FixedMath.h

00001 #include "DataTypes.h"
00002 
00003 #ifndef FIXEDMATH_H_
00004 #define FIXEDMATH_H_
00005 
00006 
00007 typedef SIGNED_WORD FIXED_7_8;
00008 typedef SIGNED_WORD FIXED_9_6;
00009 
00010 typedef SIGNED_WORD FIXED_0_15;
00011 typedef SIGNED_WORD FIXED_1_14;
00012 
00013 
00014 extern const FIXED_1_14 Fixed_1_14_SineTable [256];
00015 extern const FIXED_7_8 Fixed_7_8_SineTable [256];
00016 
00017 #define FMul_15_0(A,B)             (FIXED_0_15)(((FIXED_0_15)(A) * (FIXED_0_15 )(B))>>15)
00018 #define FMul_7_8to0_15(A,B)        (FIXED_7_8)(((FIXED_7_8)(A) * (FIXED_0_15)(B))>>15)
00019 #define FMul_15_0to7_8(A,B)        (SIGNED_WORD)(((SIGNED_WORD)(A) * (FIXED_7_8)(B))>>8)
00020 
00021 
00022 
00023 #define INT_7_8(A)                (SIGNED_WORD)(A>>8)
00024 #define INT_TO_7_8(A)            ((FIXED_7_8)(A)<<8)
00025 #define FRAC_7_8(A)                (FIXED_7_8)(A&0xFF)
00026 
00027 #define INT_9_6(A)                (SIGNED_WORD)(A>>6)
00028 #define INT_TO_9_6(A)            ((FIXED_9_6)(A)<<6)
00029 #define FRAC_6_9(A)                (FIXED_9_6)(A&0x3F)
00030 
00031 
00032 
00033 //#define FMul_15_0to0_15            (SIGNED_WORD)(((SIGNED_WORD)(A) * (FIXED_0_15)(B))>>16)
00034 inline SIGNED_WORD FMul_15_0to0_15(SIGNED_WORD A,SIGNED_WORD B)
00035 {
00036     return  (((long)(A) * (long)(B))>>15);
00037 }
00038 
00039 inline SIGNED_WORD FMul_15_0to1_14(SIGNED_WORD A,SIGNED_WORD B)
00040 {
00041     long temp;
00042     temp = (((long)(A) * (long)(B))>>13);
00043     if(temp&0x01)
00044     {
00045         temp = temp>>1;
00046         temp = temp +1;
00047     }
00048     else
00049     {
00050         temp = temp>>1;
00051     }
00052     return  temp;
00053 }
00054 
00055 //inline SIGNED_WORD ABS(A)
00056 //{
00057     //if(A<0)
00058         //return -A;
00059     //else
00060         //return A;    
00061 //}
00062 
00063 #endif /*FIXEDMATH_H_*/