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| #ifndef _FIXP_ARITH_H
| #define _FIXP_ARITH_H
|
| /*
| * Simplistic fixed-point arithmetics.
| * Hmm, I'm probably duplicating some code :(
| *
| * Copyright (c) 2002 Johann Deneux
| */
|
| /*
| * This program is free software; you can redistribute it and/or modify
| * it under the terms of the GNU General Public License as published by
| * the Free Software Foundation; either version 2 of the License, or
| * (at your option) any later version.
| *
| */
|
| #include <linux/types.h>
|
| static const s32 sin_table[] = {
| 0x00000000, 0x023be165, 0x04779632, 0x06b2f1d2, 0x08edc7b6, 0x0b27eb5c,
| 0x0d61304d, 0x0f996a26, 0x11d06c96, 0x14060b67, 0x163a1a7d, 0x186c6ddd,
| 0x1a9cd9ac, 0x1ccb3236, 0x1ef74bf2, 0x2120fb82, 0x234815ba, 0x256c6f9e,
| 0x278dde6e, 0x29ac379f, 0x2bc750e8, 0x2ddf003f, 0x2ff31bdd, 0x32037a44,
| 0x340ff241, 0x36185aee, 0x381c8bb5, 0x3a1c5c56, 0x3c17a4e7, 0x3e0e3ddb,
| 0x3fffffff, 0x41ecc483, 0x43d464fa, 0x45b6bb5d, 0x4793a20f, 0x496af3e1,
| 0x4b3c8c11, 0x4d084650, 0x4ecdfec6, 0x508d9210, 0x5246dd48, 0x53f9be04,
| 0x55a6125a, 0x574bb8e5, 0x58ea90c2, 0x5a827999, 0x5c135399, 0x5d9cff82,
| 0x5f1f5ea0, 0x609a52d1, 0x620dbe8a, 0x637984d3, 0x64dd894f, 0x6639b039,
| 0x678dde6d, 0x68d9f963, 0x6a1de735, 0x6b598ea1, 0x6c8cd70a, 0x6db7a879,
| 0x6ed9eba0, 0x6ff389de, 0x71046d3c, 0x720c8074, 0x730baeec, 0x7401e4bf,
| 0x74ef0ebb, 0x75d31a5f, 0x76adf5e5, 0x777f903b, 0x7847d908, 0x7906c0af,
| 0x79bc384c, 0x7a6831b8, 0x7b0a9f8c, 0x7ba3751c, 0x7c32a67c, 0x7cb82884,
| 0x7d33f0c8, 0x7da5f5a3, 0x7e0e2e31, 0x7e6c924f, 0x7ec11aa3, 0x7f0bc095,
| 0x7f4c7e52, 0x7f834ecf, 0x7fb02dc4, 0x7fd317b3, 0x7fec09e1, 0x7ffb025e,
| 0x7fffffff
| };
|
| /**
| * __fixp_sin32() returns the sin of an angle in degrees
| *
| * @degrees: angle, in degrees, from 0 to 360.
| *
| * The returned value ranges from -0x7fffffff to +0x7fffffff.
| */
| static inline s32 __fixp_sin32(int degrees)
| {
| s32 ret;
| bool negative = false;
|
| if (degrees > 180) {
| negative = true;
| degrees -= 180;
| }
| if (degrees > 90)
| degrees = 180 - degrees;
|
| ret = sin_table[degrees];
|
| return negative ? -ret : ret;
| }
|
| /**
| * fixp_sin32() returns the sin of an angle in degrees
| *
| * @degrees: angle, in degrees. The angle can be positive or negative
| *
| * The returned value ranges from -0x7fffffff to +0x7fffffff.
| */
| static inline s32 fixp_sin32(int degrees)
| {
| degrees = (degrees % 360 + 360) % 360;
|
| return __fixp_sin32(degrees);
| }
|
| /* cos(x) = sin(x + 90 degrees) */
| #define fixp_cos32(v) fixp_sin32((v) + 90)
|
| /*
| * 16 bits variants
| *
| * The returned value ranges from -0x7fff to 0x7fff
| */
|
| #define fixp_sin16(v) (fixp_sin32(v) >> 16)
| #define fixp_cos16(v) (fixp_cos32(v) >> 16)
|
| #endif
|
|
