Tcl/Tk Cookbook - Using the Canvas

Part-II - Step 2: Map the data and tag and bind country names.

The Western European map data is adopted to the Tk canvas coordinate system from the original coordinates given in PHIGS Programming Manual, by Tom Gaskins, Appendix D

The procedure to create the mapdata is simple and is described below:

For each country, the Tk widget command "$w" where $w points to the canvas, is invoked to create a closed filled polygon with given points forming the edges. Then the filled region is tagged with the country's name. The tag is associated with a binding for Button-1 (left mouse button) to show the coutry's name in the entry widget when the user clicks within the country's borders. (Experiment to see what happens when you click on the borders.)

$w create polygon  \
1.33039 0.57027 1.36029 0.59123 1.34591 0.50223 1.34591 0.44262 \
1.33314 0.41707 1.32797 0.37687 1.30972 0.35746 1.27992 0.3532 \
1.2565 0.33617 1.24296 0.32417 1.21179 0.32979 1.19902 0.34469 \
1.17347 0.34469 1.14416 0.36309 1.12876 0.34895 1.14792 0.34043 \
1.14154 0.31488 1.11386 0.31488 1.10109 0.29998 1.07054 0.29423 \
1.03341 0.29185 1.02019 0.32766 1.02019 0.34895 1.02861 0.38514 \
1.02861 0.41158 1.00742 0.39152 0.98251 0.38164 0.98251 0.4043 \
0.96484 0.39152 0.94359 0.41876 0.93879 0.48524 0.88614 0.51518 \
0.88614 0.60021 0.88852 0.64209 0.91374 0.65977 0.89988 0.68344 \
0.99688 0.72716 0.96694 0.81694 1.07471 0.82592 1.25673 0.82354 \
1.30943 0.73852 1.21301 0.62593 1.33039 0.57027 \
-fill green   -tag germany
$w bind germany  {showName Germany}
 

$w create polygon \
0.88852 0.64209 0.91374 0.65977 \
0.89988 0.68344 0.86993 0.67863 0.88852 0.64209\
  -fill bisque4 -tag luxemburg
$w bind luxemburg  {showName Luxemburg}


$w create polygon \
1.07471 0.82592 1.25673 0.82354 1.30943 0.73852 1.34288 0.75019 \
1.37815 0.7365 1.407 0.71653 1.47287 0.73372 1.49383 0.78462 \
1.47272 0.80309 1.44708 0.80309 1.45028 0.83194 1.43395 0.86727 \
1.4038 0.88484 1.36853 0.87852 1.34449 0.90247 1.30046 0.89721 \
1.24831 0.88074 1.21782 0.85586 1.16335 0.85278 1.128 0.86965 \
1.0867 0.86067 1.07471 0.82592\
  -fill PeachPuff2 -tag austria
$w bind austria  {showName Austria}


$w create polygon  \
0.94359 0.41876 0.93879 0.48524 0.88614 0.51518 0.88614 0.60021 \
0.83344 0.54989 0.7526 0.55649 0.78826 0.53219 0.81711 0.51936 \
0.8091 0.50333 0.81711 0.48249 0.83314 0.4841 0.85719 0.48249 \
0.81391 0.46486 0.8123 0.44402 0.82513 0.41998 0.85858 0.41876 \
0.94359 0.41876\
  -fill LemonChiffon1 -tag netherlands
$w bind netherlands  {showName Netherlands}

$w create polygon \
0.7526 0.55649 0.83344 0.54989 0.88614 0.60021 0.88852 0.64209 \
0.86993 0.67863 0.82833 0.65084 0.82994 0.61554 0.8091 0.62035 \
0.79948 0.64439 0.77864 0.64119 0.76843 0.608 0.7113 0.57265 \
0.72895 0.55783 0.7526 0.55649\
  -fill honeydew1 -tag belgium
$w bind belgium  {showName Belgium}


$w create polygon \
1.03341 0.29185 1.02069 0.26129 1.0011 0.24153 0.99344 0.20518 \
1.00786 0.17953 1.01245 0.13976 1.03672 0.11381 1.08481 0.10259 \
1.10084 0.08175 1.128 0.07808 1.1345 0.11221 1.10565 0.13305 \
1.10227 0.16311 1.11847 0.17793 1.14251 0.16992 1.14837 0.18824 \
1.12328 0.22121 1.07951 0.22954 1.0816 0.28052 1.07054 0.29423 \
1.03341 0.29185\
   -fill LavenderBlush1 -tag denmark 
$w bind denmark  {showName Denmark}

$w create polygon \
1.1345 0.23724 1.11366 0.24045 1.11045 0.25648 1.12488 0.2709 \
1.13129 0.28533 1.14412 0.27571 1.14893 0.25327 1.1345 0.23724\
   -fill LavenderBlush1 -tag fyn
$w bind fyn  {showName Fyn}

$w create polygon \
1.22587 0.20198 1.20182 0.21159 1.20022 0.22602 1.21465 0.23884 \
1.19862 0.24846 1.18259 0.23724 1.1874 0.22281 1.16976 0.20999 \
1.15854 0.23243 1.16335 0.26129 1.18099 0.27892 1.20022 0.27251 \
1.16656 0.30296 1.21304 0.28373 1.20984 0.2677 1.22747 0.26129 \
1.23388 0.23564 1.21946 0.2164 1.23709 0.20999 1.22587 0.20198\
   -fill LavenderBlush1 -tag  sjaelland

$w bind sjaelland  {showName Sjaelland}

$w create polygon \
0.7113 0.57265 0.76843 0.608 0.77864 0.64119 0.79948 0.64439 \
0.8091 0.62035 0.82994 0.61554 0.82833 0.65084 0.86993 0.67863 \
0.89988 0.68344 0.99688 0.72716 0.96694 0.81694 0.93413 0.82874 \
0.91169 0.87183 0.88614 0.89721 0.88764 0.9153 0.90688 0.91183 \
0.9181 0.92972 0.93879 0.93433 0.94535 0.98102 0.92743 1.00315 \
0.94695 1.03552 0.97115 1.04193 0.97115 1.07444 0.89749 1.1253 \
0.78253 1.09298 0.73405 1.11632 0.73405 1.16902 0.65142 1.16664 \
0.62636 1.13811 0.58628 1.12689 0.55583 1.13212 0.51255 1.1186 \
0.51255 1.09002 0.4869 1.11059 0.46701 1.10438 0.47889 1.08842 \
0.49011 1.04834 0.51255 1.00346 0.51095 0.9698 0.49812 0.90408 \
0.49331 0.88965 0.47728 0.88804 0.45965 0.87682 0.45645 0.85759 \
0.47272 0.84689 0.45484 0.83515 0.43721 0.83996 0.41156 0.83675 \
0.41797 0.82553 0.40515 0.83194 0.36988 0.81751 0.34584 0.81591 \
0.33109 0.80558 0.32981 0.78866 0.31699 0.77584 0.31076 0.75468 \
0.3234 0.73897 0.34744 0.73737 0.36508 0.72614 0.38752 0.73416 \
0.41156 0.76141 0.4324 0.74378 0.46767 0.74378 0.48317 0.7523 \
0.48209 0.71492 0.46767 0.69248 0.4628 0.67625 0.49331 0.67004 \
0.51736 0.68287 0.57026 0.68126 0.59396 0.69003 0.60552 0.68126 \
0.5943 0.67325 0.60552 0.65401 0.64239 0.62195 0.66039 0.58881 \
0.7113 0.57265 -fill  SlateBlue1 -tag  france
$w bind france  {showName France}


$w create polygon \
0.96694 0.81694 0.93413 0.82874 0.91169 0.87183 0.88614 0.89721 \
0.88764 0.9153 0.90688 0.91183 0.9181 0.92972 0.93879 0.93433 \
0.98863 0.91156 0.99825 0.89125 1.03191 0.89927 1.0472 0.93433 \
1.08 0.89285 1.128 0.86965 1.0867 0.86067 1.07471 0.82592 0.96694 0.81694\
    -fill RoyalBlue1  -tag switzerland

$w bind switzerland  {showName Switzerland}



$w create polygon \
1.30046 0.96185 1.30046 0.89721 1.24831 0.88074 1.21782 0.85586 \
1.16335 0.85278 1.128 0.86965 1.08 0.89285 1.0472 0.93433 1.03191 \
0.89927 0.99825 0.89125 0.98863 0.91156 0.93879 0.93433 0.94535 \
0.98102 0.92743 1.00315 0.94695 1.03552 0.97115 1.04193 0.97115 \
1.07444 0.99504 1.07239 1.02229 1.05475 1.0406 1.0379 1.07038 \
1.04193 1.11526 1.05636 1.13771 1.08361 1.13931 1.11246 1.15534 \
1.1333 1.16934 1.16664 1.20182 1.1894 1.22907 1.21184 1.26915 \
1.22467 1.3509 1.27596 1.35891 1.28879 1.37174 1.28879 1.38616 \
1.2952 1.39097 1.30482 1.40861 1.30642 1.41662 1.33046 1.41983 \
1.36413 1.42944 1.38817 1.41983 1.40901 1.42624 1.42664 1.41181 \
1.44107 1.39739 1.42824 1.38136 1.43145 1.3525 1.44588 1.29319 \
1.44748 1.27556 1.45229 1.25793 1.45069 1.24991 1.46832 1.27075 \
1.47313 1.28037 1.46832 1.30762 1.49076 1.3493 1.5132 1.37975 \
1.53244 1.39739 1.52923 1.4054 1.5132 1.39739 1.49236 1.39578 \
1.4603 1.42784 1.43786 1.44387 1.44267 1.46311 1.42344 1.47433 \
1.39618 1.49383 1.3876 1.49677 1.37695 1.49517 1.3513 1.48395 \
1.33688 1.47112 1.32886 1.47112 1.31123 1.48395 1.2984 1.50478 \
1.30161 1.51921 1.31443 1.53364 1.31283 1.54806 1.32726 1.56987 \
1.33367 1.56987 1.31631 1.56089 1.2968 1.53524 1.28237 1.50959 \
1.27596 1.48074 1.25032 1.44067 1.23108 1.43105 1.21665 1.44067 \
1.20223 1.43105 1.19261 1.37013 1.18139 1.33006 1.14933 1.31243 \
1.12048 1.29319 1.0804 1.28037 1.06758 1.25953 1.06918 1.2451 \
1.05475 1.24831 1.03231 1.2451 1.01147 1.23228 0.98903 1.23869 \
0.96819 1.27235 0.9698 1.30046 0.96185\
   -fill  SteelBlue1 -tag italy  
$w bind italy  {showName Italy}

$w create polygon \
1.06557 1.12849 1.04794 1.1365 1.05275 1.15253 1.03672 1.16376 \
1.0271 1.18139 1.03031 1.20223 1.05275 1.22627 1.07038 1.23429 \
1.08481 1.21665 1.07359 1.20543 1.08641 1.17978 1.0832 1.13811 \
1.07198 1.10284 1.06557 1.12849 \
  -fill SteelBlue1 -tag sardinia
$w bind sardinia  {showName Sardinia}

$w create polygon  \
1.06076 1.24551 1.02389 1.26154 1.00786 1.25512 1.01588 1.2407 \
0.99985 1.25673 1.00786 1.26955 1.01909 1.28077 1.0271 1.31123 \
1.01588 1.33046 1.00786 1.31924 1.01428 1.34008 1.00786 1.36573 \
1.02389 1.38496 1.04794 1.38657 1.04794 1.37214 1.05916 1.37214 \
1.06878 1.37855 1.07679 1.36733 1.07519 1.34329 1.0832 1.31924 \
1.07679 1.2984 1.09282 1.2952 1.09282 1.27276 1.07359 1.2439 \
1.06076 1.24551\
   -fill SteelBlue1 -tag corsica
$w bind corsica  {showName Corsica}

$w create polygon  \
0.73405 1.16902 0.65142 1.16664 0.62636 1.13811 0.58628 1.12689 \
0.55583 1.13212 0.51255 1.1186 0.51255 1.09002 0.4869 1.11059 \
0.46701 1.10438 0.44042 1.10765 0.41316 1.09803 0.33302 1.09002 \
0.26409 1.09322 0.21921 1.082 0.17913 1.07559 0.15509 1.08681 \
0.13585 1.09803 0.11341 1.09322 0.08776 1.10765 0.05988 1.13252 \
0.05731 1.15253 0.06532 1.17337 0.0783 1.18494 0.0783 1.19581 \
0.08502 1.20701 0.11982 1.19742 0.13265 1.21195 0.12143 1.22948 \
0.15348 1.2137 0.18875 1.21098 0.22753 1.21993 0.21528 1.24551 \
0.19196 1.26314 0.19148 1.2952 0.16586 1.34868 0.14066 1.3513 \
0.17432 1.39618 0.16474 1.41863 0.17753 1.45389 0.15348 1.47313 \
0.16344 1.50077 0.19837 1.5132 0.23203 1.53404 0.23684 1.55808 \
0.26942 1.57201 0.29615 1.56581 0.31218 1.54847 0.33943 1.54366 \
0.35866 1.54686 0.37149 1.53885 0.40355 1.53083 0.434 1.53244 \
0.45805 1.52603 0.49011 1.48916 0.50774 1.4587 0.543 1.43786 \
0.57667 1.40741 0.58468 1.38336 0.56545 1.38336 0.55423 1.36573 \
0.55904 1.34008 0.57506 1.31123 0.60552 1.27596 0.67765 1.2439 \
0.7017 1.23108 0.72735 1.19742 0.73405 1.16902 \
    -fill  LightSkyBlue1  -tag spain
$w bind spain  {showName Spain}


$w create polygon \
0.08502 1.20701 0.11982 1.19742 0.13265 1.21195 0.12143 1.22948 \
0.15348 1.2137 0.18875 1.21098 0.22753 1.21993 0.21528 1.24551 \
0.19196 1.26314 0.19148 1.2952 0.16586 1.34868 0.14066 1.3513 \
0.17432 1.39618 0.16474 1.41863 0.17753 1.45389 0.15348 1.47313 \
0.16344 1.50077 0.12784 1.5148 0.107 1.50704 0.08264 1.50975 \
0.06692 1.5132 0.06692 1.49717 0.08662 1.46992 0.0851 1.41992 \
0.05269 1.40376 0.04609 1.36573 0.05731 1.34649 0.05089 1.34329 \
0.0722 1.28558 0.08502 1.2070\
    -fill SlateGray2  -tag portugal
$w bind portugal  {showName Portugal}


$w create polygon \
0.29218 0.00863 0.32019 0.0 0.35225 0.00481 0.38271 0.0 0.39335 \
0.00621 0.38591 0.03847 0.36508 0.06893 0.34744 0.07214 0.35225 \
0.07855 0.33589 0.08944 0.35706 0.09618 0.43721 0.10259 0.434 \
0.12183 0.42439 0.15549 0.40355 0.18755 0.38676 0.20037 0.38676 \
0.21159 0.42118 0.21961 0.4742 0.24333 0.4869 0.2677 0.52698 \
0.30777 0.56224 0.34784 0.573 0.37687 0.55743 0.38151 0.5382 \
0.3783 0.51896 0.3783 0.54544 0.38644 0.57186 0.39593 0.58435 \
0.41876 0.56402 0.44632 0.57506 0.45204 0.61834 0.44402 0.65142 \
0.4601 0.63117 0.51936 0.59813 0.54513 0.60232 0.55463 0.62796 \
0.55302 0.63764 0.57027 0.56705 0.60913 0.49171 0.61073 0.42599 \
0.62035 0.38591 0.61233 0.36027 0.63317 0.33462 0.6492 0.30577 \
0.65081 0.28012 0.65561 0.25743 0.65349 0.26249 0.64439 0.28813 \
0.62997 0.30897 0.60111 0.33783 0.58028 0.37149 0.57867 0.38591 \
0.56104 0.40515 0.55302 0.42091 0.53135 0.37719 0.55231 0.33302 \
0.54501 0.29935 0.52257 0.28974 0.50494 0.34725 0.47146 0.3218 \
0.45204 0.33141 0.43441 0.31218 0.42158 0.32821 0.41196 0.33622 \
0.4296 0.36668 0.41677 0.40475 0.40682 0.40194 0.38311 0.4167 \
0.34693 0.39874 0.34784 0.38431 0.34784 0.36828 0.33182 0.37469 \
0.30617 0.39578 0.29185 0.3795 0.29014 0.36027 0.30617 0.33783 \
0.31098 0.29455 0.30617 0.28333 0.26609 0.29218 0.2158 0.24846 \
0.26191 0.24165 0.24045 0.26569 0.20037 0.27363 0.16548 0.24966 \
0.16831 0.2323 0.16072 0.24004 0.11381 0.20157 0.10419 0.20638 \
0.08817 0.22081 0.09458 0.21279 0.08175 0.22722 0.07694 0.24325 \
0.1074 0.24646 0.06733 0.29218 0.00863\
   -fill  LightSteelBlue1 -tag gb

$w bind gb  {showName "Great Britain"}


$w create polygon \
0.216 0.02244 0.18875 0.03847 0.18394 0.07374 0.17432 0.10099 \
0.14707 0.13144 0.18394 0.109 0.19676 0.07053 0.22241 0.04008 0.216 0.02244\
    -fill LightSteelBlue1 -tag hebrides
$w bind  hebrides  {showName Hebrides}

$w create polygon  \
0.17432 0.27327 0.22081 0.27571 0.23363 0.29655 0.25287 0.30937 \
0.25768 0.33502 0.22753 0.36309 0.20592 0.32898 0.1449 0.34693 \
0.12155 0.32417 0.1497 0.29185 0.17432 0.27327\
    -fill LightCyan1 -tag  nireland
$w bind nireland  {showName "Northern Ireland"}

$w create polygon  \
0.22753 0.36309 0.20592 0.32898 0.1449 0.34693 0.12155 0.32417 \
0.1497 0.29185 0.12155 0.27807 0.10539 0.29495 0.10219 0.31098 \
0.08295 0.32701 0.09637 0.34272 0.07654 0.34624 0.06372 0.35586 \
0.04609 0.35265 0.02525 0.35105 0.01135 0.36547 0.02756 0.3783 \
0.02756 0.41158 0.0525 0.41677 0.07604 0.42056 0.03486 0.45524 \
0.03232 0.47146 0.04769 0.47146 0.08502 0.46248 0.04929 0.47769 \
0.02044 0.47929 0.0 0.4966 0.0 0.51135 0.03166 0.50814 0.03654 \
0.51995 0.01616 0.52417 0.01616 0.53853 0.04609 0.53219 0.07013 \
0.53379 0.15669 0.51295 0.19676 0.50974 0.21133 0.4966 0.22562 \
0.42799 0.21921 0.39914 0.22753 0.36309\
   -fill SpringGreen1 -tag eire

$w bind eire  {showName Eire}

Display the data

Append the following script to the file: set countries {germany luxemburg austria netherlands belgium \ denmark fyn sjaelland france switzerland italy sardinia \ corsica spain portugal gb hebrides nireland eire} foreach c $countries { $w scale $c 0 0 300 300 }

The first line creates an array called "countries" whose elements are the tags created.

The canvas widget specific command scale takes five arguments and rescales all the items identified by the tag given by the first argument. The second and third arguments are used as origins for the scaling operation and the fourth and fifth the scale factors in the x and y directions. This scaling operation is called repeatedly to display the data centred within the canvas widgets visible region.

The result would be: