1# plot.tcl -- 2# 3# This demonstration script creates a canvas widget showing a 2-D 4# plot with data points that can be dragged with the mouse. 5# 6# RCS: @(#) $Id: plot.tcl,v 1.3 2001/06/14 10:56:58 dkf Exp $ 7 8if {![info exists widgetDemo]} { 9 error "This script should be run from the \"widget\" demo." 10} 11 12set w .plot 13catch {destroy $w} 14toplevel $w 15wm title $w "Plot Demonstration" 16wm iconname $w "Plot" 17positionWindow $w 18set c $w.c 19 20label $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." 21pack $w.msg -side top 22 23frame $w.buttons 24pack $w.buttons -side bottom -fill x -pady 2m 25button $w.buttons.dismiss -text Dismiss -command "destroy $w" 26button $w.buttons.code -text "See Code" -command "showCode $w" 27pack $w.buttons.dismiss $w.buttons.code -side left -expand 1 28 29canvas $c -relief raised -width 450 -height 300 30pack $w.c -side top -fill x 31 32set plotFont {Helvetica 18} 33 34$c create line 100 250 400 250 -width 2 35$c create line 100 250 100 50 -width 2 36$c create text 225 20 -text "A Simple Plot" -font $plotFont -fill brown 37 38for {set i 0} {$i <= 10} {incr i} { 39 set x [expr {100 + ($i*30)}] 40 $c create line $x 250 $x 245 -width 2 41 $c create text $x 254 -text [expr {10*$i}] -anchor n -font $plotFont 42} 43for {set i 0} {$i <= 5} {incr i} { 44 set y [expr {250 - ($i*40)}] 45 $c create line 100 $y 105 $y -width 2 46 $c create text 96 $y -text [expr {$i*50}].0 -anchor e -font $plotFont 47} 48 49foreach point { 50 {12 56} {20 94} {33 98} {32 120} {61 180} {75 160} {98 223} 51} { 52 set x [expr {100 + (3*[lindex $point 0])}] 53 set y [expr {250 - (4*[lindex $point 1])/5}] 54 set item [$c create oval [expr {$x-6}] [expr {$y-6}] \ 55 [expr {$x+6}] [expr {$y+6}] -width 1 -outline black \ 56 -fill SkyBlue2] 57 $c addtag point withtag $item 58} 59 60$c bind point <Any-Enter> "$c itemconfig current -fill red" 61$c bind point <Any-Leave> "$c itemconfig current -fill SkyBlue2" 62$c bind point <1> "plotDown $c %x %y" 63$c bind point <ButtonRelease-1> "$c dtag selected" 64bind $c <B1-Motion> "plotMove $c %x %y" 65 66set plot(lastX) 0 67set plot(lastY) 0 68 69# plotDown -- 70# This procedure is invoked when the mouse is pressed over one of the 71# data points. It sets up state to allow the point to be dragged. 72# 73# Arguments: 74# w - The canvas window. 75# x, y - The coordinates of the mouse press. 76 77proc plotDown {w x y} { 78 global plot 79 $w dtag selected 80 $w addtag selected withtag current 81 $w raise current 82 set plot(lastX) $x 83 set plot(lastY) $y 84} 85 86# plotMove -- 87# This procedure is invoked during mouse motion events. It drags the 88# current item. 89# 90# Arguments: 91# w - The canvas window. 92# x, y - The coordinates of the mouse. 93 94proc plotMove {w x y} { 95 global plot 96 $w move selected [expr {$x-$plot(lastX)}] [expr {$y-$plot(lastY)}] 97 set plot(lastX) $x 98 set plot(lastY) $y 99} 100