clrpick.tcl –

Color selection dialog for platforms that do not support a

standard color selection dialog.

RCS: @(#) $Id: clrpick.tcl,v 1.20.2.2 2006/03/17 10:50:11 patthoyts Exp $

Copyright (c) 1996 Sun Microsystems, Inc.

See the file “license.terms” for information on usage and redistribution

of this file, and for a DISCLAIMER OF ALL WARRANTIES.

ToDo:

(1): Find out how many free colors are left in the colormap and

don’t allocate too many colors.

(2): Implement HSV color selection.

Make sure namespaces exist

namespace eval ::tk {}
namespace eval ::tk::dialog {}
namespace eval ::tk::dialog::color {
namespace import ::tk::msgcat::*
}

::tk::dialog::color:: –

Create a color dialog and let the user choose a color. This function

should not be called directly. It is called by the tk_chooseColor

function when a native color selector widget does not exist

proc ::tk::dialog::color:: {args} {
variable ::tk::Priv
set dataName __tk__color
upvar ::tk::dialog::color::dataName data set w .dataName

# The lines variables track the start and end indices of the line
# elements in the colorbar canvases.
set data(lines,red,start)   0
set data(lines,red,last)   -1
set data(lines,green,start) 0
set data(lines,green,last) -1
set data(lines,blue,start)  0
set data(lines,blue,last)  -1

# This is the actual number of lines that are drawn in each color strip.
# Note that the bars may be of any width.
# However, NUM_COLORBARS must be a number that evenly divides 256.
# Such as 256, 128, 64, etc.
set data(NUM_COLORBARS) 16

# BARS_WIDTH is the number of pixels wide the color bar portion of the
# canvas is. This number must be a multiple of NUM_COLORBARS
set data(BARS_WIDTH) 160

# PLGN_WIDTH is the number of pixels wide of the triangular selection
# polygon. This also results in the definition of the padding on the 
# left and right sides which is half of PLGN_WIDTH. Make this number even.
set data(PLGN_HEIGHT) 10

# PLGN_HEIGHT is the height of the selection polygon and the height of the 
# selection rectangle at the bottom of the color bar. No restrictions.
set data(PLGN_WIDTH) 10

Config $dataName $args
InitValues $dataName

set sc [winfo screen $data(-parent)]
set winExists [winfo exists $w]
if {!$winExists || $sc ne [winfo screen $w]} {
if {$winExists} {
    destroy $w
}
toplevel $w -class TkColorDialog -screen $sc
BuildDialog $w
}

# Dialog boxes should be transient with respect to their parent,
# so that they will always stay on top of their parent window.  However,
# some window managers will create the window as withdrawn if the parent
# window is withdrawn or iconified.  Combined with the grab we put on the
# window, this can hang the entire application.  Therefore we only make
# the dialog transient if the parent is viewable.

if {[winfo viewable [winfo toplevel $data(-parent)]] } {
wm transient $w $data(-parent)
}

# 5. Withdraw the window, then update all the geometry information
# so we know how big it wants to be, then center the window in the
# display and de-iconify it.

::tk::PlaceWindow $w widget $data(-parent)
wm title $w $data(-title)

# 6. Set a grab and claim the focus too.

::tk::SetFocusGrab $w $data(okBtn)

# 7. Wait for the user to respond, then restore the focus and
# return the index of the selected button.  Restore the focus
# before deleting the window, since otherwise the window manager
# may take the focus away so we can't redirect it.  Finally,
# restore any grab that was in effect.

vwait ::tk::Priv(selectColor)
::tk::RestoreFocusGrab $w $data(okBtn)
unset data

return $Priv(selectColor)

}

::tk::dialog::color::InitValues –

Get called during initialization or when user resets NUM_COLORBARS

proc ::tk::dialog::color::InitValues {dataName} {
upvar ::tk::dialog::color::$dataName data

# IntensityIncr is the difference in color intensity between a colorbar
# and its neighbors.
set data(intensityIncr) [expr {256 / $data(NUM_COLORBARS)}]

# ColorbarWidth is the width of each colorbar
set data(colorbarWidth) \
    [expr {$data(BARS_WIDTH) / $data(NUM_COLORBARS)}]

# Indent is the width of the space at the left and right side of the
# colorbar. It is always half the selector polygon width, because the
# polygon extends into the space.
set data(indent) [expr {$data(PLGN_WIDTH) / 2}]

set data(colorPad) 2
set data(selPad)   [expr {$data(PLGN_WIDTH) / 2}]

#
# minX is the x coordinate of the first colorbar
#
set data(minX) $data(indent)

#
# maxX is the x coordinate of the last colorbar
#
set data(maxX) [expr {$data(BARS_WIDTH) + $data(indent)-1}]

#
# canvasWidth is the width of the entire canvas, including the indents
#
set data(canvasWidth) [expr {$data(BARS_WIDTH) + $data(PLGN_WIDTH)}]

# Set the initial color, specified by -initialcolor, or the
# color chosen by the user the last time.
set data(selection) $data(-initialcolor)
set data(finalColor)  $data(-initialcolor)
set rgb [winfo rgb . $data(selection)]

set data(red,intensity)   [expr {[lindex $rgb 0]/0x100}]
set data(green,intensity) [expr {[lindex $rgb 1]/0x100}]
set data(blue,intensity)  [expr {[lindex $rgb 2]/0x100}]

}

::tk::dialog::color::Config –

Parses the command line arguments to tk_chooseColor

proc ::tk::dialog::color::Config {dataName argList} {
variable ::tk::Priv
upvar ::tk::dialog::color::$dataName data

# 1: the configuration specs
#
if {[info exists Priv(selectColor)] && $Priv(selectColor) ne ""} {
set defaultColor $Priv(selectColor)
} else {
set defaultColor [. cget -background]
}

set specs [list \
    [list -initialcolor "" "" $defaultColor] \
    [list -parent "" "" "."] \
    [list -title "" "" [mc "Color"]] \
    ]

# 2: parse the arguments
#
tclParseConfigSpec ::tk::dialog::color::$dataName $specs "" $argList

if {$data(-title) eq ""} {
set data(-title) " "
}
if {[catch {winfo rgb . $data(-initialcolor)} err]} {
error $err
}

if {![winfo exists $data(-parent)]} {
error "bad window path name \"$data(-parent)\""
}

}

::tk::dialog::color::BuildDialog –

Build the dialog.

proc ::tk::dialog::color::BuildDialog {w} {
upvar ::tk::dialog::color::[winfo name $w] data

# TopFrame contains the color strips and the color selection
#
set topFrame [frame $w.top -relief raised -bd 1]

# StripsFrame contains the colorstrips and the individual RGB entries
set stripsFrame [frame $topFrame.colorStrip]

set maxWidth [::tk::mcmaxamp &Red &Green &Blue]
set maxWidth [expr {$maxWidth<6?6:$maxWidth}]
set colorList [list \
    red		[mc "&Red"]	\
    green	[mc "&Green"]	\
    blue	[mc "&Blue"]	\
    ]
foreach {color l} $colorList {
# each f frame contains an [R|G|B] entry and the equiv. color strip.
set f [frame $stripsFrame.$color]

# The box frame contains the label and entry widget for an [R|G|B]
set box [frame $f.box]

bind [::tk::AmpWidget label $box.label -text $l: -width $maxWidth \
    -anchor ne] <<AltUnderlined>> [list focus $box.entry]

entry $box.entry -textvariable \
	::tk::dialog::color::[winfo name $w]($color,intensity) \
	-width 4
pack $box.label -side left -fill y -padx 2 -pady 3
pack $box.entry -side left -anchor n -pady 0
pack $box -side left -fill both

set height [expr \
    {[winfo reqheight $box.entry] - \
    2*([$box.entry cget -highlightthickness] + [$box.entry cget -bd])}]

canvas $f.color -height $height\
    -width $data(BARS_WIDTH) -relief sunken -bd 2
canvas $f.sel -height $data(PLGN_HEIGHT) \
    -width $data(canvasWidth) -highlightthickness 0
pack $f.color -expand yes -fill both
pack $f.sel -expand yes -fill both

pack $f -side top -fill x -padx 0 -pady 2

set data($color,entry) $box.entry
set data($color,col) $f.color
set data($color,sel) $f.sel

bind $data($color,col) <Configure> \
    [list tk::dialog::color::DrawColorScale $w $color 1]
bind $data($color,col) <Enter> \
    [list tk::dialog::color::EnterColorBar $w $color]
bind $data($color,col) <Leave> \
    [list tk::dialog::color::LeaveColorBar $w $color]

bind $data($color,sel) <Enter> \
    [list tk::dialog::color::EnterColorBar $w $color]
bind $data($color,sel) <Leave> \
    [list tk::dialog::color::LeaveColorBar $w $color]

bind $box.entry <Return> [list tk::dialog::color::HandleRGBEntry $w]
}

pack $stripsFrame -side left -fill both -padx 4 -pady 10

# The selFrame contains a frame that demonstrates the currently
# selected color
#
set selFrame [frame $topFrame.sel]
set lab [::tk::AmpWidget label $selFrame.lab -text [mc "&Selection:"] \
    -anchor sw]
set ent [entry $selFrame.ent \
-textvariable ::tk::dialog::color::[winfo name $w](selection) \
-width 16]
set f1  [frame $selFrame.f1 -relief sunken -bd 2]
set data(finalCanvas) [frame $f1.demo -bd 0 -width 100 -height 70]

pack $lab $ent -side top -fill x -padx 4 -pady 2
pack $f1 -expand yes -anchor nw -fill both -padx 6 -pady 10
pack $data(finalCanvas) -expand yes -fill both

bind $ent <Return> [list tk::dialog::color::HandleSelEntry $w]

pack $selFrame -side left -fill none -anchor nw
pack $topFrame -side top -expand yes -fill both -anchor nw

# the botFrame frame contains the buttons
#
set botFrame [frame $w.bot -relief raised -bd 1]

::tk::AmpWidget button $botFrame.ok     -text [mc "&OK"]		\
    -command [list tk::dialog::color::OkCmd $w]
::tk::AmpWidget button $botFrame.cancel -text [mc "&Cancel"]	\
    -command [list tk::dialog::color::CancelCmd $w]

set data(okBtn)      $botFrame.ok
set data(cancelBtn)  $botFrame.cancel

grid x $botFrame.ok x $botFrame.cancel x -sticky ew
grid configure $botFrame.ok $botFrame.cancel -padx 10 -pady 10
grid columnconfigure $botFrame {0 4} -weight 1 -uniform space
grid columnconfigure $botFrame {1 3} -weight 1 -uniform button
grid columnconfigure $botFrame 2 -weight 2 -uniform space
pack $botFrame -side bottom -fill x


# Accelerator bindings
bind $lab <<AltUnderlined>> [list focus $ent]
bind $w <KeyPress-Escape> [list tk::ButtonInvoke $data(cancelBtn)]
bind $w <Alt-Key> [list tk::AltKeyInDialog $w %A]

wm protocol $w WM_DELETE_WINDOW [list tk::dialog::color::CancelCmd $w]

}

::tk::dialog::color::SetRGBValue –

Sets the current selection of the dialog box

proc ::tk::dialog::color::SetRGBValue {w color} {
upvar ::tk::dialog::color::[winfo name $w] data

set data(red,intensity)   [lindex $color 0]
set data(green,intensity) [lindex $color 1]
set data(blue,intensity)  [lindex $color 2]

RedrawColorBars $w all

# Now compute the new x value of each colorbars pointer polygon
foreach color [list red green blue ] {
set x [RgbToX $w $data($color,intensity)]
MoveSelector $w $data($color,sel) $color $x 0
}

}

::tk::dialog::color::XToRgb –

Converts a screen coordinate to intensity

proc ::tk::dialog::color::XToRgb {w x} {
upvar ::tk::dialog::color::[winfo name $w] data

set x [expr {($x * $data(intensityIncr))/ $data(colorbarWidth)}]
if {$x > 255} { set x 255 }
return $x

}

::tk::dialog::color::RgbToX

Converts an intensity to screen coordinate.

proc ::tk::dialog::color::RgbToX {w color} {
upvar ::tk::dialog::color::[winfo name $w] data

return [expr {($color * $data(colorbarWidth)/ $data(intensityIncr))}]

}

::tk::dialog::color::DrawColorScale –

Draw color scale is called whenever the size of one of the color

scale canvases is changed.

proc ::tk::dialog::color::DrawColorScale {w c {create 0}} {
upvar ::tk::dialog::color::[winfo name $w] data

# col: color bar canvas
# sel: selector canvas
set col $data($c,col)
set sel $data($c,sel)

# First handle the case that we are creating everything for the first time.
if {$create} {
# First remove all the lines that already exist.
if { $data(lines,$c,last) > $data(lines,$c,start)} {
    for {set i $data(lines,$c,start)} \
	{$i <= $data(lines,$c,last)} { incr i} {
	$sel delete $i
    }
}
# Delete the selector if it exists
if {[info exists data($c,index)]} {
    $sel delete $data($c,index)
}

# Draw the selection polygons
CreateSelector $w $sel $c
$sel bind $data($c,index) <ButtonPress-1> \
	[list tk::dialog::color::StartMove $w $sel $c %x $data(selPad) 1]
$sel bind $data($c,index) <B1-Motion> \
	[list tk::dialog::color::MoveSelector $w $sel $c %x $data(selPad)]
$sel bind $data($c,index) <ButtonRelease-1> \
	[list tk::dialog::color::ReleaseMouse $w $sel $c %x $data(selPad)]

set height [winfo height $col]
# Create an invisible region under the colorstrip to catch mouse clicks
# that aren't on the selector.
set data($c,clickRegion) [$sel create rectangle 0 0 \
	$data(canvasWidth) $height -fill {} -outline {}]

bind $col <ButtonPress-1> \
	[list tk::dialog::color::StartMove $w $sel $c %x $data(colorPad)]
bind $col <B1-Motion> \
	[list tk::dialog::color::MoveSelector $w $sel $c %x $data(colorPad)]
bind $col <ButtonRelease-1> \
	[list tk::dialog::color::ReleaseMouse $w $sel $c %x $data(colorPad)]

$sel bind $data($c,clickRegion) <ButtonPress-1> \
	[list tk::dialog::color::StartMove $w $sel $c %x $data(selPad)]
$sel bind $data($c,clickRegion) <B1-Motion> \
	[list tk::dialog::color::MoveSelector $w $sel $c %x $data(selPad)]
$sel bind $data($c,clickRegion) <ButtonRelease-1> \
	[list tk::dialog::color::ReleaseMouse $w $sel $c %x $data(selPad)]
} else {
# l is the canvas index of the first colorbar.
set l $data(lines,$c,start)
}

# Draw the color bars.
set highlightW [expr {[$col cget -highlightthickness] + [$col cget -bd]}]
for {set i 0} { $i < $data(NUM_COLORBARS)} { incr i} {
set intensity [expr {$i * $data(intensityIncr)}]
set startx [expr {$i * $data(colorbarWidth) + $highlightW}]
if {$c eq "red"} {
    set color [format "#%02x%02x%02x" \
		   $intensity \
		   $data(green,intensity) \
		   $data(blue,intensity)]
} elseif {$c eq "green"} {
    set color [format "#%02x%02x%02x" \
		   $data(red,intensity) \
		   $intensity \
		   $data(blue,intensity)]
} else {
    set color [format "#%02x%02x%02x" \
		   $data(red,intensity) \
		   $data(green,intensity) \
		   $intensity]
}

if {$create} {
    set index [$col create rect $startx $highlightW \
	    [expr {$startx +$data(colorbarWidth)}] \
	    [expr {[winfo height $col] + $highlightW}]\
        -fill $color -outline $color]
} else {
    $col itemconfigure $l -fill $color -outline $color
    incr l
}
}
$sel raise $data($c,index)

if {$create} {
set data(lines,$c,last) $index
set data(lines,$c,start) [expr {$index - $data(NUM_COLORBARS) + 1}]
}

RedrawFinalColor $w

}

::tk::dialog::color::CreateSelector –

Creates and draws the selector polygon at the position

data(c,intensity).

proc ::tk::dialog::color::CreateSelector {w sel c } {
upvar ::tk::dialog::color::[winfo name w] data set data(c,index) [$sel create polygon
0 $data(PLGN_HEIGHT)
$data(PLGN_WIDTH) $data(PLGN_HEIGHT)
data(indent) 0] set data(c,x) [RgbToX $w data(c,intensity)]
$sel move data(c,index) data(c,x) 0
}

::tk::dialog::color::RedrawFinalColor

Combines the intensities of the three colors into the final color

proc ::tk::dialog::color::RedrawFinalColor {w} {
upvar ::tk::dialog::color::[winfo name $w] data

set color [format "#%02x%02x%02x" $data(red,intensity) \
$data(green,intensity) $data(blue,intensity)]

$data(finalCanvas) configure -bg $color
set data(finalColor) $color
set data(selection) $color
set data(finalRGB) [list \
    $data(red,intensity) \
    $data(green,intensity) \
    $data(blue,intensity)]

}

::tk::dialog::color::RedrawColorBars –

Only redraws the colors on the color strips that were not manipulated.

Params: color of colorstrip that changed. If color is not [red|green|blue]

Then all colorstrips will be updated

proc ::tk::dialog::color::RedrawColorBars {w colorChanged} {
upvar ::tk::dialog::color::[winfo name $w] data

switch $colorChanged {
red { 
    DrawColorScale $w green
    DrawColorScale $w blue
}
green {
    DrawColorScale $w red
    DrawColorScale $w blue
}
blue {
    DrawColorScale $w red
    DrawColorScale $w green
}
default {
    DrawColorScale $w red
    DrawColorScale $w green
    DrawColorScale $w blue
}
}
RedrawFinalColor $w

}

#–––––––––––––––––––––––––––––––––––

Event handlers

#–––––––––––––––––––––––––––––––––––

::tk::dialog::color::StartMove –

Handles a mousedown button event over the selector polygon.

Adds the bindings for moving the mouse while the button is

pressed. Sets the binding for the button-release event.

Params: sel is the selector canvas window, color is the color of the strip.

proc ::tk::dialog::color::StartMove {w sel color x delta {dontMove 0}} {
upvar ::tk::dialog::color::[winfo name $w] data

if {!$dontMove} {
MoveSelector $w $sel $color $x $delta
}

}

::tk::dialog::color::MoveSelector –

Moves the polygon selector so that its middle point has the same

x value as the specified x. If x is outside the bounds [0,255],

the selector is set to the closest endpoint.

Params: sel is the selector canvas, c is [red|green|blue]

x is a x-coordinate.

proc ::tk::dialog::color::MoveSelector {w sel color x delta} {
upvar ::tk::dialog::color::[winfo name $w] data

incr x -$delta

if { $x < 0 } {
set x 0
} elseif { $x > $data(BARS_WIDTH)} {
set x $data(BARS_WIDTH)
}
set diff [expr {$x - $data($color,x)}]
$sel move $data($color,index) $diff 0
set data($color,x) [expr {$data($color,x) + $diff}]

# Return the x value that it was actually set at
return $x

}

::tk::dialog::color::ReleaseMouse

Removes mouse tracking bindings, updates the colorbars.

Params: sel is the selector canvas, color is the color of the strip,

x is the x-coord of the mouse.

proc ::tk::dialog::color::ReleaseMouse {w sel color x delta} {
upvar ::tk::dialog::color::[winfo name $w] data

set x [MoveSelector $w $sel $color $x $delta]

# Determine exactly what color we are looking at.
set data($color,intensity) [XToRgb $w $x]

RedrawColorBars $w $color

}

::tk::dialog::color::ResizeColorbars –

Completely redraws the colorbars, including resizing the

colorstrips

proc ::tk::dialog::color::ResizeColorBars {w} {
upvar ::tk::dialog::color::[winfo name $w] data

if { ($data(BARS_WIDTH) < $data(NUM_COLORBARS)) || 
 (($data(BARS_WIDTH) % $data(NUM_COLORBARS)) != 0)} {
set data(BARS_WIDTH) $data(NUM_COLORBARS)
}
InitValues [winfo name $w]
foreach color [list red green blue ] {
$data($color,col) configure -width $data(canvasWidth)
DrawColorScale $w $color 1
}

}

::tk::dialog::color::HandleSelEntry –

Handles the return keypress event in the “Selection:” entry

proc ::tk::dialog::color::HandleSelEntry {w} {
upvar ::tk::dialog::color::[winfo name $w] data

set text [string trim $data(selection)]
# Check to make sure that the color is valid
if {[catch {set color [winfo rgb . $text]} ]} {
set data(selection) $data(finalColor)
return
}

set R [expr {[lindex $color 0]/0x100}]
set G [expr {[lindex $color 1]/0x100}]
set B [expr {[lindex $color 2]/0x100}]

SetRGBValue $w "$R $G $B"
set data(selection) $text

}

::tk::dialog::color::HandleRGBEntry –

Handles the return keypress event in the R, G or B entry

proc ::tk::dialog::color::HandleRGBEntry {w} {
upvar ::tk::dialog::color::[winfo name $w] data

foreach c [list red green blue] {
if {[catch {
    set data($c,intensity) [expr {int($data($c,intensity))}]
}]} {
    set data($c,intensity) 0
}

if {$data($c,intensity) < 0} {
    set data($c,intensity) 0
}
if {$data($c,intensity) > 255} {
    set data($c,intensity) 255
}
}

SetRGBValue $w "$data(red,intensity) \
$data(green,intensity) $data(blue,intensity)"

}

mouse cursor enters a color bar

proc ::tk::dialog::color::EnterColorBar {w color} {
upvar ::tk::dialog::color::[winfo name $w] data

$data($color,sel) itemconfigure $data($color,index) -fill red

}

mouse leaves enters a color bar

proc ::tk::dialog::color::LeaveColorBar {w color} {
upvar ::tk::dialog::color::[winfo name $w] data

$data($color,sel) itemconfigure $data($color,index) -fill black

}

user hits OK button

proc ::tk::dialog::color::OkCmd {w} {
variable ::tk::Priv
upvar ::tk::dialog::color::[winfo name $w] data

set Priv(selectColor) $data(finalColor)

}

user hits Cancel button

proc ::tk::dialog::color::CancelCmd {w} {
variable ::tk::Priv
set Priv(selectColor) “”
}