X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=reprap-play.git;a=blobdiff_plain;f=distort-stl;h=68290c410a6ae4738d680d6409abd8f3464c008e;hp=68b7e28d79fa731b05cb6d9205319ab8b819db57;hb=f1824fce4c0b4420e0ba377d8d8a4e43e42e4a7d;hpb=6562f4b2558c850a0c98b71971b2569b401d4a95

diff --git a/distort-stl b/distort-stl
index 68b7e28..68290c4 100755
--- a/distort-stl
+++ b/distort-stl
@@ -32,6 +32,14 @@ use Data::Dumper;
 
 sub TAU () { M_PI * 2; }
 
+our $debug = $ENV{DISTORT_DEBUG} // 0 ;
+
+my $ps = $ENV{DISTORT_PS};
+if ($ps) {
+    open PS, "> $ps" or die $!;
+    print PS "%!\n";
+}
+
 our $fa = 10;
 
 our $triangles;
@@ -47,6 +55,22 @@ sub shift_arg () {
 sub sprintf_triangle ($) {
     my ($t) = @_;
 
+    return '' unless $debug;
+
+    if ($ps && $t->[3] =~ m/$ENV{DISTORT_PS_RE}/) {
+	printf PS <<'END',
+ %20.16g %20.16g %20.16g moveto
+ %20.16g %20.16g %20.16g lineto
+ %20.16g %20.16g %20.16g lineto
+ closepath stroke
+END
+		$t->[0][0], $t->[0][1], $t->[0][2],
+		$t->[1][0], $t->[1][1], $t->[1][2],
+		$t->[2][0], $t->[2][1], $t->[2][2],
+		or die $!;
+	flush PS or die $!;
+    }
+
     sprintf
 	"%11.6f,%11.6f,%11.6f / ".
 	"%11.6f,%11.6f,%11.6f / ".
@@ -60,42 +84,59 @@ sub sprintf_triangle ($) {
 sub maybe_subdivide_triangle ($$$$) {
     my ($t, $ok, $changed, $edge_need_subdivide_fn) = @_;
 
-    print STDERR sprintf_triangle $t;
-    
-    foreach my $ix (0..2) {
-	my $jx = ($ix+1) % 3;
-	my $kx = ($ix+2) % 3;
-	if ($edge_need_subdivide_fn->($t->[$ix], $t->[$jx])) {
-	    printf STDERR
-		" S i=%d j=%d k=%d ",
-		$ix, $jx, $kx;
-	    my @midp;
-	    foreach my $ci (0..2) {
-		push @midp, 0.5 * ($t->[$ix][$ci] + $t->[$jx][$ci]);
-	    }
-
-	    printf STDERR
-		" midp %11.6f,%11.6f,%11.6f\n",
-		@midp;
-
-	    # triangle i-j-k, splitting edge i-m
-	    # gives    i-m-k, k-m-j
-	    my $n = [ @$t ]; $n->[$ix] = \@midp;  $n->[3] = "$t->[3]a$ix$jx";
-	    unshift @$changed, $n;
-
-	    printf STDERR "%s\n", sprintf_triangle $n;
-
-	    my $n = [ @$t ]; $n->[$jx] = \@midp;  $n->[3] = "$t->[3]b$ix$jx";
-	    unshift @$changed, $n;
+    print STDERR sprintf_triangle $t if $debug;
 
-	    printf STDERR "%s\n", sprintf_triangle $n;
+    my (@longest) = qw(-1);
 
-	    return;
+    foreach my $ix (0..2) {
+	my $jx = ($ix+1) % 3;
+	next unless $edge_need_subdivide_fn->($t->[$ix], $t->[$jx]);
+	my $l2 = 0;
+	foreach my $ci (0..2) {
+	    my $d = $t->[$ix][$ci] - $t->[$jx][$ci];
+	    $l2 += $d*$d;
 	}
+	next unless $l2 > $longest[0];
+	@longest = ($l2, $ix, $jx);
+    }
+    if ($longest[0] < 0) {
+	push @$ok, $t;
+	printf STDERR "OK nok=%d nchanged=%d\n",
+	    (scalar @$ok), (scalar @$changed)
+	    if $debug;
+	print STDERR Dumper(\@$ok) if $debug>=2;
+	return;
     }
-    push @$ok, $t;
-    printf STDERR "OK nok=%d nchanged=%d\n",
-	(scalar @$ok), (scalar @$changed);
+    my ($dummy,$ix,$jx) = @longest;
+    my $kx = ($ix+2) % 3;
+
+    printf STDERR
+	" S i=%d j=%d k=%d ",
+	$ix, $jx, $kx
+	if $debug;
+    my @midp;
+    foreach my $ci (0..2) {
+	push @midp, 0.5 * ($t->[$ix][$ci] + $t->[$jx][$ci]);
+    }
+
+    printf STDERR
+	" midp %11.6f,%11.6f,%11.6f\n",
+	@midp
+	if $debug;
+
+    # triangle i-j-k, splitting edge i-m
+    # gives    i-m-k, k-m-j
+    my $gensplit = sub {
+	my ($ixjx, $xwhat) = @_;
+	my $n = [ @$t ];
+	$n->[$ixjx] = \@midp;
+	$n->[3] = "$t->[3]$xwhat";
+	printf STDERR "%s\n", sprintf_triangle $n if $debug;
+	unshift @$changed, $n;
+    };
+    $gensplit->($ix, "a$ix$jx");
+    $gensplit->($jx, "b$ix$jx");
+    return;
 }
 
 sub maybe_subdivide ($) {
@@ -139,7 +180,7 @@ sub project_cylinder_tri {
     my $radius = $project_cylinder_radius;
 
     my @ot;
-    foreach my $p (@$t) {
+    foreach my $p (@$t[0..2]) {
 	my ($x,$y,$z) = @$p;
 	my $r = $radius - $y;
 	my $theta = $x / $radius;
@@ -147,6 +188,7 @@ sub project_cylinder_tri {
 		    -$r * cos($theta),
 		    $z ];
     }
+    push @ot, $t->[3].'P';
     append_triangle \@ot;
 }
 
@@ -234,8 +276,8 @@ print "solid distort-stl\n";
 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 @$t==4;
+    foreach my $p (@$t[0..2]) {
 	die unless @$p==3;
 	print "      vertex";
 	printf " %.18g", $_ foreach @$p;