0ad/source/lib/bits.cpp
wraitii 369c2e8801 Further header & precompiled cleanup, fix no-PCH builds.
GUIObjectBase is made a IGUIObject* to avoid including those headers
un-necessarily. Subsequent diffs ought to clean up the various of
pointers for that with a similar type with reference semantics.

Also:
- Add standard C and C++ headers (mostly cstring for memcpy, string and
vector) where needed.
- Swap out some includes for forward declarations
- Clean up un-necessary boost includes in precompiled and other headers.
- Clean up precompiled headers, including fewer things.
- Move ACPI to the windows-specific folder as it's included there only
and mostly specific to that platform.

Thanks Stan for the testing.

Differential Revision: https://code.wildfiregames.com/D3129
This was SVN commit r24352.
2020-12-09 14:39:14 +00:00

45 lines
1.4 KiB
C++

/* Copyright (C) 2020 Wildfire Games.
*
* 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 THE AUTHORS OR COPYRIGHT HOLDERS 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.
*/
/*
* bit-twiddling.
*/
#include "precompiled.h"
#include "lib/bits.h"
#include <cstring>
static inline u32 get_float_bits(const float x)
{
u32 ret;
memcpy(&ret, &x, 4);
return ret;
}
int floor_log2(const float x)
{
const u32 i = get_float_bits(x);
const u32 biased_exp = (i >> 23) & 0xFF;
return (int)biased_exp - 127;
}