aboutsummaryrefslogtreecommitdiff
path: root/Perl/demos/Tk/demos/zinc_lib/curve_bezier.pl
blob: ffa6061946d7ae60597f24d9d0056ee8f1acb63b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
#!/usr/bin/perl -w
# $Id: curve_bezier.pl 1550 2004-09-21 12:45:38Z mertz $
# This simple demo has been developped by C. Mertz <mertz@cena.fr>

####### This file has been initially inspired from svg examples

package curveBezier;

use vars qw( $VERSION );
($VERSION) = sprintf("%d.%02d", q$Revision: 1550 $ =~ /(\d+)\.(\d+)/);

use Tk::Zinc;


my $mw = MainWindow->new();
$mw->title('example of curves with cubic control points');

my $text = $mw->Text (-relief => 'sunken', -borderwidth => 2,
		      -setgrid => 'true',  -height =>3);
$text->pack(qw/-expand yes -fill both/);

$text->insert('0.0',
'6 examples of curves containing control points are displayed, 
 with the list of control points written just below.
You can move the handles to modify the bezier curves');


my $zinc = $mw->Zinc(-width => 700, -height => 650,
		     -font => "10x20",
		     -font => "9x15",
		     -borderwidth => 0,
                     -backcolor => "white",
		     -forecolor => "grey80",
		     -render => 1, # this demo also works without openGL
		     # with openGL, antialiasing makes the curves nicer
		      )->pack;

my $group = $zinc->add('group', 1);

$zinc->add('text',$group, -position => [50,20], -anchor => 'w',
	   -text => "Examples of curve items using cubic bezier control points",
	   -color => "grey20");

## Please note: much of the following items below could be computed
$zinc->add('text',$group, -position => [25,270], -anchor => 'w', -tags => ['bezier1'], -color => "grey20");
$zinc->add('curve',$group,[100, 200, 100, 100], -tags => ['line1', 'l1-2'], -linecolor => "#888888", -filled => 0, -linewidth => 2);
$zinc->add('curve',$group,[400, 100, 400, 200], -tags => ['line1', 'l3-4'], -linecolor => "#888888", -filled => 0, -linewidth => 2);
$zinc->add('curve',$group,[[100, 200], [100, 100, 'c'], [400, 100, 'c'], [400, 200]],
	   -tags => ['bezier1'], -closed => 0, -linecolor => "red", -linewidth => 5);
$zinc->add('arc',$group,[90, 190, 110, 210], -tags => ['handle1',"p1"], -filled => 1, -fillcolor => "#BBBBBB");
$zinc->add('arc',$group,[90, 90, 110, 110], -tags => ['handle1',"p2"], -filled => 1, -linewidth => 0, -fillcolor => "grey80", -filled => 1);
$zinc->add('arc',$group,[390, 90, 410, 110], -tags => ['handle1',"p3"], -filled => 1, -linewidth => 0, -fillcolor => "grey80", -filled => 1);
$zinc->add('arc',$group,[390, 190, 410, 210], -tags => ['handle1',"p4"], -filled => 1, -fillcolor => "#BBBBBB");

$zinc->add('text',$group, -position => [570,270], -anchor => 'w', -tags => ['bezier2'], -color => "grey20");
$zinc->add('curve',$group,[600, 200, 675, 100], -tags => ['line2', 'l1-2'], -linecolor => "#888888", -linewidth => 2);
$zinc->add('curve',$group,[975, 100, 900, 200], -tags => ['line2', 'l3-4'], -linecolor => "#888888", -linewidth => 2);
$zinc->add('curve',$group,[[600, 200], [675, 100, 'c'], [975, 100, 'c'], [900, 200]],
	   -tags => ['bezier2'], -closed => 0, -linecolor => "red", -linewidth => 5);
$zinc->add('arc',$group,[590, 190, 610, 210], -tags => ['handle2',"p1"], -filled => 1, -linecolor => "grey80", -linewidth => 2);
$zinc->add('arc',$group,[665, 90, 685, 110], -tags => ['handle2',"p2"], -filled => 1, -linewidth => 0, -fillcolor => "grey80");
$zinc->add('arc',$group,[965, 90, 985, 110], -tags => ['handle2',"p3"], -filled => 1, -linewidth => 0, -fillcolor => "grey80");
$zinc->add('arc',$group,[890, 190, 910, 210], -tags => ['handle2',"p4"], -filled => 1, -linecolor => "grey80", -linewidth => 2);

$zinc->add('text',$group, -position => [25,570], -anchor => 'w', -tags => ['bezier3'], -color => "grey20");
$zinc->add('curve',$group,[100, 500, 25, 400], -tags => ['line3', 'l1-2'], -linecolor => "#888888", -linewidth => 2);
$zinc->add('curve',$group,[475, 400, 400, 500], -tags => ['line3', 'l3-4'], -linecolor => "#888888", -linewidth => 2);
$zinc->add('curve',$group,[[100, 500], [25, 400, 'c'], [475, 400, 'c'], [400, 500]],
	   -tags => ['bezier3'], -closed => 0, -linecolor => "red", -linewidth => 5);
$zinc->add('arc',$group,[90, 490, 110, 510], -tags => ['handle3',"p1"], -filled => 1, -linecolor => "grey80", -linewidth => 2);
$zinc->add('arc',$group,[15, 390, 35, 410], -tags => ['handle3',"p2"], -filled => 1, -linewidth => 0, -fillcolor => "grey80", );
$zinc->add('arc',$group,[465, 390, 485, 410], -tags => ['handle3',"p3"], -filled => 1, -linewidth => 0, -fillcolor => "grey80", );
$zinc->add('arc',$group,[390, 490, 410, 510], -tags => ['handle3',"p4"], -filled => 1, -linecolor => "grey80", -linewidth => 2);

$zinc->add('text',$group, -position => [570,570], -anchor => 'w', -tags => ['bezier4'], -color => "grey20");
$zinc->add('curve',$group,[600, 500, 600, 350], -tags => ['line4', 'l1-2'], -linecolor => "#888888", -linewidth => 2);
$zinc->add('curve',$group,[900, 650, 900, 500], -tags => ['line4', 'l3-4'], -linecolor => "#888888", -linewidth => 2);
$zinc->add('curve',$group,[[600, 500], [600, 350, 'c'], [900, 650, 'c'], [900, 500]], -tags => ['bezier4'], -closed => 0, -linecolor => "red", -linewidth => 5);
$zinc->add('arc',$group,[590, 490, 610, 510], -tags => ['handle4',"p1"], -filled => 1, -linecolor => "grey80", -linewidth => 2);
$zinc->add('arc',$group,[590, 340, 610, 360], -tags => ['handle4',"p2"], -filled => 1, -linewidth => 0, -fillcolor => "grey80");
$zinc->add('arc',$group,[890, 640, 910, 660], -tags => ['handle4',"p3"], -filled => 1, -linewidth => 0, -fillcolor => "grey80");
$zinc->add('arc',$group,[890, 490, 910, 510], -tags => ['handle4',"p4"], -filled => 1, -linecolor => "grey80", -linewidth => 2);

$zinc->add('text',$group, -position => [25,870], -anchor => 'w', -tags => ['bezier5'], -color => "grey20");
$zinc->add('curve',$group,[100, 800, 175, 700], -tags => ['line5', 'l1-2'], -linecolor => "#888888", -filled => 0, -linewidth => 2);
$zinc->add('curve',$group,[325, 700, 400, 800], -tags => ['line5', 'l3-4'], -linecolor => "#888888", -filled => 0, -linewidth => 2);
$zinc->add('curve',$group,[[100, 800], [175, 700, 'c'], [325, 700, 'c'], [400, 800]],
	   -tags => ['bezier5'], -closed => 0, -linecolor => "red", -linewidth => 5);
$zinc->add('arc',$group,[90, 790, 110, 810], -tags => ['handle5',"p1"], -filled => 1, -linecolor => "grey80", -linewidth => 2);
$zinc->add('arc',$group,[165, 690, 185, 710], -tags => ['handle5',"p2"], -filled => 1, -linewidth => 0, -fillcolor => "grey80", -filled => 1);
$zinc->add('arc',$group,[315, 690, 335, 710], -tags => ['handle5',"p3"], -filled => 1, -linewidth => 0, -fillcolor => "grey80", -filled => 1);
$zinc->add('arc',$group,[390, 790, 410, 810], -tags => ['handle5',"p4"], -filled => 1, -linecolor => "grey80", -linewidth => 2);

$zinc->add('text',$group, -position => [570,980], -anchor => 'w', -tags => ['bezier6'], -color => "grey20");
$zinc->add('curve',$group,[600, 800, 625, 700], -tags => ['line6', 'l1-2'], -linecolor => "#888888", -linewidth => 2);
$zinc->add('curve',$group,[725, 700, 750, 800], -tags => ['line6', 'l3-4'], -linecolor => "#888888", -linewidth => 2);
$zinc->add('curve',$group,[750, 800, 775, 900], -tags => ['line6', 'l4-5'], -linecolor => "#888888", -linewidth => 2);
$zinc->add('curve',$group,[875, 900, 900, 800], -tags => ['line6', 'l6-7'], -linecolor => "#888888", -linewidth => 2);
$zinc->add('curve',$group,[[600, 800], [625, 700, 'c'], [725, 700, 'c'], [750, 800], [775, 900, 'c'], [875, 900, 'c'], [900, 800]],
	   -tags => ['bezier6'], -filled => 0, -closed => 0, -linecolor => "red", -linewidth => 5);
$zinc->add('arc',$group,[590, 790, 610, 810], -tags => ['handle6',"p1"], -filled => 1, -linecolor => "grey80", -linewidth => 2);
$zinc->add('arc',$group,[615, 690, 635, 710], -tags => ['handle6',"p2"], -filled => 1, -linewidth => 0, -fillcolor => "grey80");
$zinc->add('arc',$group,[715, 690, 735, 710], -tags => ['handle6',"p3"], -filled => 1, -linewidth => 0, -fillcolor => "grey80");
$zinc->add('arc',$group,[740, 790, 760, 810], -tags => ['handle6',"p4"], -filled => 1, -linecolor => "blue",-fillcolor => "blue", -linewidth => 2);
$zinc->add('arc',$group,[766, 891, 784, 909], -tags => ['handle6',"p5"], -filled => 1, -linecolor => "grey80", -linewidth => 4);
$zinc->add('arc',$group,[865, 890, 885, 910], -tags => ['handle6',"p6"], -filled => 1, -linewidth => 0, -fillcolor => "grey80");
$zinc->add('arc',$group,[890, 790, 910, 810], -tags => ['handle6',"p7"], -filled => 1, -linecolor => "grey80", -linewidth => 2);

$zinc->scale($group, 0.6, 0.6);

## Set the text of the text item with a tag "tag"
## to a human-readable form of the coords of the
## corresponding curve with the same tag "tag"
sub setText {
    my ($tag) = @_;
    my $textItem = $zinc->find("withtype", 'text', $tag);
    my $curveItem = $zinc->find("withtype", 'curve', $tag);
    my @coords = $zinc->coords($curveItem);
    my $count = 0;
    my $text = "[ ";
    while (@coords) {
	$refXYc = pop @coords;
	my $x=sprintf "%i", $refXYc->[0];
	my $y=sprintf "%i", $refXYc->[1];
	my $t=$refXYc->[2];
	$t = (defined $t) ? ", '".$t."'" : "" ;
	$text .= "[$x, $y$t]";
	if (@coords) { $text .= ", "; }
	if ($count and @coords) {
	    $text .= "\n   ";
	    $count =0;
	} else {
	    $count++;
	}
    }
    $text .= " ]";
    $zinc->itemconfigure($textItem, -text => $text);
}

foreach my $bezierCount (1..6) {
    &setText ("bezier".$bezierCount);
    my $curveItem = $zinc->find("withtype", 'curve', "bezier".$bezierCount);
    my @coords = $zinc->coords($curveItem);
#    print "$bezierCount : ", scalar @coords, "\n";
    $zinc->bind("handle$bezierCount", '<ButtonPress-1>', [\&press, \&motion]);
    $zinc->bind("handle$bezierCount", '<ButtonRelease-1>', [\&release]);
}



&Tk::MainLoop;


##### bindings for moving the handles
my ($cur_x, $cur_y,$item, $bezierNum, $ptNum);
sub press {
    my ($zinc, $action) = @_;
    my $ev = $zinc->XEvent();
    $cur_x = $ev->x;
    $cur_y = $ev->y;
    $item = $zinc->find('withtag', 'current');
    $zinc->bind($item, '<Motion>', [$action]);
    foreach ( $zinc->gettags($item) ) {
	## looking for the tag "handlei"
	if ( /^handle(\d+)$/ ) {
	    $bezierNum = $1;
	}
	## looking for the tag "pj"
	if ( /^p(\d+)$/ ) {
	    $ptNum = $1;
	}
    }
#    print "bezierNum=$bezierNum ptNum=$ptNum\n";
}

sub motion {
    my ($zinc) = @_;
    my $ev = $zinc->XEvent();
    my $lx = $ev->x;
    my $ly = $ev->y;
    my ($dx,$dy) = $zinc->transform($group, [$lx-$cur_x, $ly-$cur_y]);
    &moveHandle($item,$dx,$dy);
    my ($pt1,$pt2) = $zinc->coords($item);
#    print "coords=",@{$pt1}, " ",@{$pt2},"\n";
    $cur_x = $lx;
    $cur_y = $ly;
}

sub release {
    my ($zinc) = @_;
    $zinc->bind($item,'<Motion>', '');
    $item = "";
}

sub moveHandle {
    my ($item,$dx,$dy) = @_;
    my ($pt1,$pt2) = $zinc->coords($item);
    ## modifying the handle coords
    $zinc->coords($item, [ $pt1->[0]+$dx, $pt1->[1]+$dy, $pt2->[0]+$dx, $pt2->[1]+$dy]);
    my $prevPtNum = $ptNum-1;
    # there should only be one such item!
    my $lineA = $zinc->find("withtag", "line$bezierNum && l$prevPtNum-$ptNum");
    if (defined $lineA) {
	my ($x,$y) = $zinc->coords($lineA,0,1); # to get the 2nd point coords
	$zinc->coords($lineA, 0,1, [ $x+$dx, $y+$dy ]);
    }

    my $nextPtNum = $ptNum+1;
    # there should only be one such item:
    my ($lineB) = $zinc->find("withtag", "line$bezierNum && l$ptNum-$nextPtNum");
    if (defined $lineB) {
	my ($x,$y) = $zinc->coords($lineB,0,0); # to get the 1st point coords
	$zinc->coords($lineB, 0,0, [ $x+$dx, $y+$dy ] );
    }

    my ($x,$y,$control) = $zinc->coords("bezier$bezierNum", 0,$ptNum-1);
    $zinc->coords("bezier$bezierNum", 0,$ptNum-1, [ [$x+$dx, $y+$dy, $control] ] );
    &setText ("bezier$bezierNum");
	
}