Line data    Source code

       1           0 : /*
       2             : 
       3             : OOFastArithmetic.h
       4             : 
       5             : Mathematical framework for Oolite.
       6             : 
       7             : Oolite
       8             : Copyright (C) 2004-2013 Giles C Williams and contributors
       9             : 
      10             : This program is free software; you can redistribute it and/or
      11             : modify it under the terms of the GNU General Public License
      12             : as published by the Free Software Foundation; either version 2
      13             : of the License, or (at your option) any later version.
      14             : 
      15             : This program is distributed in the hope that it will be useful,
      16             : but WITHOUT ANY WARRANTY; without even the implied warranty of
      17             : MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
      18             : GNU General Public License for more details.
      19             : 
      20             : You should have received a copy of the GNU General Public License
      21             : along with this program; if not, write to the Free Software
      22             : Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
      23             : MA 02110-1301, USA.
      24             : 
      25             : */
      26             : 
      27             : 
      28             : #ifndef INCLUDED_OOMATHS_h
      29             :         #error Do not include OOFastArithmetic.h directly; include OOMaths.h.
      30             : #else
      31             : 
      32             : 
      33             : /* Clamp to range. */
      34             : OOINLINE float OOClamp_0_1_f(float value) INLINE_CONST_FUNC;
      35             : OOINLINE float OOClamp_n1_1_f(float value) INLINE_CONST_FUNC;
      36             : OOINLINE double OOClamp_0_1_d(double value) INLINE_CONST_FUNC;
      37             : OOINLINE float OOClamp_0_max_f(float value, float max) INLINE_CONST_FUNC;
      38             : OOINLINE double OOClamp_0_max_d(double value, double max) INLINE_CONST_FUNC;
      39             : 
      40             : /* Linear interpolation. */
      41             : OOINLINE float OOLerp(float v0, float v1, float fraction) INLINE_CONST_FUNC;
      42             : OOINLINE double OOLerpd(double v0, double v1, double fraction) INLINE_CONST_FUNC;
      43             : 
      44             : 
      45             : /* Round integer up to nearest power of 2. NOTE: these return 0 if the high bit of value is set. */
      46             : OOINLINE INLINE_CONST_FUNC uint32_t OORoundUpToPowerOf2_32(uint32_t value)
      47             : {
      48             :         return 0x80000000U >> (__builtin_clz(value - 1) - 1);
      49             : }
      50             : 
      51             : 
      52             : OOINLINE INLINE_CONST_FUNC uint64_t OORoundUpToPowerOf2_64(uint64_t value)
      53             : {
      54             :         return 0x8000000000000000ULL >> (__builtin_clzll(value - 1) - 1);
      55             : }
      56             : 
      57             : 
      58             : #if __OBJC__
      59             : #if OOLITE_64_BIT
      60             : OOINLINE INLINE_CONST_FUNC NSUInteger OORoundUpToPowerOf2_NS(NSUInteger value)
      61             : {
      62             :         return OORoundUpToPowerOf2_64(value);
      63             : }
      64             : #else
      65             : OOINLINE INLINE_CONST_FUNC NSUInteger OORoundUpToPowerOf2_NS(NSUInteger value)
      66             : {
      67             :         return OORoundUpToPowerOf2_32(value);
      68             : }
      69             : #endif
      70             : #endif
      71             : 
      72             : 
      73             : OOINLINE float OOClamp_0_1_f(float value)
      74             : {
      75             :         return fmax(0.0f, fmin(value, 1.0f));
      76             : }
      77             : 
      78             : OOINLINE float OOClamp_n1_1_f(float value)
      79             : {
      80             :         return fmax(-1.0f, fmin(value, 1.0f));
      81             : }
      82             : 
      83             : OOINLINE double OOClamp_0_1_d(double value)
      84             : {
      85             :         return fmax(0.0f, fmin(value, 1.0f));
      86             : }
      87             : 
      88             : OOINLINE float OOClamp_0_max_f(float value, float max)
      89             : {
      90             :         return fmax(0.0f, fmin(value, max));
      91             : }
      92             : 
      93             : OOINLINE double OOClamp_0_max_d(double value, double max)
      94             : {
      95             :         return fmax(0.0, fmin(value, max));
      96             : }
      97             : 
      98             : 
      99             : OOINLINE float OOLerp(float v0, float v1, float fraction)
     100             : {
     101             :         // Linear interpolation - equivalent to v0 * (1.0f - fraction) + v1 * fraction.
     102             :         return v0 + fraction * (v1 - v0);
     103             : }
     104             : 
     105             : OOINLINE double OOLerpd(double v0, double v1, double fraction)
     106             : {
     107             :         // Linear interpolation - equivalent to v0 * (1.0 - fraction) + v1 * fraction.
     108             :         return v0 + fraction * (v1 - v0);
     109             : }
     110             : 
     111             : 
     112             : 
     113             : #endif  /* INCLUDED_OOMATHS_h */