distort-stl: new approach

diff --git a/distort-stl b/distort-stl
index 4820e03104d51485c3d7b00a9b3f945aa1f05961..eb3a7a15deb92a6c393b45fd3db21f63426cab00 100755 (executable)
--- a/distort-stl
+++ b/distort-stl
@@ -18,27 +18,87 @@
 #       polar-rectangular coords:
 #          Z' = Z; R' = Y + RADIUS; theta' = X / RADIUS
 #       and then converts back into cartesian
 #       polar-rectangular coords:
 #          Z' = Z; R' = Y + RADIUS; theta' = X / RADIUS
 #       and then converts back into cartesian

+#       honours fa but not fs or fn
+#
+#   set-fa $FA

 
 use strict;
 use autodie;
 
 use File::Temp;
 
 use strict;
 use autodie;
 
 use File::Temp;

+use List::Util;
+
+our $fa = 10;
+
+our @triangles;

 
 sub shift_arg () {
     die unless @ARGV;
     scalar shift @ARGV;
 }
 
 
 sub shift_arg () {
     die unless @ARGV;
     scalar shift @ARGV;
 }
 

-sub pointmap_project_cylinder {
-    my ($x,$y,$z) = @_;
-    my $radius = shift_arg;
-    my $r = $radius - $y;
-    my $theta = $x / $radius;
-    return ($r * sin($theta),
-           -$r * cos($theta),
-           $z);
+sub subdivide_triangle ($$) {
+    my ($it, $fn) = @_;
+    my @mids;
+    foreach my $ix (0..2) {
+       my $jx = ($ix+1) % 3;
+       my @midp;
+       foreach my $ci (0..2) {
+           push @midp, 0.5 * ($it->[$ix][$ci] + $it->[$jx][$ci]);
+       }
+       push @mids, @midp;
+    }
+    foreach my $ix (0..2) {
+       my $kx = ($ix+2) % 3;
+       $fn->([ $it->[$ix], $mids[$ix], $it->[$kx] ]);
+    }
+    $fn->(\@mids);
+}
+
+#---------- project-cylinder ----------
+
+our $project_cylinder_radius;
+our $project_cylinder_max_d_theta;
+
+sub project_cylinder_tri {
+    my ($it) = @_;
+
+    my $radius = project_cylinder_radius;
+
+    my @thetas = map { $_->[0] / $radius } @$it;
+
+    foreach my $ix (0..2) {
+       if (abs($thetas[$ix] - $thetas[($ix+1)%3])
+           > $project_cylinder_max_d_theta) {
+           subdivide_triangle $it, \&project_cylinder_tri;
+           return;
+       }
+    }
+
+    my @ot;
+    foreach my $p (@it) {
+       my ($x,$y,$z) = @$p;
+       my $r = $radius - $y;
+       my $theta = $x / $radius;
+       push @ot, [ $r * sin($theta),
+                   -$r * cos($theta),
+                   $z ];
+    }
+    push @triangles, \@ot;
+}
+
+sub op__project_cylinder () {
+    $project_cylinder_radius = shift_arg;
+    $project_cylinder_max_d_theta = $fa * TAU/360;
+
+    my @input = (@triangles);
+    @triangles = ();
+
+    project_cylinder_tri $_ foreach @input;

 }
 
 }
 

+#---------- main program ----------
+

 if (@ARGV && $ARGV[0] =~ m/^-/) {
     die "no options supported\n";
 }
 if (@ARGV && $ARGV[0] =~ m/^-/) {
     die "no options supported\n";
 }


@@ -52,28 +112,52 @@ my $admesh_stdout = '--write-ascii-stl /dev/fd/3 3>&1 >/dev/null';
 
 open I, "admesh $admesh_stdout $itmp |";
 
 
 open I, "admesh $admesh_stdout $itmp |";
 

-our @saved_argv = @ARGV;
+my $triangle;

 
 while (<I>) {
 
 while (<I>) {

-    @ARGV = @saved_argv;
-    if (s/^\s+vertex\s+//) {
+    if (m/^\s+outer\s+loop/) {
+       die if $triangle;
+       $triangle = [];
+    } elsif (s/^\s+vertex\s+//) {

        my $lhs = $&;
        s/\s+$//;
        my @xyz = split /\s+/, $_;
        my $lhs = $&;
        s/\s+$//;
        my @xyz = split /\s+/, $_;

-       while (@ARGV) {
-           my $op = shift_arg;
-           $op =~ y/-/_/;
-           @xyz = &{ ${*::}{"pointmap_$op"} }( @xyz );
-       }
-       @xyz = map { sprintf "%.18g", $_ } @xyz;
-       $_ = "$lhs@xyz\n";
+       die unless $triangle;
+       push @$triangle, \@xya;
+    } elsif (m/^\s+endloop/) {
+       die unless @$triangle == 3;
+       push @triangles, $triangle;
+    } elsif (m/^\s+(?:solid|facet\s+normal|endfacet|endsolid)\s/) {
+    } else {
+       die "$_ ?";

     }
     }

-    print $otmp $_;

 }
 
 close I;
 <I> if 0; # suppresses Name "main::I" used only once
 
 }
 
 close I;
 <I> if 0; # suppresses Name "main::I" used only once
 

+while (@ARGV) {
+    my $op = shift_arg;
+    $op =~ y/-/_/;
+    &{ ${*::}{"op__$op"} };
+}
+
+select $otmp;
+
+print "solid distort-stl\n";
+
+foreach my $t (@triangles) {
+    print "  facet normal 0 0 0\n";
+    print "    outer loop\n";
+    print "      vertex";
+    printf " %.18g", $_ foreach @$t;
+    print "\n";
+    print "    endloop\n";
+    print "  endfacet\n";
+}
+
+print "endsolid distort-stl\n";
+

 flush $otmp;
 
 system "admesh --normal-values $admesh_stdout $otmp";
 flush $otmp;
 
 system "admesh --normal-values $admesh_stdout $otmp";