update for HEAD-2003050101

[reactos.git] / lib / freetype / src / autohint / ahangles.c

diff --git a/lib/freetype/src/autohint/ahangles.c b/lib/freetype/src/autohint/ahangles.c
new file mode 100644 (file)
index 0000000..ef5a88e
--- /dev/null
+++ b/lib/freetype/src/autohint/ahangles.c
@@ -0,0 +1,147 @@
+/***************************************************************************/
+/*                                                                         */
+/*  ahangles.h                                                             */
+/*                                                                         */
+/*    A routine used to compute vector angles with limited accuracy        */
+/*    and very high speed (body).                                          */
+/*                                                                         */
+/*  Copyright 2000-2001, 2002 Catharon Productions Inc.                    */
+/*  Author: David Turner                                                   */
+/*                                                                         */
+/*  This file is part of the Catharon Typography Project and shall only    */
+/*  be used, modified, and distributed under the terms of the Catharon     */
+/*  Open Source License that should come with this file under the name     */
+/*  `CatharonLicense.txt'.  By continuing to use, modify, or distribute    */
+/*  this file you indicate that you have read the license and              */
+/*  understand and accept it fully.                                        */
+/*                                                                         */
+/*  Note that this license is compatible with the FreeType license.        */
+/*                                                                         */
+/***************************************************************************/
+
+
+#include <ft2build.h>
+#include "ahangles.h"
+
+
+  /* the following table has been automatically generated with */
+  /* the `mather.py' Python script                             */
+
+  const AH_Angle  ah_arctan[1L << AH_ATAN_BITS] =
+  {
+     0,  0,  1,  1,  1,  2,  2,  2,
+     3,  3,  3,  3,  4,  4,  4,  5,
+     5,  5,  6,  6,  6,  7,  7,  7,
+     8,  8,  8,  9,  9,  9, 10, 10,
+    10, 10, 11, 11, 11, 12, 12, 12,
+    13, 13, 13, 14, 14, 14, 14, 15,
+    15, 15, 16, 16, 16, 17, 17, 17,
+    18, 18, 18, 18, 19, 19, 19, 20,
+    20, 20, 21, 21, 21, 21, 22, 22,
+    22, 23, 23, 23, 24, 24, 24, 24,
+    25, 25, 25, 26, 26, 26, 26, 27,
+    27, 27, 28, 28, 28, 28, 29, 29,
+    29, 30, 30, 30, 30, 31, 31, 31,
+    31, 32, 32, 32, 33, 33, 33, 33,
+    34, 34, 34, 34, 35, 35, 35, 35,
+    36, 36, 36, 36, 37, 37, 37, 38,
+    38, 38, 38, 39, 39, 39, 39, 40,
+    40, 40, 40, 41, 41, 41, 41, 42,
+    42, 42, 42, 42, 43, 43, 43, 43,
+    44, 44, 44, 44, 45, 45, 45, 45,
+    46, 46, 46, 46, 46, 47, 47, 47,
+    47, 48, 48, 48, 48, 48, 49, 49,
+    49, 49, 50, 50, 50, 50, 50, 51,
+    51, 51, 51, 51, 52, 52, 52, 52,
+    52, 53, 53, 53, 53, 53, 54, 54,
+    54, 54, 54, 55, 55, 55, 55, 55,
+    56, 56, 56, 56, 56, 57, 57, 57,
+    57, 57, 57, 58, 58, 58, 58, 58,
+    59, 59, 59, 59, 59, 59, 60, 60,
+    60, 60, 60, 61, 61, 61, 61, 61,
+    61, 62, 62, 62, 62, 62, 62, 63,
+    63, 63, 63, 63, 63, 64, 64, 64
+  };
+
+
+  FT_LOCAL_DEF( AH_Angle )
+  ah_angle( FT_Vector*  v )
+  {
+    FT_Pos    dx, dy;
+    AH_Angle  angle;
+
+
+    dx = v->x;
+    dy = v->y;
+
+    /* check trivial cases */
+    if ( dy == 0 )
+    {
+      angle = 0;
+      if ( dx < 0 )
+        angle = AH_PI;
+      return angle;
+    }
+    else if ( dx == 0 )
+    {
+      angle = AH_HALF_PI;
+      if ( dy < 0 )
+        angle = -AH_HALF_PI;
+      return angle;
+    }
+
+    angle = 0;
+    if ( dx < 0 )
+    {
+      dx = -v->x;
+      dy = -v->y;
+      angle = AH_PI;
+    }
+
+    if ( dy < 0 )
+    {
+      FT_Pos  tmp;
+
+
+      tmp = dx;
+      dx  = -dy;
+      dy  = tmp;
+      angle -= AH_HALF_PI;
+    }
+
+    if ( dx == 0 && dy == 0 )
+      return 0;
+
+    if ( dx == dy )
+      angle += AH_PI / 4;
+    else if ( dx > dy )
+      angle += ah_arctan[FT_DivFix( dy, dx ) >> ( 16 - AH_ATAN_BITS )];
+    else
+      angle += AH_HALF_PI -
+               ah_arctan[FT_DivFix( dx, dy ) >> ( 16 - AH_ATAN_BITS )];
+
+    if ( angle > AH_PI )
+      angle -= AH_2PI;
+
+    return angle;
+  }
+
+
+  FT_LOCAL_DEF( AH_Angle )
+  ah_angle_diff( AH_Angle  angle1,
+                 AH_Angle  angle2 )
+  {
+    AH_Angle  delta;
+    
+
+    delta = ( angle2 - angle1 );
+    if ( delta < 0 )
+      delta += AH_2PI;
+    
+    if ( delta > AH_PI )
+      delta -= AH_2PI;
+    
+    return delta;
+  }                 
+
+/* END */