| // |
| // Copyright (c) 2002-2010 The ANGLE Project Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| // |
| |
| // mathutil.h: Math and bit manipulation functions. |
| |
| #ifndef LIBGLESV2_MATHUTIL_H_ |
| #define LIBGLESV2_MATHUTIL_H_ |
| |
| #include <intrin.h> |
| #include <math.h> |
| #include <windows.h> |
| |
| namespace gl |
| { |
| inline bool isPow2(int x) |
| { |
| return (x & (x - 1)) == 0 && (x != 0); |
| } |
| |
| inline int log2(int x) |
| { |
| int r = 0; |
| while ((x >> r) > 1) r++; |
| return r; |
| } |
| |
| inline unsigned int ceilPow2(unsigned int x) |
| { |
| if (x != 0) x--; |
| x |= x >> 1; |
| x |= x >> 2; |
| x |= x >> 4; |
| x |= x >> 8; |
| x |= x >> 16; |
| x++; |
| |
| return x; |
| } |
| |
| template<typename T, typename MIN, typename MAX> |
| inline T clamp(T x, MIN min, MAX max) |
| { |
| return x < min ? min : (x > max ? max : x); |
| } |
| |
| inline float clamp01(float x) |
| { |
| return clamp(x, 0.0f, 1.0f); |
| } |
| |
| template<const int n> |
| inline unsigned int unorm(float x) |
| { |
| const unsigned int max = 0xFFFFFFFF >> (32 - n); |
| |
| if (x > 1) |
| { |
| return max; |
| } |
| else if (x < 0) |
| { |
| return 0; |
| } |
| else |
| { |
| return (unsigned int)(max * x + 0.5f); |
| } |
| } |
| |
| inline bool supportsSSE2() |
| { |
| static bool checked = false; |
| static bool supports = false; |
| |
| if (checked) |
| { |
| return supports; |
| } |
| |
| int info[4]; |
| __cpuid(info, 0); |
| |
| if (info[0] >= 1) |
| { |
| __cpuid(info, 1); |
| |
| supports = (info[3] >> 26) & 1; |
| } |
| |
| checked = true; |
| |
| return supports; |
| } |
| } |
| |
| #endif // LIBGLESV2_MATHUTIL_H_ |