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+// Emacs style mode select -*- C++ -*-
+//-----------------------------------------------------------------------------
+//
+// $Id: tables.h 4 2005-07-23 16:19:41Z fraggle $
+//
+// Copyright (C) 1993-1996 by id Software, Inc.
+//
+// This source is available for distribution and/or modification
+// only under the terms of the DOOM Source Code License as
+// published by id Software. All rights reserved.
+//
+// The source is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// FITNESS FOR A PARTICULAR PURPOSE. See the DOOM Source Code License
+// for more details.
+//
+// DESCRIPTION:
+// Lookup tables.
+// Do not try to look them up :-).
+// In the order of appearance:
+//
+// int finetangent[4096] - Tangens LUT.
+// Should work with BAM fairly well (12 of 16bit,
+// effectively, by shifting).
+//
+// int finesine[10240] - Sine lookup.
+// Guess what, serves as cosine, too.
+// Remarkable thing is, how to use BAMs with this?
+//
+// int tantoangle[2049] - ArcTan LUT,
+// maps tan(angle) to angle fast. Gotta search.
+//
+//-----------------------------------------------------------------------------
+
+
+#ifndef __TABLES__
+#define __TABLES__
+
+
+
+#ifdef LINUX
+#include <math.h>
+#else
+#define PI 3.141592657
+#endif
+
+
+#include "m_fixed.h"
+
+#define FINEANGLES 8192
+#define FINEMASK (FINEANGLES-1)
+
+
+// 0x100000000 to 0x2000
+#define ANGLETOFINESHIFT 19
+
+// Effective size is 10240.
+extern fixed_t finesine[5*FINEANGLES/4];
+
+// Re-use data, is just PI/2 pahse shift.
+extern fixed_t* finecosine;
+
+
+// Effective size is 4096.
+extern fixed_t finetangent[FINEANGLES/2];
+
+// Binary Angle Measument, BAM.
+#define ANG45 0x20000000
+#define ANG90 0x40000000
+#define ANG180 0x80000000
+#define ANG270 0xc0000000
+
+
+#define SLOPERANGE 2048
+#define SLOPEBITS 11
+#define DBITS (FRACBITS-SLOPEBITS)
+
+typedef unsigned angle_t;
+
+
+// Effective size is 2049;
+// The +1 size is to handle the case when x==y
+// without additional checking.
+extern angle_t tantoangle[SLOPERANGE+1];
+
+
+// Utility function,
+// called by R_PointToAngle.
+int
+SlopeDiv
+( unsigned num,
+ unsigned den);
+
+
+#endif
+//-----------------------------------------------------------------------------
+//
+// $Log$
+// Revision 1.1 2005/07/23 16:20:27 fraggle
+// Initial revision
+//
+//
+//-----------------------------------------------------------------------------