trig_lut.h

fixed point trig functions. Angle can be in the range of -32768 to 32767. There are 32768 degrees in the unit circle used by nds. To convert between standard degrees (360 per circle): [詳細]

#include <nds/ndstypes.h>

ソースコードを見る。

マクロ定義
#define	DEGREES_IN_CIRCLE   (1 << 15)
#define	fixedToInt(n, bits)   ((int)((n)>>(bits)))
#define	intToFixed(n, bits)   ((int)((n)<<(bits)))
#define	floatToFixed(n, bits)   ((int)((n) * (float)(1<<(bits))))
#define	fixedToFloat(n, bits)   (((float)(n)) / (float)(1<<(bits)))
#define	floorFixed(n, bits)   ((int)((n) & ~(((1 << (bits)) - 1))))
#define	degreesToAngle(degrees)   ((degrees) * DEGREES_IN_CIRCLE / 360)
#define	angleToDegrees(angle)   ((angle) * 360 / DEGREES_IN_CIRCLE)
関数
s16	cosLerp (s16 angle)
	fixed point cosine
s16	sinLerp (s16 angle)
	fixed point sine
s32	tanLerp (s16 angle)
	fixed point tangent
s16	acosLerp (s16 par)
	fixed point arccos
s16	asinLerp (s16 par)
	fixed point arcsin

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説明

fixed point trig functions. Angle can be in the range of -32768 to 32767. There are 32768 degrees in the unit circle used by nds. To convert between standard degrees (360 per circle):

angle = degreesToAngle(angleInDegrees);

or

angle = angleInDegrees * 32768 / 360;

This unit of measure is sometimes refered to as a binary radian (brad) or binary degree. It allows for more precise representation of angle and faster calculation as the DS has no floating point processor.

---

関数

s16 acosLerp

(

s16

par

)

fixed point arccos

引数:

par

parameter

戻り値:

s16 angle (-32768 to 32767)

s16 asinLerp

(

s16

par

)

fixed point arcsin

引数:

par

parameter

戻り値:

s16 angle (-32768 to 32767)

s16 cosLerp

(

s16

angle

)

fixed point cosine

引数:

angle

(-32768 to 32767)

戻り値:

4.12 fixed point number with the range [-1, 1]

例:

Graphics/3D/nehe/lesson10/source/nehe10.cpp, Graphics/3D/nehe/lesson10b/source/nehe10b.cpp, Graphics/3D/nehe/lesson11/source/nehe11.cpp, と input/Touch_Pad/touch_look/source/main.cpp.

s16 sinLerp

(

s16

angle

)

fixed point sine

引数:

angle

(-32768 to 32767)

戻り値:

4.12 fixed point number with the range [-1, 1]

例:

Graphics/3D/nehe/lesson10/source/nehe10.cpp, Graphics/3D/nehe/lesson10b/source/nehe10b.cpp, Graphics/3D/nehe/lesson11/source/nehe11.cpp, と input/Touch_Pad/touch_look/source/main.cpp.

s32 tanLerp

(

s16

angle

)

fixed point tangent

引数:

angle

(-32768 to 32767)

戻り値:

20.12 fixed point number with the range [-81.483, 524287.999]