Marco Maggi The analog widgets are now (Aug 10, 2003) a package [L1 ].
A tachometer-like widget: type 1
A needlemeter widget: type 1 (an error in the title... RS fixed it)
A voltmeter-like widget: type 1
Here is a test script for the 3D circle border. See also: drawing gradients on a canvas, making color gradients and Gradients Color Transitions.
GPS This is cool! Thanks for sharing it. :)
package require Tcl 8
package require Tk 8
proc main { argc argv } {
global forever
wm withdraw .
wm title . "A shadowed 3D circle"
wm geometry . +10+10
canvas .c -background blue -width 400 -height 400
grid .c -sticky news
set num 10
set xcentre 200
set ycentre 200
for {set i 0} {$i < $num} {incr i} {
set radius [expr {20.0*$i}]
set orient [expr {360.0/$num*$i}]
set x1 [expr {$xcentre-$radius}]
set y1 [expr {$ycentre-$radius}]
set x2 [expr {$xcentre+$radius}]
set y2 [expr {$ycentre+$radius}]
shadowcircle .c $x1 $y1 $x2 $y2 40 3m $orient
}
wm deiconify .
vwait forever
exit 0
}
proc shadowcircle { canvas x1 y1 x2 y2 ticks width orient } {
set angle $orient
set delta [expr {180.0/$ticks}]
for {set i 0} {$i <= $ticks} {incr i} {
set a [expr {($angle+$i*$delta)}]
set b [expr {($angle-$i*$delta)}]
set color [expr {20+$i*(220/$ticks)}]
set color [format "#%x%x%x" $color $color $color]
$canvas create arc $x1 $y1 $x2 $y2 -start $a -extent $delta \
-style arc -outline $color -width $width
$canvas create arc $x1 $y1 $x2 $y2 -start $b -extent $delta \
-style arc -outline $color -width $width
}
}
main $argc $argv