Work around a behaviour change in freetype > 2.8

Freetype will throw an error when we try to retrieve the glyph if the x/y
advance values are too big to fit in a 16.16 fixed point value.

Since we have no need of those values, set them to zero, and avoid the error.

Bring freetype up to 2.9.1

Plus the gs makefile changes to support the new version.

Reapply "Work around a change in the zlib API for 1.2.11"

for Freetype
commit: 08482c582115a1396d0fd9186011008f889a61c5

1 files changed, 567 insertions, 0 deletions

diff --git a/freetype/src/psaux/psfont.c b/freetype/src/psaux/psfont.c
new file mode 100644
index 000000000..dde67a739
--- /dev/null
+++ b/freetype/src/psaux/psfont.c
@@ -0,0 +1,567 @@
+/***************************************************************************/
+/*                                                                         */
+/*  psfont.c                                                               */
+/*                                                                         */
+/*    Adobe's code for font instances (body).                              */
+/*                                                                         */
+/*  Copyright 2007-2014 Adobe Systems Incorporated.                        */
+/*                                                                         */
+/*  This software, and all works of authorship, whether in source or       */
+/*  object code form as indicated by the copyright notice(s) included      */
+/*  herein (collectively, the "Work") is made available, and may only be   */
+/*  used, modified, and distributed under the FreeType Project License,    */
+/*  LICENSE.TXT.  Additionally, subject to the terms and conditions of the */
+/*  FreeType Project License, each contributor to the Work hereby grants   */
+/*  to any individual or legal entity exercising permissions granted by    */
+/*  the FreeType Project License and this section (hereafter, "You" or     */
+/*  "Your") a perpetual, worldwide, non-exclusive, no-charge,              */
+/*  royalty-free, irrevocable (except as stated in this section) patent    */
+/*  license to make, have made, use, offer to sell, sell, import, and      */
+/*  otherwise transfer the Work, where such license applies only to those  */
+/*  patent claims licensable by such contributor that are necessarily      */
+/*  infringed by their contribution(s) alone or by combination of their    */
+/*  contribution(s) with the Work to which such contribution(s) was        */
+/*  submitted.  If You institute patent litigation against any entity      */
+/*  (including a cross-claim or counterclaim in a lawsuit) alleging that   */
+/*  the Work or a contribution incorporated within the Work constitutes    */
+/*  direct or contributory patent infringement, then any patent licenses   */
+/*  granted to You under this License for that Work shall terminate as of  */
+/*  the date such litigation is filed.                                     */
+/*                                                                         */
+/*  By using, modifying, or distributing the Work you indicate that you    */
+/*  have read and understood the terms and conditions of the               */
+/*  FreeType Project License as well as those provided in this section,    */
+/*  and you accept them fully.                                             */
+/*                                                                         */
+/***************************************************************************/
+
+
+#include <ft2build.h>
+#include FT_INTERNAL_CALC_H
+
+#include "psft.h"
+
+#include "psglue.h"
+#include "psfont.h"
+#include "pserror.h"
+#include "psintrp.h"
+
+
+  /* Compute a stem darkening amount in character space. */
+  static void
+  cf2_computeDarkening( CF2_Fixed   emRatio,
+                        CF2_Fixed   ppem,
+                        CF2_Fixed   stemWidth,
+                        CF2_Fixed*  darkenAmount,
+                        CF2_Fixed   boldenAmount,
+                        FT_Bool     stemDarkened,
+                        FT_Int*     darkenParams )
+  {
+    /*
+     * Total darkening amount is computed in 1000 unit character space
+     * using the modified 5 part curve as Adobe's Avalon rasterizer.
+     * The darkening amount is smaller for thicker stems.
+     * It becomes zero when the stem is thicker than 2.333 pixels.
+     *
+     * By default, we use
+     *
+     *   darkenAmount = 0.4 pixels   if scaledStem <= 0.5 pixels,
+     *   darkenAmount = 0.275 pixels if 1 <= scaledStem <= 1.667 pixels,
+     *   darkenAmount = 0 pixel      if scaledStem >= 2.333 pixels,
+     *
+     * and piecewise linear in-between:
+     *
+     *
+     *   darkening
+     *       ^
+     *       |
+     *       |      (x1,y1)
+     *       |--------+
+     *       |         \
+     *       |          \
+     *       |           \          (x3,y3)
+     *       |            +----------+
+     *       |        (x2,y2)         \
+     *       |                         \
+     *       |                          \
+     *       |                           +-----------------
+     *       |                         (x4,y4)
+     *       +--------------------------------------------->   stem
+     *                                                       thickness
+     *
+     *
+     * This corresponds to the following values for the
+     * `darkening-parameters' property:
+     *
+     *   (x1, y1) = (500, 400)
+     *   (x2, y2) = (1000, 275)
+     *   (x3, y3) = (1667, 275)
+     *   (x4, y4) = (2333, 0)
+     *
+     */
+
+    /* Internal calculations are done in units per thousand for */
+    /* convenience. The x axis is scaled stem width in          */
+    /* thousandths of a pixel. That is, 1000 is 1 pixel.        */
+    /* The y axis is darkening amount in thousandths of a pixel.*/
+    /* In the code, below, dividing by ppem and                 */
+    /* adjusting for emRatio converts darkenAmount to character */
+    /* space (font units).                                      */
+    CF2_Fixed  stemWidthPer1000, scaledStem;
+    FT_Int     logBase2;
+
+
+    *darkenAmount = 0;
+
+    if ( boldenAmount == 0 && !stemDarkened )
+      return;
+
+    /* protect against range problems and divide by zero */
+    if ( emRatio < cf2_doubleToFixed( .01 ) )
+      return;
+
+    if ( stemDarkened )
+    {
+      FT_Int  x1 = darkenParams[0];
+      FT_Int  y1 = darkenParams[1];
+      FT_Int  x2 = darkenParams[2];
+      FT_Int  y2 = darkenParams[3];
+      FT_Int  x3 = darkenParams[4];
+      FT_Int  y3 = darkenParams[5];
+      FT_Int  x4 = darkenParams[6];
+      FT_Int  y4 = darkenParams[7];
+
+
+      /* convert from true character space to 1000 unit character space; */
+      /* add synthetic emboldening effect                                */
+
+      /* `stemWidthPer1000' will not overflow for a legitimate font      */
+
+      stemWidthPer1000 = FT_MulFix( stemWidth + boldenAmount, emRatio );
+
+      /* `scaledStem' can easily overflow, so we must clamp its maximum  */
+      /* value; the test doesn't need to be precise, but must be         */
+      /* conservative.  The clamp value (default 2333) where             */
+      /* `darkenAmount' is zero is well below the overflow value of      */
+      /* 32767.                                                          */
+      /*                                                                 */
+      /* FT_MSB computes the integer part of the base 2 logarithm.  The  */
+      /* number of bits for the product is 1 or 2 more than the sum of   */
+      /* logarithms; remembering that the 16 lowest bits of the fraction */
+      /* are dropped this is correct to within a factor of almost 4.     */
+      /* For example, 0x80.0000 * 0x80.0000 = 0x4000.0000 is 23+23 and   */
+      /* is flagged as possible overflow because 0xFF.FFFF * 0xFF.FFFF = */
+      /* 0xFFFF.FE00 is also 23+23.                                      */
+
+      logBase2 = FT_MSB( (FT_UInt32)stemWidthPer1000 ) +
+                   FT_MSB( (FT_UInt32)ppem );
+
+      if ( logBase2 >= 46 )
+        /* possible overflow */
+        scaledStem = cf2_intToFixed( x4 );
+      else
+        scaledStem = FT_MulFix( stemWidthPer1000, ppem );
+
+      /* now apply the darkening parameters */
+
+      if ( scaledStem < cf2_intToFixed( x1 ) )
+        *darkenAmount = FT_DivFix( cf2_intToFixed( y1 ), ppem );
+
+      else if ( scaledStem < cf2_intToFixed( x2 ) )
+      {
+        FT_Int  xdelta = x2 - x1;
+        FT_Int  ydelta = y2 - y1;
+        FT_Int  x      = stemWidthPer1000 -
+                           FT_DivFix( cf2_intToFixed( x1 ), ppem );
+
+
+        if ( !xdelta )
+          goto Try_x3;
+
+        *darkenAmount = FT_MulDiv( x, ydelta, xdelta ) +
+                          FT_DivFix( cf2_intToFixed( y1 ), ppem );
+      }
+
+      else if ( scaledStem < cf2_intToFixed( x3 ) )
+      {
+      Try_x3:
+        {
+          FT_Int  xdelta = x3 - x2;
+          FT_Int  ydelta = y3 - y2;
+          FT_Int  x      = stemWidthPer1000 -
+                             FT_DivFix( cf2_intToFixed( x2 ), ppem );
+
+
+          if ( !xdelta )
+            goto Try_x4;
+
+          *darkenAmount = FT_MulDiv( x, ydelta, xdelta ) +
+                            FT_DivFix( cf2_intToFixed( y2 ), ppem );
+        }
+      }
+
+      else if ( scaledStem < cf2_intToFixed( x4 ) )
+      {
+      Try_x4:
+        {
+          FT_Int  xdelta = x4 - x3;
+          FT_Int  ydelta = y4 - y3;
+          FT_Int  x      = stemWidthPer1000 -
+                             FT_DivFix( cf2_intToFixed( x3 ), ppem );
+
+
+          if ( !xdelta )
+            goto Use_y4;
+
+          *darkenAmount = FT_MulDiv( x, ydelta, xdelta ) +
+                            FT_DivFix( cf2_intToFixed( y3 ), ppem );
+        }
+      }
+
+      else
+      {
+      Use_y4:
+        *darkenAmount = FT_DivFix( cf2_intToFixed( y4 ), ppem );
+      }
+
+      /* use half the amount on each side and convert back to true */
+      /* character space                                           */
+      *darkenAmount = FT_DivFix( *darkenAmount, 2 * emRatio );
+    }
+
+    /* add synthetic emboldening effect in character space */
+    *darkenAmount += boldenAmount / 2;
+  }
+
+
+  /* set up values for the current FontDict and matrix; */
+  /* called for each glyph to be rendered               */
+
+  /* caller's transform is adjusted for subpixel positioning */
+  static void
+  cf2_font_setup( CF2_Font           font,
+                  const CF2_Matrix*  transform )
+  {
+    /* pointer to parsed font object */
+    PS_Decoder*  decoder = font->decoder;
+
+    FT_Bool  needExtraSetup = FALSE;
+
+    CFF_VStoreRec*  vstore;
+    FT_Bool         hasVariations = FALSE;
+
+    /* character space units */
+    CF2_Fixed  boldenX = font->syntheticEmboldeningAmountX;
+    CF2_Fixed  boldenY = font->syntheticEmboldeningAmountY;
+
+    CFF_SubFont  subFont;
+    CF2_Fixed    ppem;
+
+    CF2_UInt   lenNormalizedV = 0;
+    FT_Fixed*  normalizedV    = NULL;
+
+    /* clear previous error */
+    font->error = FT_Err_Ok;
+
+    /* if a CID fontDict has changed, we need to recompute some cached */
+    /* data                                                            */
+    subFont = cf2_getSubfont( decoder );
+    if ( font->lastSubfont != subFont )
+    {
+      font->lastSubfont = subFont;
+      needExtraSetup    = TRUE;
+    }
+
+    if ( !font->isT1 )
+    {
+      FT_Service_CFFLoad  cffload = (FT_Service_CFFLoad)font->cffload;
+
+
+      /* check for variation vectors */
+      vstore        = cf2_getVStore( decoder );
+      hasVariations = ( vstore->dataCount != 0 );
+
+      if ( hasVariations )
+      {
+#ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT
+        /* check whether Private DICT in this subfont needs to be reparsed */
+        font->error = cf2_getNormalizedVector( decoder,
+                                               &lenNormalizedV,
+                                               &normalizedV );
+        if ( font->error )
+          return;
+
+        if ( cffload->blend_check_vector( &subFont->blend,
+                                          subFont->private_dict.vsindex,
+                                          lenNormalizedV,
+                                          normalizedV ) )
+        {
+          /* blend has changed, reparse */
+          cffload->load_private_dict( decoder->cff,
+                                      subFont,
+                                      lenNormalizedV,
+                                      normalizedV );
+          needExtraSetup = TRUE;
+        }
+#endif
+
+        /* copy from subfont */
+        font->blend.font = subFont->blend.font;
+
+        /* clear state of charstring blend */
+        font->blend.usedBV = FALSE;
+
+        /* initialize value for charstring */
+        font->vsindex = subFont->private_dict.vsindex;
+
+        /* store vector inputs for blends in charstring */
+        font->lenNDV = lenNormalizedV;
+        font->NDV    = normalizedV;
+      }
+    }
+
+    /* if ppem has changed, we need to recompute some cached data         */
+    /* note: because of CID font matrix concatenation, ppem and transform */
+    /*       do not necessarily track.                                    */
+    ppem = cf2_getPpemY( decoder );
+    if ( font->ppem != ppem )
+    {
+      font->ppem     = ppem;
+      needExtraSetup = TRUE;
+    }
+
+    /* copy hinted flag on each call */
+    font->hinted = (FT_Bool)( font->renderingFlags & CF2_FlagsHinted );
+
+    /* determine if transform has changed;       */
+    /* include Fontmatrix but ignore translation */
+    if ( ft_memcmp( transform,
+                    &font->currentTransform,
+                    4 * sizeof ( CF2_Fixed ) ) != 0 )
+    {
+      /* save `key' information for `cache of one' matrix data; */
+      /* save client transform, without the translation         */
+      font->currentTransform    = *transform;
+      font->currentTransform.tx =
+      font->currentTransform.ty = cf2_intToFixed( 0 );
+
+      /* TODO: FreeType transform is simple scalar; for now, use identity */
+      /*       for outer                                                  */
+      font->innerTransform   = *transform;
+      font->outerTransform.a =
+      font->outerTransform.d = cf2_intToFixed( 1 );
+      font->outerTransform.b =
+      font->outerTransform.c = cf2_intToFixed( 0 );
+
+      needExtraSetup = TRUE;
+    }
+
+    /*
+     * font->darkened is set to true if there is a stem darkening request or
+     * the font is synthetic emboldened.
+     * font->darkened controls whether to adjust blue zones, winding order,
+     * and hinting.
+     *
+     */
+    if ( font->stemDarkened != ( font->renderingFlags & CF2_FlagsDarkened ) )
+    {
+      font->stemDarkened =
+        (FT_Bool)( font->renderingFlags & CF2_FlagsDarkened );
+
+      /* blue zones depend on darkened flag */
+      needExtraSetup = TRUE;
+    }
+
+    /* recompute variables that are dependent on transform or FontDict or */
+    /* darken flag                                                        */
+    if ( needExtraSetup )
+    {
+      /* StdVW is found in the private dictionary;                       */
+      /* recompute darkening amounts whenever private dictionary or      */
+      /* transform change                                                */
+      /* Note: a rendering flag turns darkening on or off, so we want to */
+      /*       store the `on' amounts;                                   */
+      /*       darkening amount is computed in character space           */
+      /* TODO: testing size-dependent darkening here;                    */
+      /*       what to do for rotations?                                 */
+
+      CF2_Fixed  emRatio;
+      CF2_Fixed  stdHW;
+      CF2_Int    unitsPerEm = font->unitsPerEm;
+
+
+      if ( unitsPerEm == 0 )
+        unitsPerEm = 1000;
+
+      ppem = FT_MAX( cf2_intToFixed( 4 ),
+                     font->ppem ); /* use minimum ppem of 4 */
+
+#if 0
+      /* since vstem is measured in the x-direction, we use the `a' member */
+      /* of the fontMatrix                                                 */
+      emRatio = cf2_fixedFracMul( cf2_intToFixed( 1000 ), fontMatrix->a );
+#endif
+
+      /* Freetype does not preserve the fontMatrix when parsing; use */
+      /* unitsPerEm instead.                                         */
+      /* TODO: check precision of this                               */
+      emRatio     = cf2_intToFixed( 1000 ) / unitsPerEm;
+      font->stdVW = cf2_getStdVW( decoder );
+
+      if ( font->stdVW <= 0 )
+        font->stdVW = FT_DivFix( cf2_intToFixed( 75 ), emRatio );
+
+      if ( boldenX > 0 )
+      {
+        /* Ensure that boldenX is at least 1 pixel for synthetic bold font */
+        /* (similar to what Avalon does)                                   */
+        boldenX = FT_MAX( boldenX,
+                          FT_DivFix( cf2_intToFixed( unitsPerEm ), ppem ) );
+
+        /* Synthetic emboldening adds at least 1 pixel to darkenX, while */
+        /* stem darkening adds at most half pixel.  Since the purpose of */
+        /* stem darkening (readability at small sizes) is met with       */
+        /* synthetic emboldening, no need to add stem darkening for a    */
+        /* synthetic bold font.                                          */
+        cf2_computeDarkening( emRatio,
+                              ppem,
+                              font->stdVW,
+                              &font->darkenX,
+                              boldenX,
+                              FALSE,
+                              font->darkenParams );
+      }
+      else
+        cf2_computeDarkening( emRatio,
+                              ppem,
+                              font->stdVW,
+                              &font->darkenX,
+                              0,
+                              font->stemDarkened,
+                              font->darkenParams );
+
+#if 0
+      /* since hstem is measured in the y-direction, we use the `d' member */
+      /* of the fontMatrix                                                 */
+      /* TODO: use the same units per em as above; check this              */
+      emRatio = cf2_fixedFracMul( cf2_intToFixed( 1000 ), fontMatrix->d );
+#endif
+
+      /* set the default stem width, because it must be the same for all */
+      /* family members;                                                 */
+      /* choose a constant for StdHW that depends on font contrast       */
+      stdHW = cf2_getStdHW( decoder );
+
+      if ( stdHW > 0 && font->stdVW > MUL_INT32( 2, stdHW ) )
+        font->stdHW = FT_DivFix( cf2_intToFixed( 75 ), emRatio );
+      else
+      {
+        /* low contrast font gets less hstem darkening */
+        font->stdHW = FT_DivFix( cf2_intToFixed( 110 ), emRatio );
+      }
+
+      cf2_computeDarkening( emRatio,
+                            ppem,
+                            font->stdHW,
+                            &font->darkenY,
+                            boldenY,
+                            font->stemDarkened,
+                            font->darkenParams );
+
+      if ( font->darkenX != 0 || font->darkenY != 0 )
+        font->darkened = TRUE;
+      else
+        font->darkened = FALSE;
+
+      font->reverseWinding = FALSE; /* initial expectation is CCW */
+
+      /* compute blue zones for this instance */
+      cf2_blues_init( &font->blues, font );
+
+    } /* needExtraSetup */
+  }
+
+
+  /* equivalent to AdobeGetOutline */
+  FT_LOCAL_DEF( FT_Error )
+  cf2_getGlyphOutline( CF2_Font           font,
+                       CF2_Buffer         charstring,
+                       const CF2_Matrix*  transform,
+                       CF2_F16Dot16*      glyphWidth )
+  {
+    FT_Error  lastError = FT_Err_Ok;
+
+    FT_Vector  translation;
+
+#if 0
+    FT_Vector  advancePoint;
+#endif
+
+    CF2_Fixed  advWidth = 0;
+    FT_Bool    needWinding;
+
+
+    /* Note: use both integer and fraction for outlines.  This allows bbox */
+    /*       to come out directly.                                         */
+
+    translation.x = transform->tx;
+    translation.y = transform->ty;
+
+    /* set up values based on transform */
+    cf2_font_setup( font, transform );
+    if ( font->error )
+      goto exit;                      /* setup encountered an error */
+
+    /* reset darken direction */
+    font->reverseWinding = FALSE;
+
+    /* winding order only affects darkening */
+    needWinding = font->darkened;
+
+    while ( 1 )
+    {
+      /* reset output buffer */
+      cf2_outline_reset( &font->outline );
+
+      /* build the outline, passing the full translation */
+      cf2_interpT2CharString( font,
+                              charstring,
+                              (CF2_OutlineCallbacks)&font->outline,
+                              &translation,
+                              FALSE,
+                              0,
+                              0,
+                              &advWidth );
+
+      if ( font->error )
+        goto exit;
+
+      if ( !needWinding )
+        break;
+
+      /* check winding order */
+      if ( font->outline.root.windingMomentum >= 0 ) /* CFF is CCW */
+        break;
+
+      /* invert darkening and render again                            */
+      /* TODO: this should be a parameter to getOutline-computeOffset */
+      font->reverseWinding = TRUE;
+
+      needWinding = FALSE;    /* exit after next iteration */
+    }
+
+    /* finish storing client outline */
+    cf2_outline_close( &font->outline );
+
+  exit:
+    /* FreeType just wants the advance width; there is no translation */
+    *glyphWidth = advWidth;
+
+    /* free resources and collect errors from objects we've used */
+    cf2_setError( &font->error, lastError );
+
+    return font->error;
+  }
+
+
+/* END */