# plot.tcl -- # # This demonstration script creates a canvas widget showing a 2-D # plot with data points that can be dragged with the mouse. # # RCS: @(#) $Id: plot.tcl,v 1.1.4.1 1998/09/30 02:17:51 stanton Exp $ if {![info exists widgetDemo]} { error "This script should be run from the \"widget\" demo." } set w .plot catch {destroy $w} toplevel $w wm title $w "Plot Demonstration" wm iconname $w "Plot" positionWindow $w set c $w.c label $w.msg -font $font -wraplength 4i -justify left -text "This window displays a canvas widget containing a simple 2-dimensional plot. You can doctor the data by dragging any of the points with mouse button 1." pack $w.msg -side top frame $w.buttons pack $w.buttons -side bottom -fill x -pady 2m button $w.buttons.dismiss -text Dismiss -command "destroy $w" button $w.buttons.code -text "See Code" -command "showCode $w" pack $w.buttons.dismiss $w.buttons.code -side left -expand 1 canvas $c -relief raised -width 450 -height 300 pack $w.c -side top -fill x set plotFont {Helvetica 18} $c create line 100 250 400 250 -width 2 $c create line 100 250 100 50 -width 2 $c create text 225 20 -text "A Simple Plot" -font $plotFont -fill brown for {set i 0} {$i <= 10} {incr i} { set x [expr {100 + ($i*30)}] $c create line $x 250 $x 245 -width 2 $c create text $x 254 -text [expr 10*$i] -anchor n -font $plotFont } for {set i 0} {$i <= 5} {incr i} { set y [expr {250 - ($i*40)}] $c create line 100 $y 105 $y -width 2 $c create text 96 $y -text [expr $i*50].0 -anchor e -font $plotFont } foreach point {{12 56} {20 94} {33 98} {32 120} {61 180} {75 160} {98 223}} { set x [expr {100 + (3*[lindex $point 0])}] set y [expr {250 - (4*[lindex $point 1])/5}] set item [$c create oval [expr $x-6] [expr $y-6] \ [expr $x+6] [expr $y+6] -width 1 -outline black \ -fill SkyBlue2] $c addtag point withtag $item } $c bind point "$c itemconfig current -fill red" $c bind point "$c itemconfig current -fill SkyBlue2" $c bind point <1> "plotDown $c %x %y" $c bind point "$c dtag selected" bind $c "plotMove $c %x %y" set plot(lastX) 0 set plot(lastY) 0 # plotDown -- # This procedure is invoked when the mouse is pressed over one of the # data points. It sets up state to allow the point to be dragged. # # Arguments: # w - The canvas window. # x, y - The coordinates of the mouse press. proc plotDown {w x y} { global plot $w dtag selected $w addtag selected withtag current $w raise current set plot(lastX) $x set plot(lastY) $y } # plotMove -- # This procedure is invoked during mouse motion events. It drags the # current item. # # Arguments: # w - The canvas window. # x, y - The coordinates of the mouse. proc plotMove {w x y} { global plot $w move selected [expr $x-$plot(lastX)] [expr $y-$plot(lastY)] set plot(lastX) $x set plot(lastY) $y }