gbdev/rgbds
1
0
Fork 0
mirror of https://github.com/gbdev/rgbds.git synced 2025-11-20 18:22:07 +00:00
Code Issues Packages Projects Releases Wiki Activity

Use macros to convert between radians and fixed-point 65536ths

Browse Source
This commit is contained in:
Rangi
2021-02-16 18:07:05 -05:00
parent ee20d9010e
commit c67a696a87
1 changed files with 11 additions and 7 deletions
Download Patch File Download Diff File Expand all files Collapse all files

18
src/asm/math.c
View File

@@ -22,6 +22,10 @@
#define fx2double(i) ((double)((i) / 65536.0)) #define fx2double(i) ((double)((i) / 65536.0))
#define double2fx(d) ((int32_t)round((d) * 65536.0)) #define double2fx(d) ((int32_t)round((d) * 65536.0))
// pi radians == 32768 fixed-point "degrees"
#define fdeg2rad(f) ((f) * (M_PI / 32768.0))
#define rad2fdeg(r) ((r) * (32768.0 / M_PI))
#ifndef M_PI #ifndef M_PI
#define M_PI 3.14159265358979323846 #define M_PI 3.14159265358979323846
#endif #endif
@@ -58,7 +62,7 @@ void math_Print(int32_t i)
*/ */
int32_t math_Sin(int32_t i) int32_t math_Sin(int32_t i)
{ {
return double2fx(sin(fx2double(i) * 2 * M_PI / 65536)); return double2fx(sin(fdeg2rad(fx2double(i))));
} }
/* /*
@@ -66,7 +70,7 @@ int32_t math_Sin(int32_t i)
*/ */
int32_t math_Cos(int32_t i) int32_t math_Cos(int32_t i)
{ {
return double2fx(cos(fx2double(i) * 2 * M_PI / 65536)); return double2fx(cos(fdeg2rad(fx2double(i))));
} }
/* /*
@@ -74,7 +78,7 @@ int32_t math_Cos(int32_t i)
*/ */
int32_t math_Tan(int32_t i) int32_t math_Tan(int32_t i)
{ {
return double2fx(tan(fx2double(i) * 2 * M_PI / 65536)); return double2fx(tan(fdeg2rad(fx2double(i))));
} }
/* /*
@@ -82,7 +86,7 @@ int32_t math_Tan(int32_t i)
*/ */
int32_t math_ASin(int32_t i) int32_t math_ASin(int32_t i)
{ {
return double2fx(asin(fx2double(i)) / 2 / M_PI * 65536); return double2fx(rad2fdeg(asin(fx2double(i))));
} }
/* /*
@@ -90,7 +94,7 @@ int32_t math_ASin(int32_t i)
*/ */
int32_t math_ACos(int32_t i) int32_t math_ACos(int32_t i)
{ {
return double2fx(acos(fx2double(i)) / 2 / M_PI * 65536); return double2fx(rad2fdeg(acos(fx2double(i))));
} }
/* /*
@@ -98,7 +102,7 @@ int32_t math_ACos(int32_t i)
*/ */
int32_t math_ATan(int32_t i) int32_t math_ATan(int32_t i)
{ {
return double2fx(atan(fx2double(i)) / 2 / M_PI * 65536); return double2fx(rad2fdeg(atan(fx2double(i))));
} }
/* /*
@@ -106,7 +110,7 @@ int32_t math_ATan(int32_t i)
*/ */
int32_t math_ATan2(int32_t i, int32_t j) int32_t math_ATan2(int32_t i, int32_t j)
{ {
return double2fx(atan2(fx2double(i), fx2double(j)) / 2 / M_PI * 65536); return double2fx(rad2fdeg(atan2(fx2double(i), fx2double(j))));
} }
/* /*