#!/bin/sh
. ./Common

###############################################################################

tst "outer offset" <<EOF
struct p2d *p = p2d_new();
struct p2d *q;

p2d_append(p, v2d_new(0, 0));
p2d_append(p, v2d_new(2, 0));
p2d_append(p, v2d_new(2, 1));
p2d_append(p, v2d_new(0, 1));
p2d_close(p);
q = p2d_offset(p, 0.5);
p2d_write_gnuplot(stdout, p2d_reverse(q->next));
EOF

expect <<EOF
-0.5 -0.5
2.5 -0.5
2.5 1.5
-0.5 1.5
-0.5 -0.5

EOF

#------------------------------------------------------------------------------

tst "inner offset" <<EOF
struct p2d *p = p2d_new();
struct p2d *q;

p2d_append(p, v2d_new(0, 0));
p2d_append(p, v2d_new(2, 0));
p2d_append(p, v2d_new(2, 1));
p2d_append(p, v2d_new(0, 1));
p2d_close(p);
q = p2d_offset(p, -0.1);
p2d_write_gnuplot(stdout, q);
EOF

expect <<EOF
0.1 0.1
1.9 0.1
1.9 0.9
0.1 0.9
0.1 0.1

EOF

#------------------------------------------------------------------------------

tst "inner offset, polygon cw" <<EOF
struct p2d *p = p2d_new();
struct p2d *q;

p2d_append(p, v2d_new(0, 0));
p2d_append(p, v2d_new(0, 1));
p2d_append(p, v2d_new(2, 1));
p2d_append(p, v2d_new(2, 0));
p2d_close(p);
q = p2d_offset(p, -0.1);
p2d_write_gnuplot(stdout, q);
EOF

expect <<EOF
0.1 0.1
1.9 0.1
1.9 0.9
0.1 0.9
0.1 0.1

EOF

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