| Date: | 2015-09-29 15:51:08 (7 years 11 months ago) |
|---|---|
| Author: | Werner Almesberger |
| Commit: | 6800f025c17ac9a79a750a72765c61acda359fa9 |
| Message: | sl2/: standalone slicer (WIP) sfc/slicer.py has troubles with artefacts. It seems that we can do much better by avoiding the high-level operations and doing all the slicing "manually". |
| Files: |
sl2/README (1 diff) sl2/slicer.pl (1 diff) |
Change Details
| sl2/README | ||
|---|---|---|
| 1 | Yet another slicer. This one picks up the idea from sfc/slicer.py but | |
| 2 | implements it without using FreeCAD. The FreeCAD-based solution turned | |
| 3 | out to produce weird artefacts for some reason, e.g., open paths that | |
| 4 | were then falsely closed and yielded bogus toolpaths. | |
| 5 | ||
| 6 | This slicer uses very strict conditions for horizontality: all the | |
| 7 | points of a horizontal facet must have identical Z coordinates. It | |
| 8 | also implicitly ensures that all paths are closed. | |
| sl2/slicer.pl | ||
|---|---|---|
| 1 | #!/usr/bin/perl | |
| 2 | # | |
| 3 | # slicer.pl - Standalone STL to Gnuplot slicer | |
| 4 | # | |
| 5 | # Written 2015 by Werner Almesberger | |
| 6 | # Copyright 2015 by Werner Almesberger | |
| 7 | # | |
| 8 | # This program//library is free software; you can redistribute it and/or | |
| 9 | # modify it under the terms of the GNU Lesser General Public | |
| 10 | # License as published by the Free Software Foundation; either | |
| 11 | # version 2.1 of the License, or (at your option) any later version. | |
| 12 | # | |
| 13 | ||
| 14 | ||
| 15 | $epsilon = 0.0001; | |
| 16 | ||
| 17 | $flip = 1; | |
| 18 | ||
| 19 | ||
| 20 | $v_n = 0; | |
| 21 | $e_n = 0; | |
| 22 | while (<>) { | |
| 23 | if (/\bfacet/) { | |
| 24 | undef @f; | |
| 25 | next; | |
| 26 | } | |
| 27 | if (/endfacet/) { | |
| 28 | if ($f[2] == $f[5] && $f[2] == $f[8]) { | |
| 29 | $z_level{$f[2]} = 1; | |
| 30 | } else { | |
| 31 | push(@m, [ @f ]); | |
| 32 | } | |
| 33 | next; | |
| 34 | } | |
| 35 | if (/vertex\s+/) { | |
| 36 | my @tmp = split(/\s+/, $'); | |
| 37 | ||
| 38 | if ($flip) { | |
| 39 | push(@f, -$tmp[0], $tmp[1], -$tmp[2]); | |
| 40 | } else { | |
| 41 | push(@f, @tmp); | |
| 42 | } | |
| 43 | next; | |
| 44 | } | |
| 45 | } | |
| 46 | ||
| 47 | ||
| 48 | sub cut | |
| 49 | { | |
| 50 | local ($z, $a, $b, @f) = @_; | |
| 51 | ||
| 52 | if ($f[$a + 2] < $z &&$f[$b + 2] > $z) { | |
| 53 | my $dx = $f[$b] - $f[$a]; | |
| 54 | my $dy = $f[$b + 1] - $f[$a + 1]; | |
| 55 | my $dz = $f[$b + 2] - $f[$a + 2]; | |
| 56 | ||
| 57 | my $f = ($z - $f[$a + 2]) / $dz; | |
| 58 | return [ $dx * $f + $f[$a], $dy * $f + $f[$a + 1] ]; | |
| 59 | } | |
| 60 | if ($f[$a + 2] > $z &&$f[$b + 2] < $z) { | |
| 61 | return &cut($z, $b, $a, @f); | |
| 62 | } | |
| 63 | return (); | |
| 64 | } | |
| 65 | ||
| 66 | ||
| 67 | sub remove | |
| 68 | { | |
| 69 | local ($a, $b) = @_; | |
| 70 | ||
| 71 | #print STDERR "\tremove $b from $a (", join(",", @{ $next{$a} }), "\n"; | |
| 72 | my @tmp = grep($_ ne $b, @{ $next{$a} }); | |
| 73 | if ($#tmp == -1) { | |
| 74 | delete $next{$a}; | |
| 75 | } else { | |
| 76 | $next{$a} = [ @tmp ]; | |
| 77 | } | |
| 78 | } | |
| 79 | ||
| 80 | ||
| 81 | for $level (sort keys %z_level) { | |
| 82 | my $z = $level + $epsilon; | |
| 83 | ||
| 84 | # print STDERR "level = $level\n"; | |
| 85 | undef %next; | |
| 86 | for (@m) { | |
| 87 | my @f = @{ $_ }; | |
| 88 | my @p = &cut($z, 0, 3, @f); | |
| 89 | push(@p, &cut($z, 0, 6, @f)); | |
| 90 | push(@p, &cut($z, 3, 6, @f)); | |
| 91 | ||
| 92 | next if $#p < 1; | |
| 93 | die "BAD $#p" if $#p > 1; | |
| 94 | ||
| 95 | my $a = "$p[0][0] $p[0][1]"; | |
| 96 | my $b = "$p[1][0] $p[1][1]"; | |
| 97 | push(@{ $next{$a} }, $b); | |
| 98 | push(@{ $next{$b} }, $a); | |
| 99 | # print STDERR "$z: ($a) to ($b)\n"; | |
| 100 | } | |
| 101 | ||
| 102 | while (1) { | |
| 103 | my @k = keys %next; | |
| 104 | ||
| 105 | last if $#k == -1; | |
| 106 | my $p0 = $k[0]; | |
| 107 | $p = $p0; | |
| 108 | while (1) { | |
| 109 | my $next = $next{$p}[0]; | |
| 110 | ||
| 111 | print "$p $z\n"; | |
| 112 | # print STDERR "at $p\n"; | |
| 113 | # print STDERR "\tnext $next\n"; | |
| 114 | die "open path" unless defined $next; | |
| 115 | &remove($p, $next); | |
| 116 | &remove($next, $p); | |
| 117 | last if $p0 eq $next; | |
| 118 | $p = $next; | |
| 119 | } | |
| 120 | print "$p0 $z\n"; | |
| 121 | print "\n"; | |
| 122 | } | |
| 123 | } | |
Branches:
master
