+++ /dev/null
-/***************************************************************************/
-/* */
-/* fttrigon.h */
-/* */
-/* FreeType trigonometric functions (specification). */
-/* */
-/* Copyright 2001 by */
-/* David Turner, Robert Wilhelm, and Werner Lemberg. */
-/* */
-/* This file is part of the FreeType project, and may only be used, */
-/* modified, and distributed under the terms of the FreeType project */
-/* license, LICENSE.TXT. By continuing to use, modify, or distribute */
-/* this file you indicate that you have read the license and */
-/* understand and accept it fully. */
-/* */
-/***************************************************************************/
-
-
-#ifndef __FTTRIGON_H__
-#define __FTTRIGON_H__
-
-#include FT_FREETYPE_H
-
-
-FT_BEGIN_HEADER
-
-
- /*************************************************************************/
- /* */
- /* @section: */
- /* computations */
- /* */
- /*************************************************************************/
-
-
- /*************************************************************************/
- /* */
- /* @type: */
- /* FT_Angle */
- /* */
- /* @description: */
- /* This type is used to model angle values in FreeType. Note that */
- /* the angle is a 16.16 fixed float value expressed in degrees. */
- /* */
- typedef FT_Fixed FT_Angle;
-
-
- /*************************************************************************/
- /* */
- /* @macro: */
- /* FT_ANGLE_PI */
- /* */
- /* @description: */
- /* The angle pi expressed in @FT_Angle units. */
- /* */
-#define FT_ANGLE_PI ( 180L << 16 )
-
-
- /*************************************************************************/
- /* */
- /* @macro: */
- /* FT_ANGLE_2PI */
- /* */
- /* @description: */
- /* The angle 2*pi expressed in @FT_Angle units. */
- /* */
-#define FT_ANGLE_2PI ( FT_ANGLE_PI * 2 )
-
-
- /*************************************************************************/
- /* */
- /* @macro: */
- /* FT_ANGLE_PI2 */
- /* */
- /* @description: */
- /* The angle pi/2 expressed in @FT_Angle units. */
- /* */
-#define FT_ANGLE_PI2 ( FT_ANGLE_PI / 2 )
-
-
- /*************************************************************************/
- /* */
- /* @macro: */
- /* FT_ANGLE_PI4 */
- /* */
- /* @description: */
- /* The angle pi/4 expressed in @FT_Angle units. */
- /* */
-#define FT_ANGLE_PI4 ( FT_ANGLE_PI / 4 )
-
-
- /*************************************************************************/
- /* */
- /* @function: */
- /* FT_Sin */
- /* */
- /* @description: */
- /* Return the sinus of a given angle in fixed point format. */
- /* */
- /* @input: */
- /* angle :: The input angle. */
- /* */
- /* @return: */
- /* The sinus value. */
- /* */
- /* @note: */
- /* If you need both the sinus and cosinus for a given angle, use the */
- /* function @FT_Vector_Unit. */
- /* */
- FT_EXPORT( FT_Fixed )
- FT_Sin( FT_Angle angle );
-
-
- /*************************************************************************/
- /* */
- /* @function: */
- /* FT_Cos */
- /* */
- /* @description: */
- /* Return the cosinus of a given angle in fixed point format. */
- /* */
- /* @input: */
- /* angle :: The input angle. */
- /* */
- /* @return: */
- /* The cosinus value. */
- /* */
- /* @note: */
- /* If you need both the sinus and cosinus for a given angle, use the */
- /* function @FT_Vector_Unit. */
- /* */
- FT_EXPORT( FT_Fixed )
- FT_Cos( FT_Angle angle );
-
-
- /*************************************************************************/
- /* */
- /* @function: */
- /* FT_Tan */
- /* */
- /* @description: */
- /* Return the tangent of a given angle in fixed point format. */
- /* */
- /* @input: */
- /* angle :: The input angle. */
- /* */
- /* @return: */
- /* The tangent value. */
- /* */
- FT_EXPORT( FT_Fixed )
- FT_Tan( FT_Angle angle );
-
-
- /*************************************************************************/
- /* */
- /* @function: */
- /* FT_Atan2 */
- /* */
- /* @description: */
- /* Return the arc-tangent corresponding to a given vector (x,y) in */
- /* the 2d plane. */
- /* */
- /* @input: */
- /* x :: The horizontal vector coordinate. */
- /* */
- /* y :: The vertical vector coordinate. */
- /* */
- /* @return: */
- /* The arc-tangent value (i.e. angle). */
- /* */
- FT_EXPORT( FT_Angle )
- FT_Atan2( FT_Fixed x,
- FT_Fixed y );
-
-
- /*************************************************************************/
- /* */
- /* @function: */
- /* FT_Vector_Unit */
- /* */
- /* @description: */
- /* Return the unit vector corresponding to a given angle. After the */
- /* call, the value of `vec.x' will be `sin(angle)', and the value of */
- /* `vec.y' will be `cos(angle)'. */
- /* */
- /* This function is useful to retrieve both the sinus and cosinus of */
- /* a given angle quickly. */
- /* */
- /* @output: */
- /* vec :: The address of target vector. */
- /* */
- /* @input: */
- /* angle :: The address of angle. */
- /* */
- FT_EXPORT( void )
- FT_Vector_Unit( FT_Vector* vec,
- FT_Angle angle );
-
-
- /*************************************************************************/
- /* */
- /* @function: */
- /* FT_Vector_Rotate */
- /* */
- /* @description: */
- /* Rotate a vector by a given angle. */
- /* */
- /* @inout: */
- /* vec :: The address of target vector. */
- /* */
- /* @input: */
- /* angle :: The address of angle. */
- /* */
- FT_EXPORT( void )
- FT_Vector_Rotate( FT_Vector* vec,
- FT_Angle angle );
-
-
- /*************************************************************************/
- /* */
- /* @function: */
- /* FT_Vector_Length */
- /* */
- /* @description: */
- /* Return the length of a given vector. */
- /* */
- /* @input: */
- /* vec :: The address of target vector. */
- /* */
- /* @return: */
- /* The vector length, expressed in the same units that the original */
- /* vector coordinates. */
- /* */
- FT_EXPORT( FT_Fixed )
- FT_Vector_Length( FT_Vector* vec );
-
-
- /*************************************************************************/
- /* */
- /* @function: */
- /* FT_Vector_Normalize */
- /* */
- /* @description: */
- /* Normalize a given vector (i.e. compute the equivalent unit */
- /* vector). */
- /* */
- /* @inout: */
- /* vec :: The address of target vector. */
- /* */
- FT_EXPORT( void )
- FT_Vector_Normalize( FT_Vector* vec );
-
-
- /*************************************************************************/
- /* */
- /* @function: */
- /* FT_Vector_Polarize */
- /* */
- /* @description: */
- /* Compute both the length and angle of a given vector. */
- /* */
- /* @input: */
- /* vec :: The address of source vector. */
- /* */
- /* @output: */
- /* length :: The vector length. */
- /* angle :: The vector angle. */
- /* */
- FT_EXPORT( void )
- FT_Vector_Polarize( FT_Vector* vec,
- FT_Fixed *length,
- FT_Angle *angle );
- /* */
-
-
-FT_END_HEADER
-
-#endif /* __FTTRIGON_H__ */
-
-
-/* END */
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