our $fa = 10;
-our @triangles;
+our $triangles;
+our $output;
sub shift_arg () {
die unless @ARGV;
scalar shift @ARGV;
}
+#no warnings qw(recursion);
+
sub subdivide_triangle ($$) {
my ($t, $fn) = @_;
+
+ #print STDERR 'SUBDIV', Dumper($t, $fn);
+
my @mids;
foreach my $ix (0..2) {
my $jx = ($ix+1) % 3;
foreach my $ci (0..2) {
push @midp, 0.5 * ($t->[$ix][$ci] + $t->[$jx][$ci]);
}
- push @mids, @midp;
+ push @mids, \@midp;
}
foreach my $ix (0..2) {
+ #print STDERR 'SUBDIV IX ', $ix, "\n";
my $kx = ($ix+2) % 3;
- $fn->([ $t->[$ix], $mids[$ix], $t->[$kx] ]);
+ $fn->([ $t->[$ix], $mids[$ix], $mids[$kx] ]);
}
+ #print STDERR 'SUBDIV MID\n';
$fn->(\@mids);
}
+sub append_triangle ($) {
+ my ($t) = @_;
+ push @$output, $t;
+}
+
#---------- project-cylinder ----------
our $project_cylinder_radius;
our $project_cylinder_max_d_theta;
+sub project_cylinder_need_subdivide () {
+ foreach my $t (@$triangles) {
+ my @thetas = map { $_->[0] / $project_cylinder_radius } @$t;
+
+ foreach my $ix (0..2) {
+ if (abs($thetas[$ix] - $thetas[($ix+1)%3])
+ > $project_cylinder_max_d_theta) {
+ return 1;
+ }
+ }
+ }
+ return 0;
+}
+
sub project_cylinder_tri {
my ($t) = @_;
- my $radius = $project_cylinder_radius;
-
- my @thetas = map { $_->[0] / $radius } @$t;
+ #print STDERR 'PROJECT', Dumper($t);
- foreach my $ix (0..2) {
- if (abs($thetas[$ix] - $thetas[($ix+1)%3])
- > $project_cylinder_max_d_theta) {
- subdivide_triangle $t, \&project_cylinder_tri;
- return;
- }
- }
+ my $radius = $project_cylinder_radius;
my @ot;
- foreach my $p ($t) {
+ foreach my $p (@$t) {
my ($x,$y,$z) = @$p;
my $r = $radius - $y;
my $theta = $x / $radius;
-$r * cos($theta),
$z ];
}
- push @triangles, \@ot;
+ append_triangle \@ot;
}
sub op__project_cylinder () {
$project_cylinder_radius = shift_arg;
$project_cylinder_max_d_theta = $fa * TAU/360;
- my @input = (@triangles);
- @triangles = ();
+ while (project_cylinder_need_subdivide()) {
+ $output = [];
+ foreach my $t (@$triangles) {
+ subdivide_triangle $t, \&append_triangle;
+ }
+ $triangles = $output;
+ }
- project_cylinder_tri $_ foreach @input;
+ $output = [];
+ foreach my $t (@$triangles) {
+ project_cylinder_tri $t;
+ }
+ $triangles = $output;
}
#---------- main program ----------
push @$triangle, \@xyz;
} elsif (m/^endloop/) {
die unless @$triangle == 3;
- push @triangles, $triangle;
+ push @$triangles, $triangle;
undef $triangle;
} elsif (m/^(?:solid|facet\s+normal|endfacet|endsolid)\s/) {
} else {
print "solid distort-stl\n";
-foreach my $t (@triangles) {
+foreach my $t (@$triangles) {
print " facet normal 0 0 0\n";
print " outer loop\n";
+ die unless @$t==3;
foreach my $p (@$t) {
+ die unless @$p==3;
print " vertex";
printf " %.18g", $_ foreach @$p;
print "\n";