Joystick position: Difference between revisions

=={{header|Tcl}}==

{{libheader|Tk}}

{{libheader|mkLibsdl}} <!-- from http://mkextensions.sourceforge.net/ -->

<lang tcl>package require Tk 8.6

package require mkLibsdl

# This code assumes we're dealing with the first pair of axes on the first

# joystick; modern joysticks are complex...

# Callback for all joystick activity

proc display {joyDict} {

global x y buttons message

set axis -1

dict with joyDict {

if {$joystick != 0} return

if {[info exist button]} {

# Handle button presses...

set buttons($button) $value

set message "Buttons:"

foreach b [lsort -integer [array names buttons]] {

if {$buttons($b)} {

lappend message $b

}

}

} else {

# Handle joystick movement...

if {$axis == -1} return

set value [expr {$value / 32768.0 * 100 + 120}]

if {$axis == 0} {

set x $value

} elseif {$axis == 1} {

set y $value

}

.c coords xhairV $x [expr {$y-5}] $x [expr {$y+5}]

.c coords xhairH [expr {$x-5}] $y [expr {$x+5}] $y

}

}

}

# Make a GUI

set message "Buttons:"

pack [canvas .c -width 240 -height 240] [label .l -textvariable message]

set x [set y 120]

.c create line {120 115 120 125} -tags xhairV

.c create line {115 120 125 120} -tags xhairH

joystick event eval {display [joystick event peek]}</lang>