Exercises, examples and other material relating to training module T219. This topic is presented on public course Tcl/Tk

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Tcl - the Tk Toolkit - training course - The Graphic Application of Tcl through Tk Tcl - the Tk Toolkit - The Graphic Application of Tcl through Tk This course takes the programmer who's already learnt to program in Tcl forward into the ... http://www.wellho.net/course/tkfull.html  [course]

Tcl/Tk - why does the canvas widget use a display list? "Tcl/Tk uses a display list when you draw on a canvas widget." OK - so what does that really mean? With most of the languages that we teach, any graphics ... http://www.wellho.net/mouth/2211_Tcl ... list-.html  [short article]

text options in Tk - colour, font, size, centring #!/usr/bin/wish # demo of text options canvas .demo -width 400 -height 380 -background white button .end -text "done" -command exit pack .demo .end -fill ... http://www.wellho.net/resources/ex.php4?item=t219/tktext  [code sample]

Drawing on a canvas !/usr/bin/wish canvas .demo -width 350 -height 200 -background white button .end -text "done" -command exit pack .demo .end -fill both -expand true ... http://www.wellho.net/resources/ex.php4?item=t219/can1  [code sample]

Histogram drawn on a canvas - generalised code # Draw a histogram on a canvas to display the # following data values which are sales for the # four quarters of a year set info {103.7 154.6 206.5 ... http://www.wellho.net/resources/ex.php4?item=t219/histo  [code sample]

Line styles on a Tk canvas #!/usr/bin/wish canvas .demo -width 400 -height 740 -background white button .end -text "done" -command exit pack .demo .end -fill both -expand true ... http://www.wellho.net/resources/ex.php4?item=t219/can4  [code sample]

Placing a GIF on a canvas image create photo box -format GIF -file library.gif canvas .democan -width 600 -height 400 .democan create image 300 200 -image box pack .democan ... http://www.wellho.net/resources/ex.php4?item=t219/imgoncanvas.tk  [code sample]

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Tcl/Tk GUIs consist largely of components such as buttons, labels entry boxes and sliders. Sometimes you'll need something that's much more graphic and for this you'll use a canvas widget. You can write to a canvas down to individual pixel level, and you can also draw lines, ovals, rectangles, text and polygons. This module studies the options for drawing to and manipulating a canvas, and introduces computer graphic techniques such as world to pixel co-ordinate transformations and display list manipulation.

This topic is presented on public course Tcl/Tk

can1	Drawing on a canvas
can2	Drawing shapes on a canvas and dragging them with the mouse
can3	Demo of different graphic objects
can4	Line styles on a Tk canvas
histo	Histogram drawn on a canvas - generalised code
imgoncanvas.tk	Placing a GIF on a canvas
tktext	text options in Tk - colour, font, size, centring

Using a Tcl/Tk canvas