stippling

Canvas items can be configured with "stippling" (are there any other occurrences of stippling in Tk? Well, text has the ability to specify a bitmap to be used as a stipple pattern. Also, other toolkits, like BLT use it).

What does stippling mean though?

According to http://dictionary.reference.com/search?q=stippling&r=67 , stippling is related to painting or drawing things in short strokes or dots. It appears to be a way of representing differences in areas separately from coloring (or shading?). If you are familar with bar chart type programs - sometimes one has hatching, which is representing differences by way of parallel or crossed lines of various thicknesses, and other times you can represent the differences with stippling, various other kinds of designs in the box.

The small sequence which follows illustrates the appearance of stippling. The page on bitmaps explains more of their nature.

set bitmap_list {error gray75 gray50 gray25 gray12 hourglass
    info questhead question warning document stationery edition
    application accessory folder pfolder trash floppy ramdisk
    cdrom preferences querydoc stop note caution}

set bitmap_list {error gray75 gray50 gray25 gray12 hourglass
    info questhead question warning }


pack [canvas .c -width 1000 -height 1000 -background skyBlue]
set i 0
foreach bitmap $bitmap_list {
    incr i
    set num [expr 80 * $i]
    set num1 [expr $num - 40]
    set num2 [expr $num + 40]
    .c create oval $num1 $num1 $num2 $num2 -fill red -tag $bitmap
    .c itemconfigure $bitmap -stipple $bitmap
}
.c create oval 300 40 380 120 -fill red

Is stippling simply not available under Windows? Bob Techentin says it's so.

stevel not available on macOS as of 8.7a6