gba-trycatch
annotate src/sincos.h @ 11:c47e54796b82
added a simple README
| author | John Tsiombikas <nuclear@member.fsf.org> |
|---|---|
| date | Sun, 22 Jun 2014 07:54:29 +0300 |
| parents | 8e9225853d75 |
| children |
| rev | line source |
|---|---|
| nuclear@3 | 1 #ifndef SINCOS_H_ |
| nuclear@3 | 2 #define SINCOS_H_ |
| nuclear@3 | 3 |
| nuclear@3 | 4 #include <stdint.h> |
| nuclear@3 | 5 |
| nuclear@4 | 6 /*#define M_PI_X16 (int32_t)(M_PI * 65536.0) */ |
| nuclear@4 | 7 #define M_PI_X16 (int32_t)((31416 << 16) / 10000) |
| nuclear@3 | 8 |
| nuclear@3 | 9 #define SINLUT_SCALE 512 |
| nuclear@3 | 10 #define SINLUT_SIZE 512 |
| nuclear@3 | 11 int16_t sinlut[SINLUT_SIZE]; |
| nuclear@3 | 12 |
| nuclear@3 | 13 void sincos_init(void); |
| nuclear@3 | 14 |
| nuclear@3 | 15 /* takes angle in [0, SINLUT_SIZE] and returns: |
| nuclear@3 | 16 * sin(2 * angle / SINLUT_SIZE / pi) * SINLUT_SCALE |
| nuclear@3 | 17 */ |
| nuclear@3 | 18 int16_t sin_int(int16_t norm_angle); |
| nuclear@3 | 19 int16_t cos_int(int16_t norm_angle); |
| nuclear@3 | 20 |
| nuclear@3 | 21 /* takes angle in fixed point 16.16 radians [0, 2pi << 16] |
| nuclear@3 | 22 * and returns 16.16 fixed point in [-1 << 16, 1 << 16] |
| nuclear@3 | 23 */ |
| nuclear@3 | 24 int32_t sin_x16(int32_t radians); |
| nuclear@3 | 25 int32_t cos_x16(int32_t radians); |
| nuclear@3 | 26 |
| nuclear@3 | 27 #endif /* SINCOS_H_ */ |