# these simple samples have been developped by C. Mertz mertz@cena.fr in perl
# tcl version by Jean-Paul Imbert imbert@cena.fr

if {![info exists zincDemo]} {
    error "This script should be run from the zinc-widget demo."
}

set w .fillRule
catch {destroy $w}
toplevel $w
wm title $w "Zinc Fillrule Demonstration"
wm iconname $w "Fillrule"

set defaultfont [font create -family Helvetica -size 10 -weight bold]

frame $w.buttons
pack $w.buttons -side bottom -fill x -pady 2m
button $w.buttons.dismiss -text Dismiss -command "destroy $w"
button $w.buttons.code -text "See Code" -command "showCode $w"
pack $w.buttons.dismiss $w.buttons.code -side left -expand 1


####### This file has been largely inspired from figure 11-3
####### of "The OpenGL Programming Guide 3rd Edition The 
####### Official Guide to Learning OpenGL Version 1.2" ISBN 0201604582

####### it illustrates the use of :
#######  -fillrule attribute of curves
#######  contour coords and clone method

set imagePath [file join $zinc_library demos images]
set texture [image create photo -file [file join $imagePath paper-grey1.gif]]

zinc $w.zinc -width 550 -height 680 -font 10x20 -borderwidth 0 -tile $texture
pack $w.zinc


$w.zinc add text 1 -position {20 8} -alignment center -text {This static example reproduces figure 11-3
of "The OpenGL Programming Guide 3rd Edition" V 1.2}

set group [$w.zinc add group 1]

set g1 [$w.zinc add group $group]
set curve1 [$w.zinc add curve $g1 {}]
$w.zinc contour $curve1 add +1 { 0 0 0 120 120 120 120 0 0 0}
$w.zinc contour $curve1 add +1 { 20 20 20 100 100 100 100 20 20 20}
$w.zinc contour $curve1 add +1 { 40 40 40 80 80 80 80 40 40 40}
$w.zinc translate $g1 100 100


set g2 [$w.zinc add group $group]
set curve2 [$w.zinc add curve $g2 {}]
$w.zinc contour $curve2 add +1 { 0 0 0 120 120 120 120 0 0 0}
$w.zinc contour $curve2 add -1 { 20 20 20 100 100 100 100 20 20 20}
$w.zinc contour $curve2 add -1 { 40 40 40 80 80 80 80 40 40 40}
$w.zinc translate $g2 260 100


set g3 [$w.zinc add group $group]
set curve3 [$w.zinc add curve $g3 {}]
$w.zinc contour $curve3 add +1 { 20 0 20 120 100 120 100 0 20 0}
$w.zinc contour $curve3 add +1 { 40 20 60 120 80 20 40 20}
$w.zinc contour $curve3 add +1 { 0 60 0 80 120 80 120 60 0 60}
$w.zinc translate $g3 420 100

set g4 [$w.zinc add group $group]
set curve4 [$w.zinc add curve $g4 {}]
$w.zinc contour $curve4 add +1 { 0 0 0 140 140 140 140 60 60 60 60 80 80 80 80 40 40 40 40 100 100 100 100 20 20 20 20 120 120 120 120 0 0 0}
$w.zinc translate $g4 580 100

$w.zinc scale $group 0.6 0.6
$w.zinc translate $group 80 40

set t [$w.zinc add text $group -underlined yes -text "Contours"]
$w.zinc translate $t 280 30
set t [$w.zinc add text $group -underlined yes -text "-fillrule"]
$w.zinc translate $t -110 30
set dy 0
foreach fillrule {odd nonzero positive negative abs_geq_2} {
    set dy [expr $dy + 160]
    set t [$w.zinc add text $group -text $fillrule]
    $w.zinc translate $t -110 [expr 100+$dy]
    foreach item "$curve1 $curve2 $curve3 $curve4" {
	set clone [$w.zinc clone $item -fillrule $fillrule -filled 1]
	$w.zinc translate $clone 0 $dy
    }
}

# creating simple lines with arrows under each curves
foreach item "$curve1 $curve2 $curve3 $curve4" {
    set contour_number [$w.zinc contour $item]
    #puts "$item contour_number=$contour_number\n"
    for {set n 0} {$n <=[expr $contour_number-1]} {incr n} {
	set points [$w.zinc coords $item $n]
	set nbpoints [llength $points]
	for {set i 0} {$i <=[expr $nbpoints-2]} {incr i} {
	    set firstpoint [lindex $points $i]
	    set lastpoint [lindex $points [expr $i+1]]
	    set middlepoint "[expr [lindex $firstpoint 0]+([lindex $lastpoint 0]- [lindex $firstpoint 0])/1.5] [expr [lindex $firstpoint 1]+([lindex $lastpoint 1]-[lindex $firstpoint 1])/1.5]"
	    $w.zinc add curve [$w.zinc group $item] "$firstpoint $middlepoint" -lastend "7 10 4"
	}
    }
}