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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 19:33:14 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 19:33:14 +0000 |
commit | 36d22d82aa202bb199967e9512281e9a53db42c9 (patch) | |
tree | 105e8c98ddea1c1e4784a60a5a6410fa416be2de /modules/freetype2/src/psaux/psfont.c | |
parent | Initial commit. (diff) | |
download | firefox-esr-36d22d82aa202bb199967e9512281e9a53db42c9.tar.xz firefox-esr-36d22d82aa202bb199967e9512281e9a53db42c9.zip |
Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'modules/freetype2/src/psaux/psfont.c')
-rw-r--r-- | modules/freetype2/src/psaux/psfont.c | 566 |
1 files changed, 566 insertions, 0 deletions
diff --git a/modules/freetype2/src/psaux/psfont.c b/modules/freetype2/src/psaux/psfont.c new file mode 100644 index 0000000000..0db1f0c5bc --- /dev/null +++ b/modules/freetype2/src/psaux/psfont.c @@ -0,0 +1,566 @@ +/**************************************************************************** + * + * 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 <freetype/internal/ftcalc.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 ) + { + /* check for variation vectors */ + vstore = cf2_getVStore( decoder ); + hasVariations = ( vstore->dataCount != 0 ); + + if ( hasVariations ) + { +#ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT + FT_Service_CFFLoad cffload = (FT_Service_CFFLoad)font->cffload; + + + /* 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 */ |