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
|
#! /usr/bin/perl
# This short script creates fixed look-up tables for xcftools
# Copyright (C) 2006 Henning Makholm
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of version 2 of the GNU General Public License as
# published by the Free Software Foundation.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
use strict ; use warnings ;
sub shipsubarray (@) {
while( @_ > 1 && $_[$#_] == 0 ) {
pop @_ ;
}
my $last = pop @_ ;
print " {" ;
my $left = 75 ;
for my $d ( (map{ $_ . "," } @_), "$last}," ) {
if( length($d) > $left ) {
print "\n " ;
$left = 75 ;
}
print $d ;
$left -= length($d) ;
}
print "\n" ;
}
my $precompute_it = 1 ;
if( open CONFIGH, "<", "config.h" ) {
$precompute_it = 0 ;
while( <CONFIGH> ) {
if( /\#\s*define\s+PRECOMPUTED_SCALETABLE/ ) {
$precompute_it = 1 ;
last ;
}
}
close CONFIGH ;
}
print "/* Autogenerated by $0 */\n" ;
print "#include \"pixels.h\"\n" ;
print "#ifdef PRECOMPUTED_SCALETABLE\n" ;
if( $precompute_it ) {
print "const uint8_t scaletable[256][256] = {\n" ;
for my $p ( 0..255 ) {
shipsubarray( map { int(($p*$_+127)/255) } ( 0 .. 255 ) );
# This formula has the property that
# scaletable[p][q] + scaletable[255-p][q] == q
# for all uint8_t values of p and q.
# This is important in order that a partially transparent
# pixel does not change the color of the underlying pixel
# unless the two pixels have different colors.
}
print "};\n" ;
} else {
print "#error PRECOMPUTED_SCALETABLE was not defined at generation time\n";
}
print "#endif\n" ;
if(0) {
print "const uint8_t divtable[256][256] = {\n" ;
for my $p ( 0..255 ) {
shipsubarray( map { $_ >= $p ? 255 : int(0.5 + 255*$_/$p) }
( 0 .. 255 ) );
}
print "};\n" ;
}
print "const rgba graytable[256] = {\n" ;
for my $p ( 0..255 ) {
print " (rgba)$p << RED_SHIFT | (rgba)$p << GREEN_SHIFT | (rgba)$p << BLUE_SHIFT,\n" ;
}
print "};\n" ;
|