X-Git-Url: https://ncurses.scripts.mit.edu/?a=blobdiff_plain;f=doc%2Fhtml%2Fman%2Fcurs_color.3x.html;h=e693b553442454c4c831ded10ca4a0f577b6471d;hb=d1a029866f6d84087781eaa81de19949d8533426;hp=aae55777af4e6a20f955456cbe4f5c7c6b9f6500;hpb=7884aa084f9440fd964f14fe31853a5f85db5104;p=ncurses.git diff --git a/doc/html/man/curs_color.3x.html b/doc/html/man/curs_color.3x.html index aae55777..e693b553 100644 --- a/doc/html/man/curs_color.3x.html +++ b/doc/html/man/curs_color.3x.html @@ -1,6 +1,6 @@ - -curs_color 3x +curs_color 3x 2023-07-01 ncurses 6.4 Library calls - + -

curs_color 3x

+

curs_color 3x 2023-07-01 ncurses 6.4 Library calls

-curs_color(3x)                                                  curs_color(3x)
+curs_color(3x)                   Library calls                  curs_color(3x)
 
 
 
@@ -135,8 +135,8 @@
 
        o   If the parameter passed to waddch is not blank, or it does not  use
            the  special  color  pair 0, curses prefers the color pair from the
-           parameter, if it is nonzero.  Otherwise, it tries  the  window  at-
-           tribute next, and finally the background character.
+           parameter, if it is nonzero.  Otherwise, it tries the window attri-
+           bute next, and finally the background character.
 
        Some  curses  functions such as wprintw call waddch.  Those do not com-
        bine its parameter with a color pair.  Consequently those calls use on-
@@ -439,7 +439,59 @@
        o   Color RGB values are not settable.
 
 
+

HISTORY

+       SVr3.2 introduced color support to curses in 1987.
+
+       SVr4 made internal changes, e.g., moving  the  storage  for  the  color
+       state  from  SP (the SCREEN structure) to cur_term (the TERMINAL struc-
+       ture), but provided the same set of library functions.
+
+       SVr4 curses limits the number of color pairs  to  64,  reserving  color
+       pair  zero  (0)  as the terminal's initial uncolored state.  This limit
+       arises because the color pair information is a bitfield in  the  chtype
+       data type (denoted by A_COLOR).
+
+       Other implementations of curses had different limits:
+
+       o   PCCurses (1987-1990) provided for only eight (8) colors.
+
+       o   PDCurses  (1992-present)  inherited the 8-color limitation from PC-
+           Curses, but changed this to 256 in version 2.5 (2001),  along  with
+           changing chtype from 16-bits to 32-bits.
+
+       o   X/Open Curses (1992-present) added a new structure cchar_t to store
+           the character, attributes and color-pair values, allowing increased
+           range  of  color-pairs.   Both  color-pairs and color-values used a
+           signed short, limiting values to 15 bits.
+
+       o   ncurses (1992-present) uses eight bits for A_COLOR in  chtype  val-
+           ues.
+
+           Version  5.3  provided  a wide-character interface (2002), but left
+           color-pairs as part of the attributes-field.
+
+           Since version 6 (2015), ncurses uses a separate int for color-pairs
+           in the cchar_t values.  When those color-pair values fit in 8 bits,
+           ncurses allows color-pairs to be manipulated via the functions  us-
+           ing chtype values.
+
+       o   NetBSD  curses  used  6 bits from 2000 (when colors were first sup-
+           ported) until 2004.  At that point, NetBSD changed to use 10  bits.
+           As of 2021, that size is unchanged.  Like ncurses before version 6,
+           the NetBSD color-pair information is stored in the attributes field
+           of  cchar_t,  limiting the number of color-pairs by the size of the
+           bitfield.
+
+

PORTABILITY

+
+

Extensions

+       The functions marked as extensions were designed for  ncurses(3x),  and
+       are not found in SVr4 curses, 4.4BSD curses, or any other previous ver-
+       sion of curses.
+
+
+

Standards

        This implementation satisfies XSI Curses's minimum maximums for  COLORS
        and COLOR_PAIRS.
 
@@ -472,7 +524,7 @@
 
 
 
-                                                                curs_color(3x)
+ncurses 6.4                       2023-07-01                    curs_color(3x)