From d7e9d913730b96a83751863ad896648488296532 Mon Sep 17 00:00:00 2001 From: Tavian Barnes Date: Sat, 6 Nov 2010 16:57:33 -0400 Subject: Add pattern framework, impelement checker pattern. --- libdimension/checker.c | 58 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 58 insertions(+) create mode 100644 libdimension/checker.c (limited to 'libdimension/checker.c') diff --git a/libdimension/checker.c b/libdimension/checker.c new file mode 100644 index 0000000..9c1de34 --- /dev/null +++ b/libdimension/checker.c @@ -0,0 +1,58 @@ +/************************************************************************* + * Copyright (C) 2010 Tavian Barnes * + * * + * This file is part of The Dimension Library. * + * * + * The Dimension Library is free software; you can redistribute it and/ * + * or modify it under the terms of the GNU Lesser General Public License * + * as published by the Free Software Foundation; either version 3 of the * + * License, or (at your option) any later version. * + * * + * The Dimension Library is distributed in the hope that it will be * + * useful, but WITHOUT ANY WARRANTY; without even the implied warranty * + * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * + * Lesser General Public License for more details. * + * * + * You should have received a copy of the GNU Lesser General Public * + * License along with this program. If not, see * + * . * + *************************************************************************/ + +#include "dimension.h" + +/* + * Checker pattern + */ + +static double +dmnsn_checker_pattern_fn(const dmnsn_pattern *checker, dmnsn_vector v) +{ + double xmod = fmod(v.x, 2.0); + double ymod = fmod(v.y, 2.0); + double zmod = fmod(v.z, 2.0); + + if (xmod < -dmnsn_epsilon) + xmod += 2.0; + if (ymod < -dmnsn_epsilon) + ymod += 2.0; + if (zmod < -dmnsn_epsilon) + zmod += 2.0; + + /* Return 0 when an even number of coordinates are in [0, 1), 1 otherwise */ + unsigned int n = 0; + if (xmod >= 1.0) + ++n; + if (ymod >= 1.0) + ++n; + if (zmod >= 1.0) + ++n; + return (n%2 == 0) ? 0.0 : 1.0; +} + +dmnsn_pattern * +dmnsn_new_checker_pattern() +{ + dmnsn_pattern *checker = dmnsn_new_pattern(); + checker->pattern_fn = &dmnsn_checker_pattern_fn; + return checker; +} -- cgit v1.2.3