloc_pair allocates a new color pair and returns that. - o If the table fills up, alloc_pair discards the least-recently allo- - cated entry using free_pair and allocates a new color pair. + o If the table fills up, alloc_pair discards the least-recently + allocated entry using free_pair and allocates a new color pair. - All of the color pairs are allocated from a table of possible color - pairs. The size of the table is determined by the terminfo pairs capa- - bility. The table is shared with init_pair; in fact alloc_pair calls - init_pair after updating the ncurses library's fast index to the colors - versus color pairs. + All of the color pairs are allocated from a table of possible color + pairs. The size of the table is determined by the terminfo pairs + capability. The table is shared with init_pair; in fact alloc_pair + calls init_pair after updating the ncurses library's fast index to the + colors versus color pairs.
The find_pair function accepts parameters for foreground and background - color, and checks if that color combination is already associated with - a color pair, returning the pair number if it has been allocated. Oth- - erwise it returns -1. + color, and checks if that color combination is already associated with + a color pair, returning the pair number if it has been allocated. + Otherwise it returns -1.
@@ -136,34 +138,34 @@
- The alloc_pair function returns a color pair number in the range 1 - through COLOR_PAIRS-1, unless it encounters an error updating its fast - index to the color pair values, preventing it from allocating a color + The alloc_pair function returns a color pair number in the range 1 + through COLOR_PAIRS-1, unless it encounters an error updating its fast + index to the color pair values, preventing it from allocating a color pair. In that case, it returns -1. - The find_pair function returns a color pair number if the given color + The find_pair function returns a color pair number if the given color combination has been associated with a color pair, or -1 if not. - Likewise, free_pair returns OK unless it encounters an error updating + Likewise, free_pair returns OK unless it encounters an error updating the fast index or if no such color pair is in use.
- These routines are specific to ncurses. They were not supported on + These routines are specific to ncurses. They were not supported on Version 7, BSD or System V implementations. It is recommended that any - code depending on them be conditioned using NCURSES_VERSION. + code depending on them be conditioned using NCURSES_VERSION.
- init_pair(3x). + curs_color(3x)
- Thomas Dickey. + Thomas Dickey - new_pair(3x) +ncurses 6.4 2023-09-23 new_pair(3x)