[FF] 2007-05-19 - MimeTexBuffer aims to be an interactive math formula edit buffer. See it in action:

[http://www.freemove.it/images/MimeTexBuffer.gif]

or try the code.

This is preliminary draft buggy crap junk code of a project I'll work in the near future.
I post the code just right now so that you can enjoy hacking it :P

I'm a bit tired and won't put my hands over it for a couple of days ^_^

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 #!/bin/sh
 # This line continues for Tcl, but is a single line for 'sh' \
 exec tclsh "$0" ${1+"$@"}
 
 package require Tk 8.4
 package require base64
 
 grid [canvas .c] -row 0 -columnspan 2 -sticky news
 
 set img ""
 set caret "@@@@8976@@@@"
 set buf $caret
 
 proc render e {
	global img
	.c delete eee
	catch {image delete $img}
	set p [open [list |mimetex -d "$e"] r]
	fconfigure $p -translation binary -encoding binary
	set rawData [base64::encode [read $p]]
	close $p
	set img [image create photo -data $rawData]
	.c create image 10 10 -image $img -tags eee -anchor nw
 }
 
 proc kp {w keycode keysym keysym_s} {
	global buf caret
	set caretpos [lsearch $buf $caret]
	set len [llength $buf]
	if [regexp {^[a-z0-9]$} $keysym_s] {
		set buf [linsert $buf $caretpos $keysym_s]
	} else { switch -- $keysym_s {
		plus        { set buf [linsert $buf $caretpos "+"]          }
		minus       { set buf [linsert $buf $caretpos "-"]          }
		asterisk    { set buf [linsert $buf $caretpos " \\cdot "]   }
		parentleft  { set buf [linsert $buf $caretpos " \\left( "]  }
		parentright { set buf [linsert $buf $caretpos " \\right) "] }
		Escape      { set buf [linsert $buf $caretpos "\} "]         }
		slash {
			set buf [linsert $buf [expr $caretpos+0] " \\frac\{"]
			set buf [linsert $buf [expr $caretpos+2] "\}\{"]
			set buf [linsert $buf [expr $caretpos+3] "\} "]
		}
		BackSpace {
			if {$caretpos > 0} {
				set newbuf [list]
				eval lappend newbuf [lrange $buf 0 [expr $caretpos-2]]
				lappend newbuf $caret
				eval lappend newbuf [lrange $buf [expr $caretpos+1] end]
				set buf $newbuf
				unset newbuf
			}
		}
		Delete {
			if {$len > 1 && [expr $caretpos+1] < $len} {
				set newbuf [list]
				eval lappend newbuf [lrange $buf 0 [expr $caretpos-2]]
				lappend newbuf [lindex $buf [expr $caretpos-1]]
				lappend newbuf $caret
				eval lappend newbuf [lrange $buf [expr $caretpos+2] end]
				set buf $newbuf
				unset newbuf
			}
		}
		Left {
			if {$caretpos > 0} {
				set newbuf [list]
				eval lappend newbuf [lrange $buf 0 [expr $caretpos-2]]
				lappend newbuf $caret
				lappend newbuf [lindex $buf [expr $caretpos-1]]
				eval lappend newbuf [lrange $buf [expr $caretpos+1] end]
				set buf $newbuf
				unset newbuf
			}
		}
		Right {
			if {[expr $caretpos+1] < $len} {
				set newbuf [list]
				eval lappend newbuf [lrange $buf 0 [expr $caretpos-1]]
				lappend newbuf [lindex $buf [expr $caretpos+1]]
				lappend newbuf $caret
				eval lappend newbuf [lrange $buf [expr $caretpos+2] end]
				set buf $newbuf
				unset newbuf
			}
		}
	}}
	set len [llength $buf]
	foreach sym {sqrt sin cos tan atan phi pi} {
		set sl [string length $sym]
		for {set i 0} {$i < [expr $len-$sl]} {incr i} {
			set m [join [lrange $buf $i [expr $i+$sl-1]] ""]
			if {$m == $sym} {
				set newbuf [lrange $buf 0 [expr $i-1]]
				lappend newbuf " \\$sym\{ "
				eval lappend newbuf [lrange $buf [expr $i+$sl] end]
				set buf $newbuf
				unset newbuf
				break
			}
		}
	}
	set buf_p [string map [list $caret " \\mid "] [join $buf ""]]
	puts "buf={${buf}}"
	render $buf_p
 }

 bind . <KeyPress> {kp %W %k %N %K}
----