| 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 | |
| 8 | if {![info exists widgetDemo]} { |
| 9 | error "This script should be run from the \"widget\" demo." |
| 10 | } |
| 11 | |
| 12 | set w .plot |
| 13 | catch {destroy $w} |
| 14 | toplevel $w |
| 15 | wm title $w "Plot Demonstration" |
| 16 | wm iconname $w "Plot" |
| 17 | positionWindow $w |
| 18 | set c $w.c |
| 19 | |
| 20 | 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." |
| 21 | pack $w.msg -side top |
| 22 | |
| 23 | frame $w.buttons |
| 24 | pack $w.buttons -side bottom -fill x -pady 2m |
| 25 | button $w.buttons.dismiss -text Dismiss -command "destroy $w" |
| 26 | button $w.buttons.code -text "See Code" -command "showCode $w" |
| 27 | pack $w.buttons.dismiss $w.buttons.code -side left -expand 1 |
| 28 | |
| 29 | canvas $c -relief raised -width 450 -height 300 |
| 30 | pack $w.c -side top -fill x |
| 31 | |
| 32 | set 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 $plotFont -fill brown |
| 37 | |
| 38 | for {set i 0} {$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 $plotFont |
| 42 | } |
| 43 | for {set i 0} {$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 | |
| 49 | foreach 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" |
| 64 | bind $c <B1-Motion> "plotMove $c %x %y" |
| 65 | |
| 66 | set plot(lastX) 0 |
| 67 | set 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 | |
| 77 | proc 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 | |
| 94 | proc 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 | } |