image create photo i -width 30 -height 30
arrowimage i right
pack [ttk::button .l -image i -style Toolbutton]

set fontSize 12
font create entryFont -size $fontSize
pack [ttk::entry .e -font entryFont] -side left
image create photo i -width 30 -height 30
pack [ttk::button .b -image i -style Toolbutton -command [list setFont 1]] -side right
set buttonFrameHeight [expr {[winfo reqheight .b] - 30}]
proc setFont {{increment 0}} {
    global fontSize
    global buttonFrameHeight
    incr fontSize $increment
    font configure entryFont -size $fontSize
    set imageSize [expr {[winfo reqheight .e] - $buttonFrameHeight}]
    set padSize [expr {$imageSize / 8} ]
    i configure -width $imageSize -height $imageSize
    arrowimage i top $padSize $padSize
}
setFont

proc arrowimage { photoCmd dir {ipadx 0} {ipady 0} {foreground black} } {
    
    set width [$photoCmd cget -width]
    set height [$photoCmd cget -height]
    set w [expr {$width  - 2*$ipadx}]
    set h [expr {$height - 2*$ipady}]

    set x0 [expr {($width-$w)/2}]
    set y0 [expr {($height-$h)/2}]
    set x1 [expr {$x0+$w-1}]
    set y1 [expr {$y0+$h-1}]
    # > Make the frame transparent and the inside with a square
    for {set y 0} {$y < $y0} {incr y} {
        for {set x 0} {$x < $height} {incr x} {
            $photoCmd transparency set $x $y 1
        }
    }
    for {set y [expr {$y1+1}]} {$y < $height} {incr y} {
        for {set x 0} {$x < $height} {incr x} {
            $photoCmd transparency set $x $y 1
        }
    }
    for {set y $y0} {$y <= $y1} {incr y} {
        for {set x 0} {$x < $x0} {incr x} {
            $photoCmd transparency set $x $y 1
        }
    }
    for {set y $y0} {$y <= $y1} {incr y} {
        for {set x [expr {$x1+1}]} {$x < $width} {incr x} {
            $photoCmd transparency set $x $y 1
        }
    }
    $photoCmd put $foreground -to $x0 $y0 [expr {$x1+1}] [expr {$y1+1}]
    # > Paint triangles as transparency
    switch $dir {
        top - bottom {
            set h0 $x0
            set h1 $x1
            set v0 $y0
            set v1 $y1
            # > On even size move right limit one to right
            set e1 [expr {($w % 2 == 0)?1:0}]
            set fHorX 1
        }
        default {
            set h0 $y0
            set h1 $y1
            set v0 $x0
            set v1 $x1
            set e1 [expr {($h % 2 == 0)?1:0}]
            set fHorX 0
        }
    }
    switch $dir {
        top - left {
            set corVert $v0
            set DCorVert 1
        }
        default {
            set corVert $v1
            set DCorVert -1
        }
    }
    set m [expr {($h0+$h1)/2}]
    set DHor [expr {$h1 - $m}]
    set DVert [expr {$v1 - $v0}]
    set d 0
    set r 0
    for {set vertLoop 0} {$vertLoop < $DVert} {incr vertLoop} {
        set limitHor [expr {$m - $d}]
        for {set horLoop 0} {$horLoop < $limitHor} {incr horLoop} {
            $photoCmd transparency set\
                    [expr {$fHorX?$horLoop:$corVert}]\
                    [expr {$fHorX?$corVert:$horLoop}] 1
        }
        set limitHor [expr {$m + $d + 1 + $e1}]
        for {set horLoop $limitHor} {$horLoop <= $h1} {incr horLoop} {
            $photoCmd transparency set\
                    [expr {$fHorX?$horLoop:$corVert}]\
                    [expr {$fHorX?$corVert:$horLoop}] 1
        }
        incr corVert $DCorVert
        incr r $DHor
        incr d [expr { $r / $DVert } ]
        set r [expr { $r % $DVert}]
    }
}