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/* $Id: fixed.h,v 1.5 2000/02/12 23:09:22 brianp Exp $ */
/*
* Mesa 3-D graphics library
* Version: 3.1
*
* Copyright (C) 1999 Brian Paul All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included
* in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
* AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
#ifndef FIXED_H
#define FIXED_H
typedef int GLfixed;
#define FIXED_ONE 0x00000800
#define FIXED_HALF 0x00000400
#define FIXED_FRAC_MASK 0x000007FF
#define FIXED_INT_MASK (~FIXED_FRAC_MASK)
#define FIXED_EPSILON 1
#define FIXED_SCALE 2048.0f
#define FIXED_SHIFT 11
#define FloatToFixed(X) ((GLfixed) ((X) * FIXED_SCALE))
#define IntToFixed(I) ((I) << FIXED_SHIFT)
#define FixedToInt(X) ((X) >> FIXED_SHIFT)
#define FixedToUns(X) (((unsigned int)(X)) >> 11)
#define FixedCeil(X) (((X) + FIXED_ONE - FIXED_EPSILON) & FIXED_INT_MASK)
#define FixedFloor(X) ((X) & FIXED_INT_MASK)
/* 0.00048828125 = 1/FIXED_SCALE */
#define FixedToFloat(X) ((X) * 0.00048828125f)
#define PosFloatToFixed(X) FloatToFixed(X)
#define SignedFloatToFixed(X) FloatToFixed(X)
#if DEPTH_BITS==16
/* use fixed-point interpolation */
#define FixedToDepth(I) ((I) >> FIXED_SHIFT)
#else
/* don't really use fixed-point */
#define FixedToDepth(I) (I)
#endif
#endif
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