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diff --git a/src/3rdparty/freetype/src/sdf/ftsdfcommon.c b/src/3rdparty/freetype/src/sdf/ftsdfcommon.c
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+++ b/src/3rdparty/freetype/src/sdf/ftsdfcommon.c
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+/****************************************************************************
+ *
+ * ftsdfcommon.c
+ *
+ *   Auxiliary data for Signed Distance Field support (body).
+ *
+ * Copyright (C) 2020-2023 by
+ * David Turner, Robert Wilhelm, and Werner Lemberg.
+ *
+ * Written by Anuj Verma.
+ *
+ * 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.
+ *
+ */
+
+
+#include "ftsdf.h"
+#include "ftsdfcommon.h"
+
+
+  /**************************************************************************
+   *
+   * common functions
+   *
+   */
+
+  /*
+   * Original algorithm:
+   *
+   *   https://github.com/chmike/fpsqrt
+   *
+   * Use this to compute the square root of a 16.16 fixed-point number.
+   */
+  FT_LOCAL_DEF( FT_16D16 )
+  square_root( FT_16D16  val )
+  {
+    FT_ULong  t, q, b, r;
+
+
+    r = (FT_ULong)val;
+    b = 0x40000000L;
+    q = 0;
+
+    while ( b > 0x40L )
+    {
+      t = q + b;
+
+      if ( r >= t )
+      {
+        r -= t;
+        q  = t + b;
+      }
+
+      r <<= 1;
+      b >>= 1;
+    }
+
+    q >>= 8;
+
+    return (FT_16D16)q;
+  }
+
+
+  /**************************************************************************
+   *
+   * format and sign manipulating functions
+   *
+   */
+
+  /*
+   * Convert 16.16 fixed-point values to the desired output format.
+   * In this case we reduce 16.16 fixed-point values to normalized
+   * 8-bit values.
+   *
+   * The `max_value` in the parameter is the maximum value in the
+   * distance field map and is equal to the spread.  We normalize
+   * the distances using this value instead of computing the maximum
+   * value for the entire bitmap.
+   *
+   * You can use this function to map the 16.16 signed values to any
+   * format required.  Do note that the output buffer is 8-bit, so only
+   * use an 8-bit format for `FT_SDFFormat`, or increase the buffer size in
+   * `ftsdfrend.c`.
+   */
+  FT_LOCAL_DEF( FT_SDFFormat )
+  map_fixed_to_sdf( FT_16D16  dist,
+                    FT_16D16  max_value )
+  {
+    FT_SDFFormat  out;
+    FT_16D16      udist;
+
+
+    /* normalize the distance values */
+    dist = FT_DivFix( dist, max_value );
+
+    udist = dist < 0 ? -dist : dist;
+
+    /* Reduce the distance values to 8 bits.                   */
+    /*                                                         */
+    /* Since +1/-1 in 16.16 takes the 16th bit, we right-shift */
+    /* the number by 9 to make it fit into the 7-bit range.    */
+    /*                                                         */
+    /* One bit is reserved for the sign.                       */
+    udist >>= 9;
+
+    /* Since `char` can only store a maximum positive value    */
+    /* of 127 we need to make sure it does not wrap around and */
+    /* give a negative value.                                  */
+    if ( dist > 0 && udist > 127 )
+      udist = 127;
+    if ( dist < 0 && udist > 128 )
+      udist = 128;
+
+    /* Output the data; negative values are from [0, 127] and positive    */
+    /* from [128, 255].  One important thing is that negative values      */
+    /* are inverted here, that means [0, 128] maps to [-128, 0] linearly. */
+    /* More on that in `freetype.h` near the documentation of             */
+    /* `FT_RENDER_MODE_SDF`.                                              */
+    out = dist < 0 ? 128 - (FT_SDFFormat)udist
+                   : (FT_SDFFormat)udist + 128;
+
+    return out;
+  }
+
+
+  /*
+   * Invert the signed distance packed into the corresponding format.
+   * So if the values are negative they will become positive in the
+   * chosen format.
+   *
+   * [Note]: This function should only be used after converting the
+   *         16.16 signed distance values to `FT_SDFFormat`.  If that
+   *         conversion has not been done, then simply invert the sign
+   *         and use the above function to pack the values.
+   */
+  FT_LOCAL_DEF( FT_SDFFormat )
+  invert_sign( FT_SDFFormat  dist )
+  {
+    return 255 - dist;
+  }
+
+
+/* END */