misc/libfreetype/include/freetype/fttrigon.h
author nemo
Thu, 04 Apr 2013 08:10:59 -0400
changeset 8848 e9ebd63f8a03
parent 5172 88f2e05288ba
permissions -rw-r--r--
So. Some themes have objects that seem to be large natural extensions of the landscape. Masks allow maintaining that. Lemme know if it doesn't look good. If it doesn't, can still use for ice/bounce/indestructible. Indestructible bunker object for example.

/***************************************************************************/
/*                                                                         */
/*  fttrigon.h                                                             */
/*                                                                         */
/*    FreeType trigonometric functions (specification).                    */
/*                                                                         */
/*  Copyright 2001, 2003, 2005, 2007 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

#ifdef FREETYPE_H
#error "freetype.h of FreeType 1 has been loaded!"
#error "Please fix the directory search order for header files"
#error "so that freetype.h of FreeType 2 is found first."
#endif


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_Angle_Diff
   *
   * @description:
   *   Return the difference between two angles.  The result is always
   *   constrained to the ]-PI..PI] interval.
   *
   * @input:
   *   angle1 ::
   *     First angle.
   *
   *   angle2 ::
   *     Second angle.
   *
   * @return:
   *   Constrained value of `value2-value1'.
   *
   */
  FT_EXPORT( FT_Angle )
  FT_Angle_Diff( FT_Angle  angle1,
                 FT_Angle  angle2 );


  /*************************************************************************
   *
   * @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_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 );


  /*************************************************************************
   *
   * @function:
   *   FT_Vector_From_Polar
   *
   * @description:
   *   Compute vector coordinates from a length and angle.
   *
   * @output:
   *   vec ::
   *     The address of source vector.
   *
   * @input:
   *   length ::
   *     The vector length.
   *
   *   angle ::
   *     The vector angle.
   *
   */
  FT_EXPORT( void )
  FT_Vector_From_Polar( FT_Vector*  vec,
                        FT_Fixed    length,
                        FT_Angle    angle );

  /* */


FT_END_HEADER

#endif /* __FTTRIGON_H__ */


/* END */