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#ifndef _SHEWCHUK_PREDICATES_H
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#define _SHEWCHUK_PREDICATES_H
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/*****************************************************************************/
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/* Routines for Arbitrary Precision Floating-point Arithmetic */
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/* and Fast Robust Geometric Predicates */
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/* Placed in the public domain by */
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/* Jonathan Richard Shewchuk */
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/* School of Computer Science */
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/* Carnegie Mellon University */
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/* 5000 Forbes Avenue */
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/* Pittsburgh, Pennsylvania 15213-3891 */
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/* This file contains C implementation of algorithms for exact addition */
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/* and multiplication of floating-point numbers, and predicates for */
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/* robustly performing the orientation and incircle tests used in */
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/* computational geometry. The algorithms and underlying theory are */
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/* described in Jonathan Richard Shewchuk. "Adaptive Precision Floating- */
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/* Point Arithmetic and Fast Robust Geometric Predicates." Technical */
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/* Report CMU-CS-96-140, School of Computer Science, Carnegie Mellon */
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/* University, Pittsburgh, Pennsylvania, May 1996. (Submitted to */
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/* Discrete & Computational Geometry.) */
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/* This file, the paper listed above, and other information are available */
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/* from the Web page http://www.cs.cmu.edu/~quake/robust.html . */
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/*****************************************************************************/
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/*****************************************************************************/
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/* Using this code: */
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/* First, read the short or long version of the paper (from the Web page */
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/* Be sure to call exactinit() once, before calling any of the arithmetic */
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/* functions or geometric predicates. Also be sure to turn on the */
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/* optimizer when compiling this file. */
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/* Several geometric predicates are defined. Their parameters are all */
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/* points. Each point is an array of two or three floating-point */
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/* numbers. The geometric predicates, described in the papers, are */
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/* orient2d(pa, pb, pc) */
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/* orient2dfast(pa, pb, pc) */
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/* orient3d(pa, pb, pc, pd) */
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/* orient3dfast(pa, pb, pc, pd) */
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/* incircle(pa, pb, pc, pd) */
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/* incirclefast(pa, pb, pc, pd) */
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/* insphere(pa, pb, pc, pd, pe) */
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/* inspherefast(pa, pb, pc, pd, pe) */
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/* Those with suffix "fast" are approximate, non-robust versions. Those */
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/* without the suffix are adaptive precision, robust versions. There */
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/* are also versions with the suffices "exact" and "slow", which are */
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/* non-adaptive, exact arithmetic versions, which I use only for timings */
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/* in my arithmetic papers. */
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/*****************************************************************************/
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double orient2dfast (double *pa, double *pb, double *pc);
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double orient2dexact(double *pa, double *pb, double *pc);
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double orient2dslow (double *pa, double *pb, double *pc);
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double orient2d (double *pa, double *pb, double *pc);
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double orient3dfast (double *pa, double *pb, double *pc, double *pd);
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double orient3dexact(double *pa, double *pb, double *pc, double *pd);
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double orient3dslow (double *pa, double *pb, double *pc, double *pd);
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double orient3d (double *pa, double *pb, double *pc, double *pd);
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#endif // _SHEWCHUK_PREDICATES_H
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nfem/basis/predicates.h
