libtk/library/palette.tcl

# palette.tcl --
#
# This file contains procedures that change the color palette used
# by Tk.
#
# SCCS: @(#) palette.tcl 1.4 96/12/04 10:00:17
#
# Copyright (c) 1995 Sun Microsystems, Inc.
#
# See the file "license.terms" for information on usage and redistribution
# of this file, and for a DISCLAIMER OF ALL WARRANTIES.
#

# tk_setPalette --
# Changes the default color scheme for a Tk application by setting
# default colors in the option database and by modifying all of the
# color options for existing widgets that have the default value.
#
# Arguments:
# The arguments consist of either a single color name, which
# will be used as the new background color (all other colors will
# be computed from this) or an even number of values consisting of
# option names and values.  The name for an option is the one used
# for the option database, such as activeForeground, not -activeforeground.

proc tk_setPalette args {
    global tkPalette

    # Create an array that has the complete new palette.  If some colors
    # aren't specified, compute them from other colors that are specified.

    if {[llength $args] == 1} {
    set new(background) [lindex $args 0]
    } else {
    array set new $args
    }
    if ![info exists new(background)] {
    error "must specify a background color"
    }
    if ![info exists new(foreground)] {
    set new(foreground) black
    }
    set bg [winfo rgb . $new(background)]
    set fg [winfo rgb . $new(foreground)]
    set darkerBg [format #%02x%02x%02x [expr (9*[lindex $bg 0])/2560] \
        [expr (9*[lindex $bg 1])/2560] [expr (9*[lindex $bg 2])/2560]]
    foreach i {activeForeground insertBackground selectForeground \
        highlightColor} {
    if ![info exists new($i)] {
        set new($i) $new(foreground)
    }
    }
    if ![info exists new(disabledForeground)] {
    set new(disabledForeground) [format #%02x%02x%02x \
        [expr (3*[lindex $bg 0] + [lindex $fg 0])/1024] \
        [expr (3*[lindex $bg 1] + [lindex $fg 1])/1024] \
        [expr (3*[lindex $bg 2] + [lindex $fg 2])/1024]]
    }
    if ![info exists new(highlightBackground)] {
    set new(highlightBackground) $new(background)
    }
    if ![info exists new(activeBackground)] {
    # Pick a default active background that islighter than the
    # normal background.  To do this, round each color component
    # up by 15% or 1/3 of the way to full white, whichever is
    # greater.

    foreach i {0 1 2} {
        set light($i) [expr [lindex $bg $i]/256]
        set inc1 [expr ($light($i)*15)/100]
        set inc2 [expr (255-$light($i))/3]
        if {$inc1 > $inc2} {
        incr light($i) $inc1
        } else {
        incr light($i) $inc2
        }
        if {$light($i) > 255} {
        set light($i) 255
        }
    }
    set new(activeBackground) [format #%02x%02x%02x $light(0) \
        $light(1) $light(2)]
    }
    if ![info exists new(selectBackground)] {
    set new(selectBackground) $darkerBg
    }
    if ![info exists new(troughColor)] {
    set new(troughColor) $darkerBg
    }
    if ![info exists new(selectColor)] {
    set new(selectColor) #b03060
    }

    # Walk the widget hierarchy, recoloring all existing windows.
    # The option database must be set according to what we do here,
    # but it breaks things if we set things in the database while
    # we are changing colors...so, tkRecolorTree now returns the
    # option database changes that need to be made, and they
    # need to be evalled here to take effect.

    eval [tkRecolorTree . new]

    # Save the options in the global variable tkPalette, for use the
    # next time we change the options.

    array set tkPalette [array get new]
}

# tkRecolorTree --
# This procedure changes the colors in a window and all of its
# descendants, according to information provided by the colors
# argument. This looks at the defaults provided by the option
# database, if it exists, and if not, then it looks at the default
# value of the widget itself.
#
# Arguments:
# w -           The name of a window.  This window and all its
#           descendants are recolored.
# colors -      The name of an array variable in the caller,
#           which contains color information.  Each element
#           is named after a widget configuration option, and
#           each value is the value for that option.

proc tkRecolorTree {w colors} {
    global tkPalette
    upvar $colors c
    set result {}
    foreach dbOption [array names c] {
    set option -[string tolower $dbOption]
    if {![catch {$w config $option} value]} {
        # if the option database has a preference for this
        # dbOption, then use it, otherwise use the defaults
        # for the widget.
        set defaultcolor [option get $w $dbOption widgetDefault]
        if {[string match {} $defaultcolor]} {
        set defaultcolor [winfo rgb . [lindex $value 3]]
        } else {
        set defaultcolor [winfo rgb . $defaultcolor]
        }
        set chosencolor [winfo rgb . [lindex $value 4]]
        if {[string match $defaultcolor $chosencolor]} {
        # Change the option database so that future windows will get the
        # same colors.

        append result ";\noption add *[winfo class $w].$dbOption $c($dbOption)"
        $w configure $option $c($dbOption)
        }
    }
    }
    foreach child [winfo children $w] {
    append result ";\n[tkRecolorTree $child c]"
    }
    return $result
}

# tkDarken --
# Given a color name, computes a new color value that darkens (or
# brightens) the given color by a given percent.
#
# Arguments:
# color -   Name of starting color.
# perecent -    Integer telling how much to brighten or darken as a
#       percent: 50 means darken by 50%, 110 means brighten
#       by 10%.

proc tkDarken {color percent} {
    set l [winfo rgb . $color]
    set red [expr [lindex $l 0]/256]
    set green [expr [lindex $l 1]/256]
    set blue [expr [lindex $l 2]/256]
    set red [expr ($red*$percent)/100]
    if {$red > 255} {
    set red 255
    }
    set green [expr ($green*$percent)/100]
    if {$green > 255} {
    set green 255
    }
    set blue [expr ($blue*$percent)/100]
    if {$blue > 255} {
    set blue 255
    }
    format #%02x%02x%02x $red $green $blue
}

# tk_bisque --
# Reset the Tk color palette to the old "bisque" colors.
#
# Arguments:
# None.

proc tk_bisque {} {
    tk_setPalette activeBackground #e6ceb1 activeForeground black \
        background #ffe4c4 disabledForeground #b0b0b0 foreground black \
        highlightBackground #ffe4c4 highlightColor black \
        insertBackground black selectColor #b03060 \
        selectBackground #e6ceb1 selectForeground black \
        troughColor #cdb79e
}