michael@0: /***************************************************************************/
michael@0: /*                                                                         */
michael@0: /*  fttrigon.h                                                             */
michael@0: /*                                                                         */
michael@0: /*    FreeType trigonometric functions (specification).                    */
michael@0: /*                                                                         */
michael@0: /*  Copyright 2001, 2003, 2005, 2007, 2013 by                              */
michael@0: /*  David Turner, Robert Wilhelm, and Werner Lemberg.                      */
michael@0: /*                                                                         */
michael@0: /*  This file is part of the FreeType project, and may only be used,       */
michael@0: /*  modified, and distributed under the terms of the FreeType project      */
michael@0: /*  license, LICENSE.TXT.  By continuing to use, modify, or distribute     */
michael@0: /*  this file you indicate that you have read the license and              */
michael@0: /*  understand and accept it fully.                                        */
michael@0: /*                                                                         */
michael@0: /***************************************************************************/
michael@0: 
michael@0: 
michael@0: #ifndef __FTTRIGON_H__
michael@0: #define __FTTRIGON_H__
michael@0: 
michael@0: #include FT_FREETYPE_H
michael@0: 
michael@0: #ifdef FREETYPE_H
michael@0: #error "freetype.h of FreeType 1 has been loaded!"
michael@0: #error "Please fix the directory search order for header files"
michael@0: #error "so that freetype.h of FreeType 2 is found first."
michael@0: #endif
michael@0: 
michael@0: 
michael@0: FT_BEGIN_HEADER
michael@0: 
michael@0: 
michael@0:   /*************************************************************************/
michael@0:   /*                                                                       */
michael@0:   /* <Section>                                                             */
michael@0:   /*   computations                                                        */
michael@0:   /*                                                                       */
michael@0:   /*************************************************************************/
michael@0: 
michael@0: 
michael@0:   /*************************************************************************
michael@0:    *
michael@0:    * @type:
michael@0:    *   FT_Angle
michael@0:    *
michael@0:    * @description:
michael@0:    *   This type is used to model angle values in FreeType.  Note that the
michael@0:    *   angle is a 16.16 fixed-point value expressed in degrees.
michael@0:    *
michael@0:    */
michael@0:   typedef FT_Fixed  FT_Angle;
michael@0: 
michael@0: 
michael@0:   /*************************************************************************
michael@0:    *
michael@0:    * @macro:
michael@0:    *   FT_ANGLE_PI
michael@0:    *
michael@0:    * @description:
michael@0:    *   The angle pi expressed in @FT_Angle units.
michael@0:    *
michael@0:    */
michael@0: #define FT_ANGLE_PI  ( 180L << 16 )
michael@0: 
michael@0: 
michael@0:   /*************************************************************************
michael@0:    *
michael@0:    * @macro:
michael@0:    *   FT_ANGLE_2PI
michael@0:    *
michael@0:    * @description:
michael@0:    *   The angle 2*pi expressed in @FT_Angle units.
michael@0:    *
michael@0:    */
michael@0: #define FT_ANGLE_2PI  ( FT_ANGLE_PI * 2 )
michael@0: 
michael@0: 
michael@0:   /*************************************************************************
michael@0:    *
michael@0:    * @macro:
michael@0:    *   FT_ANGLE_PI2
michael@0:    *
michael@0:    * @description:
michael@0:    *   The angle pi/2 expressed in @FT_Angle units.
michael@0:    *
michael@0:    */
michael@0: #define FT_ANGLE_PI2  ( FT_ANGLE_PI / 2 )
michael@0: 
michael@0: 
michael@0:   /*************************************************************************
michael@0:    *
michael@0:    * @macro:
michael@0:    *   FT_ANGLE_PI4
michael@0:    *
michael@0:    * @description:
michael@0:    *   The angle pi/4 expressed in @FT_Angle units.
michael@0:    *
michael@0:    */
michael@0: #define FT_ANGLE_PI4  ( FT_ANGLE_PI / 4 )
michael@0: 
michael@0: 
michael@0:   /*************************************************************************
michael@0:    *
michael@0:    * @function:
michael@0:    *   FT_Sin
michael@0:    *
michael@0:    * @description:
michael@0:    *   Return the sinus of a given angle in fixed-point format.
michael@0:    *
michael@0:    * @input:
michael@0:    *   angle ::
michael@0:    *     The input angle.
michael@0:    *
michael@0:    * @return:
michael@0:    *   The sinus value.
michael@0:    *
michael@0:    * @note:
michael@0:    *   If you need both the sinus and cosinus for a given angle, use the
michael@0:    *   function @FT_Vector_Unit.
michael@0:    *
michael@0:    */
michael@0:   FT_EXPORT( FT_Fixed )
michael@0:   FT_Sin( FT_Angle  angle );
michael@0: 
michael@0: 
michael@0:   /*************************************************************************
michael@0:    *
michael@0:    * @function:
michael@0:    *   FT_Cos
michael@0:    *
michael@0:    * @description:
michael@0:    *   Return the cosinus of a given angle in fixed-point format.
michael@0:    *
michael@0:    * @input:
michael@0:    *   angle ::
michael@0:    *     The input angle.
michael@0:    *
michael@0:    * @return:
michael@0:    *   The cosinus value.
michael@0:    *
michael@0:    * @note:
michael@0:    *   If you need both the sinus and cosinus for a given angle, use the
michael@0:    *   function @FT_Vector_Unit.
michael@0:    *
michael@0:    */
michael@0:   FT_EXPORT( FT_Fixed )
michael@0:   FT_Cos( FT_Angle  angle );
michael@0: 
michael@0: 
michael@0:   /*************************************************************************
michael@0:    *
michael@0:    * @function:
michael@0:    *   FT_Tan
michael@0:    *
michael@0:    * @description:
michael@0:    *   Return the tangent of a given angle in fixed-point format.
michael@0:    *
michael@0:    * @input:
michael@0:    *   angle ::
michael@0:    *     The input angle.
michael@0:    *
michael@0:    * @return:
michael@0:    *   The tangent value.
michael@0:    *
michael@0:    */
michael@0:   FT_EXPORT( FT_Fixed )
michael@0:   FT_Tan( FT_Angle  angle );
michael@0: 
michael@0: 
michael@0:   /*************************************************************************
michael@0:    *
michael@0:    * @function:
michael@0:    *   FT_Atan2
michael@0:    *
michael@0:    * @description:
michael@0:    *   Return the arc-tangent corresponding to a given vector (x,y) in
michael@0:    *   the 2d plane.
michael@0:    *
michael@0:    * @input:
michael@0:    *   x ::
michael@0:    *     The horizontal vector coordinate.
michael@0:    *
michael@0:    *   y ::
michael@0:    *     The vertical vector coordinate.
michael@0:    *
michael@0:    * @return:
michael@0:    *   The arc-tangent value (i.e. angle).
michael@0:    *
michael@0:    */
michael@0:   FT_EXPORT( FT_Angle )
michael@0:   FT_Atan2( FT_Fixed  x,
michael@0:             FT_Fixed  y );
michael@0: 
michael@0: 
michael@0:   /*************************************************************************
michael@0:    *
michael@0:    * @function:
michael@0:    *   FT_Angle_Diff
michael@0:    *
michael@0:    * @description:
michael@0:    *   Return the difference between two angles.  The result is always
michael@0:    *   constrained to the ]-PI..PI] interval.
michael@0:    *
michael@0:    * @input:
michael@0:    *   angle1 ::
michael@0:    *     First angle.
michael@0:    *
michael@0:    *   angle2 ::
michael@0:    *     Second angle.
michael@0:    *
michael@0:    * @return:
michael@0:    *   Constrained value of `value2-value1'.
michael@0:    *
michael@0:    */
michael@0:   FT_EXPORT( FT_Angle )
michael@0:   FT_Angle_Diff( FT_Angle  angle1,
michael@0:                  FT_Angle  angle2 );
michael@0: 
michael@0: 
michael@0:   /*************************************************************************
michael@0:    *
michael@0:    * @function:
michael@0:    *   FT_Vector_Unit
michael@0:    *
michael@0:    * @description:
michael@0:    *   Return the unit vector corresponding to a given angle.  After the
michael@0:    *   call, the value of `vec.x' will be `sin(angle)', and the value of
michael@0:    *   `vec.y' will be `cos(angle)'.
michael@0:    *
michael@0:    *   This function is useful to retrieve both the sinus and cosinus of a
michael@0:    *   given angle quickly.
michael@0:    *
michael@0:    * @output:
michael@0:    *   vec ::
michael@0:    *     The address of target vector.
michael@0:    *
michael@0:    * @input:
michael@0:    *   angle ::
michael@0:    *     The address of angle.
michael@0:    *
michael@0:    */
michael@0:   FT_EXPORT( void )
michael@0:   FT_Vector_Unit( FT_Vector*  vec,
michael@0:                   FT_Angle    angle );
michael@0: 
michael@0: 
michael@0:   /*************************************************************************
michael@0:    *
michael@0:    * @function:
michael@0:    *   FT_Vector_Rotate
michael@0:    *
michael@0:    * @description:
michael@0:    *   Rotate a vector by a given angle.
michael@0:    *
michael@0:    * @inout:
michael@0:    *   vec ::
michael@0:    *     The address of target vector.
michael@0:    *
michael@0:    * @input:
michael@0:    *   angle ::
michael@0:    *     The address of angle.
michael@0:    *
michael@0:    */
michael@0:   FT_EXPORT( void )
michael@0:   FT_Vector_Rotate( FT_Vector*  vec,
michael@0:                     FT_Angle    angle );
michael@0: 
michael@0: 
michael@0:   /*************************************************************************
michael@0:    *
michael@0:    * @function:
michael@0:    *   FT_Vector_Length
michael@0:    *
michael@0:    * @description:
michael@0:    *   Return the length of a given vector.
michael@0:    *
michael@0:    * @input:
michael@0:    *   vec ::
michael@0:    *     The address of target vector.
michael@0:    *
michael@0:    * @return:
michael@0:    *   The vector length, expressed in the same units that the original
michael@0:    *   vector coordinates.
michael@0:    *
michael@0:    */
michael@0:   FT_EXPORT( FT_Fixed )
michael@0:   FT_Vector_Length( FT_Vector*  vec );
michael@0: 
michael@0: 
michael@0:   /*************************************************************************
michael@0:    *
michael@0:    * @function:
michael@0:    *   FT_Vector_Polarize
michael@0:    *
michael@0:    * @description:
michael@0:    *   Compute both the length and angle of a given vector.
michael@0:    *
michael@0:    * @input:
michael@0:    *   vec ::
michael@0:    *     The address of source vector.
michael@0:    *
michael@0:    * @output:
michael@0:    *   length ::
michael@0:    *     The vector length.
michael@0:    *
michael@0:    *   angle ::
michael@0:    *     The vector angle.
michael@0:    *
michael@0:    */
michael@0:   FT_EXPORT( void )
michael@0:   FT_Vector_Polarize( FT_Vector*  vec,
michael@0:                       FT_Fixed   *length,
michael@0:                       FT_Angle   *angle );
michael@0: 
michael@0: 
michael@0:   /*************************************************************************
michael@0:    *
michael@0:    * @function:
michael@0:    *   FT_Vector_From_Polar
michael@0:    *
michael@0:    * @description:
michael@0:    *   Compute vector coordinates from a length and angle.
michael@0:    *
michael@0:    * @output:
michael@0:    *   vec ::
michael@0:    *     The address of source vector.
michael@0:    *
michael@0:    * @input:
michael@0:    *   length ::
michael@0:    *     The vector length.
michael@0:    *
michael@0:    *   angle ::
michael@0:    *     The vector angle.
michael@0:    *
michael@0:    */
michael@0:   FT_EXPORT( void )
michael@0:   FT_Vector_From_Polar( FT_Vector*  vec,
michael@0:                         FT_Fixed    length,
michael@0:                         FT_Angle    angle );
michael@0: 
michael@0:   /* */
michael@0: 
michael@0: 
michael@0: FT_END_HEADER
michael@0: 
michael@0: #endif /* __FTTRIGON_H__ */
michael@0: 
michael@0: 
michael@0: /* END */