nuclear@3: #include <math.h>
nuclear@3: #include "sincos.h"
nuclear@3: #include "logger.h"
nuclear@3: 
nuclear@3: void sincos_init(void)
nuclear@3: {
nuclear@3: 	int i;
nuclear@3: 
nuclear@3: 	logmsg(LOG_ALL, "calculating sin/cos lut...\n");
nuclear@3: 
nuclear@3: 	for(i=0; i<SINLUT_SIZE; i++) {
nuclear@3: 		float angle = 2.0 * M_PI * ((float)i / (float)SINLUT_SIZE);
nuclear@3: 		float val = sin(angle);
nuclear@3: 		sinlut[i] = (int16_t)(val * SINLUT_SCALE);
nuclear@3: 	}
nuclear@3: }
nuclear@3: 
nuclear@3: int16_t sin_int(int16_t norm_angle)
nuclear@3: {
nuclear@3: 	norm_angle %= SINLUT_SIZE;
nuclear@3: 	if(norm_angle < 0) {
nuclear@3: 		norm_angle += SINLUT_SIZE;
nuclear@3: 	}
nuclear@3: 	return sinlut[norm_angle];
nuclear@3: }
nuclear@3: 
nuclear@3: int16_t cos_int(int16_t norm_angle)
nuclear@3: {
nuclear@3: 	return sin_int(norm_angle + SINLUT_SIZE / 4);
nuclear@3: }
nuclear@3: 
nuclear@3: int32_t sin_x16(int32_t radians)
nuclear@3: {
nuclear@3: 	int32_t na = (radians << 16) / (M_PI_X16 * 2);
nuclear@3: 	return sin_int((na >> 8) * (SINLUT_SIZE << 8));
nuclear@3: }
nuclear@3: 
nuclear@3: int32_t cos_x16(int32_t radians)
nuclear@3: {
nuclear@3: 	int32_t na = (radians << 16) / (M_PI_X16 * 2);
nuclear@3: 	return cos_int((na >> 8) * (SINLUT_SIZE << 8));
nuclear@3: }