[...]
What is a tiled image? A tiled image is the behavior of a widget to display one or more repetitions of an image. The number of repetitions depends on the size of the widget and the size of the image.
When would I use a tiled image? If one wanted a background that had a textured feel to it, a small image , tiled, can provide that sort of optical illusion.
BLT (?) and Xbit support tiled images. With the latter,
set tiled_image [image create gimg tiledImage -file image_file_name -tile 1]
can be used anywhere that a conventional Tk image is valid (true?).
Saverio Castellano offers,
proc SetTiledBackground {cv img} {
set h [image height $img]
set w [image width $img]
set width [$cv cget -width]
set height [$cv cget -height]
set row [expr $h/2]
set col [expr $w/2]
while {$row<$height} {
set col [expr $w/2]
while {$col<$width} {
$cv create image $col $row -image $img
incr col $w
}
incr row $h
}
}Bryan Oakley (09 July 2003) provides a different variation which can be bound to the widget's <Configure> event so it will be retiled as the widget grows
# usage: tile canvasWidget ?image?
proc tile {canvas args} {
set oldImage [$canvas itemcget tile -image]
switch -exact [llength $args] {
0 {set image $oldImage}
1 {set image [lindex $args 0]}
default {
return -code error "usage: tile path ?image?"
}
}
if {$image != $oldImage
|| [string length $image] == 0} {
$canvas delete all
}
if {[string length $image] == 0} return
set imageHeight [image height $image]
set imageWidth [image width $image]
set width [winfo width $canvas]
set height [winfo height $canvas]
set x 0
while {$x < $width} {
set y 0
while {$y < $height} {
# see if there's already a tile here
set tags [$canvas gettags $x/$y]
if {$tags == ""} {
$canvas create image $x $y \
-image $image \
-anchor nw \
-tags [list tile $x/$y] \
}
incr y $imageHeight
}
incr x $imageWidth
}
}Here's some code to test it:
image create photo question -data {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}
canvas .c
tile .c question
bind .c <Configure> [list tile %W]
pack .c -side top -fill both -expand yDKF: I prefer to create a single pre-tiled image of the required size when the canvas isn't too large; the memory consumption is more, but the script is much shorter...
image create photo foo -data {...}
$canvas create image 0 0 -anchor nw -image [image create photo foo-tiled]
foo-tiled copy foo -to 0 0 [winfo width $canvas] [winfo height $canvas]
# Yes, that's all it takes folks! photo image copying tiles for you!(Bryan Oakley sez: very impressive! Nice job, Donal)