Page by [Theo Verelst]

The [Gimp] drawing program is maybe not a replacement for Photoshop, but it certainly has become a powerfull (pixel and vector) drawing program, which is freely usable, and open source.

[http://82.168.209.239/Bwise/gimpbwise1.jpg]

There used to be a Tcl plugin to let tcl scripts interface with it, but that seems to have disappeared, and I think wasn't all-complete. Using the latest version Gimp2.0, I used the [Gimp Client] code to establish a connection with a running GIMP instance, and made a [bwise] blocks-with-wires drawing of the example on that page.

There are good advantages when using bwise for such a task: a block for each gimp command with inputs and outputs makes clear visually what the gimp is told to do.

Preferably, I'd like to be able to easily create (and connect) blocks for gimp commands, and probably prefab some often used blocks with functions to open an image and do some of the most common things.

Because the blocks can take parameters as inputs, it is easier to present where a user of the bwise/gimp combination can make variable dependent processing happen, for instance repeated 'running' of a graphs' functionality for different file names.

The example which follows is fully functional (at least it worked fine on RedHat 9, tcl/tk 8.4.4), though I'd say it isn't more than an experiment at the moment to see what bwise can do in such a setup, not a user-ready application.

First, the script from [Salvatore Sanfilippo], to make the connection with gimp (it could be he has updated his version on the [Gimp Client] page, I'll check it out), then the block definitions, and then connections are defined. The block definitions have no coordinates, so all blocks will end up in the left upper corner of the bwise canvas: you'll have to drag them in place for now.

A recent Bwise can be downloaded here [http://82.168.209.239/Bwise/bwise034.tcl] . The result of the below script is a text in a fresh window with colours:

[http://82.168.209.239/Bwise/gimpbwise2.jpg]

Which is done by using the right-click popup menu 'funprop' on the most left 'init' block, which fires all connected block in sequence, based on the availability of new data on all inputs, once the last block has fired, GIMP shows the image above.

Gimp can show more than one image at a time, rerunning the whole net simply generates a new image (and the previous img and drawable indices are lost). I just tried driving a redhat gimp from a XP bwise, which works fine over a network (I didn't use an X server to route the result to the XP), I didn't get gimp2 for windows to respond to socket connections, though, which is a pity.

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 # Tcl client for Gimp's Script-Fu Server.
 # Copyright(C) 2004 Salvatore Sanfilippo
 #
 # This is free software, under the terms of the GPL license version 2.
 # You can get a copy of the license from http://www.gnu.org/copyleft/gpl.html
 #
 # TODO:
 #
 # - Define more constants
 # - Write some decent example
 # - Add some higher level subcommand with sane defaults
 #   and options to specify more details, in the Tcl way.

 namespace eval gimp {}
 namespace eval gimp::method {}

 set gimp::debug 1

 ################################################################################
 # GIMP constants
 ################################################################################

 # Image type
 set gimp::RGB 0
 set gimp::GRAY 1
 set gimp::INDEXED 2

 # Layer type
 set gimp::RGB_IMAGE 0
 set gimp::RGBA_IMAGE 1
 set gimp::GRAY_IMAGE 2
 set gimp::GRAYA_IMAGE 3
 set gimp::INDEXED_IMAGE 4
 set gimp::INDEXEDA_IMAGE 5

 # Layer mode
 set gimp::NORMAL_MODE 0
 set gimp::DISSOLVE_MODE 1
 set gimp::BEHIND_MODE 2
 set gimp::MULTIPLY_MODE 3
 set gimp::SCREEN_MODE 4
 set gimp::OVERLAY_MODE 5
 set gimp::DIFFERENCE_MODE 6
 set gimp::ADDITION_MODE 7
 set gimp::SUBTRACT_MODE 8
 set gimp::SUBTRACT_MODE 8
 set gimp::DARKEN_ONLY_MODE 9
 set gimp::HUE_MODE 11
 set gimp::SATURATION_MODE 12
 set gimp::COLOR_MODE 13
 set gimp::VALUE_MODE 14
 set gimp::DIVIDE_MODE 15
 set gimp::DODGE_MODE 16
 set gimp::BURN_MODE 17
 set gimp::HARDLIGHT_MODE 18
 set gimp::SOFTLIGHT_MODE 19
 set gimp::GRAIN_EXTRACT_MODE 20
 set gimp::GRAIN_MERGE_MODE 21
 set gimp::COLOR_ERASE_MODE 22

 # Fill type
 set gimp::FOREGROUND_FILL 0
 set gimp::BACKGROUND_FILL 1
 set gimp::WHITE_FILL 2
 set gimp::TRANSPARENT_FILL 3
 set gimp::PATTERN_FILL 3

 # Units
 set gimp::PIXELS 0
 set gimp::POINTS 1

 # Connect to a running GIMP (with Script-Fu Server enabled)
 proc gimp::connect {{host 127.0.0.1} {port 10008}} {
     set fd [socket $host $port]
     fconfigure $fd -encoding binary -translation binary
     set handle "gimp-$fd"
     interp alias {} $handle {} gimp::request $fd
     set script {
 (begin
     (define (scheme-list->tcl l)
       (let ((len (length l)) (i 0) (res ""))
 	(while (< i len)
 	  (set! res (string-append res " {" (scheme->tcl (nth i l)) "}"))
 	  (set! i (+ i 1)))
 	res))

     (define (scheme->tcl o)
       (cond
 	((pair? o) (scheme-list->tcl o))
 	((number? o) (number->string o))
 	((null? o) "{}")
 	((string? o) o)))

     (define (tclinterface-get-procedure-info procname)
 	(let ((x (gimp-procedural-db-proc-info procname)))
 	    (begin
 		(set! numargs (nth 6 x))
 		(set! numvals (nth 7 x))
 		(set! tclargs "")
 		(set! tclvals "")
 		(set! i 0)
 		(while (< i numargs)
 		    (let ((procinfo (gimp-procedural-db-proc-arg procname i)))
 			(set! tclargs (string-append tclargs
 			    "{" (number->string (nth 0 procinfo)) " "
 				"{" (nth 1 procinfo) "}} ")))
 		    (set! i (+ i 1)))
 		(set! i 0)
 		(while (< i numvals)
 		    (let ((procinfo (gimp-procedural-db-proc-val procname i)))
 			(set! tclvals (string-append tclvals
 			    "{" (number->string (nth 0 procinfo)) " "
 				"{" (nth 1 procinfo) "}} ")))
 		    (set! i (+ i 1)))
 		(string-append "{" tclargs "} {" tclvals "}")))))

     }
     ::gimp::evalscheme $fd $script
     return $handle
 }

 # Use the Script-Fu Server binary protocol to evaluate a Scheme s-expression.
 proc gimp::evalscheme {fd script} {
     # Send the query...
     set script [string trim $script]
     if {$::gimp::debug} {puts "Script: $script"}
     set query "G[binary format S [string length $script]]$script"
     puts -nonewline $fd $query
     flush $fd
     # Get the reply...
     set hdr [read $fd 4]
     binary scan [string index $hdr 1] c errorcode
     binary scan [string range $hdr 2 3] S replylen
     if {$::gimp::debug} {
 	puts "Reply error code: $errorcode len: $replylen"
     }
     set reply [read $fd $replylen]
     if {$::gimp::debug} {
 	puts "Reply: $reply"
     }
     if {$errorcode} {
 	error "Script-Fu error '[string trim $reply]' executing '$script'"
     }
     return $reply
 }

 # Handle requests to Gimp handlers. Actually it's a dispatcher
 # that calls the on-the-fly binding code if needed.
 proc gimp::request {fd request args} {
     if {[catch {info args ::gimp::method::$request}]} {
 	::gimp::trytobind $fd $request
     }
     eval ::gimp::method::$request $fd $args
 }

 # Try to create bindings on-the-fly for the called Scheme function.
 proc gimp::trytobind {fd funcname} {
     set pdbname [string map [list - _] $funcname]
     set scheme "(tclinterface-get-procedure-info \"$pdbname\")"
     if {[catch {::gimp::evalscheme $fd $scheme} result]} {
 	# No PDB function with this name
 	return
     } else {
 	foreach {args vals} $result break
 	set arglist fd
 	set scheme "(scheme->tcl ($funcname "
 	foreach a $args {
 	    foreach {type name} $a break
 	    append scheme "\[tcl->scheme $type \$$name\] "
 	    lappend arglist $name
 	}
 	append scheme "))"
 	puts $scheme
 	if {[llength $vals] > 1} {
 	    proc ::gimp::method::$funcname $arglist [format {
 		::gimp::evalscheme $fd %s
 	    } "\"$scheme\""]
 	} else {
 	    proc ::gimp::method::$funcname $arglist [format {
 		lindex [::gimp::evalscheme $fd %s] 0
 	    } "\"$scheme\""]
 	}
     }
 }

 # Convert Tcl PDB arguments to Scheme's equivalent
 proc tcl->scheme {type val} {
     switch -- $type {
 	0 - 1 - 2 - 3 {
 	    # Number and IDs
 	    return $val
 	}
 	5 - 6 - 7 - 8 - 9 - 10 {
 	    # Array of different types
 	    set res "'("
 	    foreach e $val {
 		append res [switch -- $type {
 		    5 - 6 - 7 - 8 - 10 {tcl->scheme 0 $e}
 		    9 {tcl->scheme 4 $e}
 		}] " "
 	    }
 	    append res ")"
 	}
 	4 {
 	    # String
 	    set q [list $val]
 	    if {[string length $q] != [string length $val]} {
 		return "\"[string range $q 1 end-1]\""
 	    } else {
 		return "\"$val\""
 	    }
 	}
 	default {
 	    # Id of images, layers, and so on.
 	    return $val
 	}
     }
 }

 ################################################################################
 # Methods that does not have a counter-part in the Scheme environment
 ################################################################################

 # Eval a scheme script
 proc gimp::method::remote-eval {fd script} {
     ::gimp::evalscheme $fd $script
 }

 # Close the link with Gimp and remove the alias
 proc gimp::method::close fd {
     ::close $fd
     set handle "gimp-$fd"
     interp alias {} $handle {}
 }
 
 ################################################################################
 # Testing
 ################################################################################
 # The args are: host port
 # defaults: localhost 10008
 set gimp [gimp::connect]
 
 ### the Bwise part, by TV
 # fill in the place where your bwise script is here:
 source bwise343start_redhat.tcl
 
 #see above
 #source gimpinit.tcl

 # the blocks:
 newproc {} init in {width height bgcolor textcolor }
 newproc {set gimp-image-new.img [$gimp gimp-image-new ${gimp-image-new.width} ${gimp-image-new.height} $gimp::RGB]} gimp-image-new {width height} {img} 40 {} {} 27 103
 newproc {set gimp-layer-new.drawable [$gimp gimp-layer-new ${gimp-layer-new.img} ${gimp-layer-new.width} ${gimp-layer-new.height} $gimp::RGB_IMAGE "FooLayer" 100 $gimp::NORMAL_MODE]} gimp-layer-new {img width height} {drawable} 40 {} {} 137 7
 newproc {set gimp-image-undo-disable.imgcopy [$gimp gimp-image-undo-disable ${gimp-image-undo-disable.img}]} gimp-image-undo-disable img imgcopy 40 {} {} 256 133
 newproc {set  gimp-image-add-layer.out [$gimp  gimp-image-add-layer ${gimp-image-add-layer.img} ${gimp-image-add-layer.drawable} 0]}  gimp-image-add-layer {drawable img} {out} 40 {} {} 383 105
 newproc {set gimp-palette-set-foreground.out [$gimp gimp-palette-set-foreground ${gimp-palette-set-foreground.textcolor}]} gimp-palette-set-foreground textcolor out 40 {} {} 145 219
 newproc {set gimp-palette-set-background.out [$gimp gimp-palette-set-background ${gimp-palette-set-background.bgcolor}]} gimp-palette-set-background bgcolor out 40 {} {} 145 174
 newproc {set gimp-edit-fill.out [$gimp gimp-edit-fill ${gimp-edit-fill.drawable} $gimp::BACKGROUND_FILL]} gimp-edit-fill {drawable do} out  40 {} {} 470 90
 newproc {set gimp-drawable-update.out [$gimp gimp-drawable-update ${gimp-drawable-update.drawable} 0 0 ${gimp-drawable-update.width} ${gimp-drawable-update.height}]} gimp-drawable-update {drawable width height do} out 40 {} {} 561 164
 newproc {set gimp-text-fontname.out [$gimp gimp-text-fontname ${gimp-text-fontname.img} ${gimp-text-fontname.drawable} ${gimp-text-fontname.x} ${gimp-text-fontname.y} ${gimp-text-fontname.text} 0 1 ${gimp-text-fontname.size} $gimp::PIXELS ${gimp-text-fontname.font} ]} gimp-text-fontname {img drawable x y text size font do} out 40 {} {} 649 59
 newproc {set gimp-display-new.out [$gimp gimp-display-new ${gimp-display-new.img}]} gimp-display-new {img do} out 40 {} {} 735 44
 newproc {set gimp-image-undo-enable.out [$gimp gimp-image-undo-enable ${gimp-image-undo-enable.img}] } gimp-image-undo-enable {img do} out 40 {} {} 735 100


 connect wire0 init width gimp-image-new width 
 connect wire1 init height gimp-image-new height 
 connect wire2 gimp-image-new img gimp-layer-new img 
 connect wire3 init width gimp-layer-new width 
 connect wire4 init height gimp-layer-new height 
 connect wire7 gimp-image-new img gimp-image-undo-disable img 
 connect wire10 gimp-layer-new drawable gimp-image-add-layer drawable 
 connect wire11 gimp-image-new img gimp-image-add-layer img 
 connect wire13 init textcolor gimp-palette-set-foreground textcolor 
 connect wire15 init bgcolor gimp-palette-set-background bgcolor 
 connect wire21 gimp-layer-new drawable gimp-edit-fill drawable 
 connect wire22 gimp-edit-fill out gimp-drawable-update do 
 connect wire23 init height gimp-drawable-update height 
 connect wire24 init width gimp-drawable-update width 
 connect wire25 gimp-layer-new drawable gimp-drawable-update drawable 
 connect wire27 gimp-image-new img gimp-text-fontname img 
 connect wire28 gimp-layer-new drawable gimp-text-fontname drawable 
 connect wire29 gimp-drawable-update out gimp-text-fontname do 
 connect wire30 gimp-image-add-layer out gimp-edit-fill do 
 connect wire31 gimp-text-fontname out gimp-display-new do 
 connect wire32 gimp-image-new img gimp-display-new img 
 connect wire33 gimp-image-new img gimp-image-undo-enable img 
 connect wire34 gimp-display-new out gimp-image-undo-enable do


----
(I've just added coordinates to the block create functions, so they appear in place)