HJG 2007-07-13 - A dartboard, as specified at http://www.dartswdf.com/aa_darts/playdarts.html and http://en.wikipedia.org/wiki/Darts
Sorry, no gameplay yet. I think about adding some scoring.
package require Tk
grid [canvas .c -width 290 -height 290]
.c config -scrollregion {-145 -145 145 145}
set twopi 6.283185
set halfpi 1.570796
set SectSize 0.31415925 ;# 360/20 deg = 18 deg
proc int x {expr int($x)}
proc deg2rad deg { expr {$deg * atan(1)*8/360} }
#: Convert angle from degree to radians
proc rect_to_polar { x y } {
#: Convert rectangular co-ordinates $x, $y to polar co-ordinates $r, $theta
set r [expr { hypot( $x, $y ) }]
set theta [expr { atan2( $y, $x ) }]
return [list $r $theta]
}
proc polar_to_rect { r theta } {
#: Convert polar co-ordinates $r, $theta to rectangular co-ordinates $x, $y
set x [expr { $r * cos($theta) }]
set y [expr { $r * sin($theta) }]
return [list $x $y]
}
#########1#########2#########3#########4#########5#########6#########7#####
foreach {r1 c1 v1} {144 black Out 106 green Double 100 yellow Single \
66 red Triple 60 yellow Single 10 green DBull 4 red Bull } {
.c create oval -$r1 -$r1 $r1 $r1 -fill $c1 -tag $v1 -outline black
}
# h --> Sector
for { set h 1 } { $h <= 20 } { incr h } {
set angle [expr { $halfpi - $SectSize * $h }]
set x [expr { 0 + 130 * cos($angle) }]
set y [expr { 0 - 130 * sin($angle) }]
set Sector [lindex {x 1 18 4 13 6 10 15 2 17 3 18 7 16 8 11 14 9 12 5 20} $h]
.c create text $x $y -text $Sector -font {Helvetica -14} -fill white ;# -tag wire
}
set xm 0
set ym 0
set r 106
for {set d 9} {$d<360} {set d [expr {$d+360./20.}]} {
set rad [deg2rad $d]
set x [expr {$xm+cos($rad)*$r}]
set y [expr {$ym+sin($rad)*$r}]
.c create line $xm $ym $x $y -tag "wire"
}