diff options
Diffstat (limited to 'Source/WebCore/platform/graphics/chromium/UniscribeHelper.cpp')
| -rw-r--r-- | Source/WebCore/platform/graphics/chromium/UniscribeHelper.cpp | 114 |
1 files changed, 68 insertions, 46 deletions
diff --git a/Source/WebCore/platform/graphics/chromium/UniscribeHelper.cpp b/Source/WebCore/platform/graphics/chromium/UniscribeHelper.cpp index dda84a9..524beec 100644 --- a/Source/WebCore/platform/graphics/chromium/UniscribeHelper.cpp +++ b/Source/WebCore/platform/graphics/chromium/UniscribeHelper.cpp @@ -31,45 +31,16 @@ #include "config.h" #include "UniscribeHelper.h" -#include <windows.h> - +#include "Font.h" #include "FontUtilsChromiumWin.h" #include "PlatformContextSkia.h" #include "SkiaFontWin.h" #include "SkPoint.h" +#include <windows.h> #include <wtf/Assertions.h> namespace WebCore { -// This function is used to see where word spacing should be applied inside -// runs. Note that this must match Font::treatAsSpace so we all agree where -// and how much space this is, so we don't want to do more general Unicode -// "is this a word break" thing. -static bool treatAsSpace(UChar c) -{ - return c == ' ' || c == '\t' || c == '\n' || c == 0x00A0; -} - -// SCRIPT_FONTPROPERTIES contains glyph indices for default, invalid -// and blank glyphs. Just because ScriptShape succeeds does not mean -// that a text run is rendered correctly. Some characters may be rendered -// with default/invalid/blank glyphs. Therefore, we need to check if the glyph -// array returned by ScriptShape contains any of those glyphs to make -// sure that the text run is rendered successfully. -static bool containsMissingGlyphs(WORD *glyphs, - int length, - SCRIPT_FONTPROPERTIES* properties) -{ - for (int i = 0; i < length; ++i) { - if (glyphs[i] == properties->wgDefault - || (glyphs[i] == properties->wgInvalid - && glyphs[i] != properties->wgBlank)) - return true; - } - - return false; -} - // HFONT is the 'incarnation' of 'everything' about font, but it's an opaque // handle and we can't directly query it to make a new HFONT sharing // its characteristics (height, style, etc) except for family name. @@ -102,13 +73,15 @@ UniscribeHelper::UniscribeHelper(const UChar* input, bool isRtl, HFONT hfont, SCRIPT_CACHE* scriptCache, - SCRIPT_FONTPROPERTIES* fontProperties) + SCRIPT_FONTPROPERTIES* fontProperties, + WORD spaceGlyph) : m_input(input) , m_inputLength(inputLength) , m_isRtl(isRtl) , m_hfont(hfont) , m_scriptCache(scriptCache) , m_fontProperties(fontProperties) + , m_spaceGlyph(spaceGlyph) , m_directionalOverride(false) , m_inhibitLigate(false) , m_letterSpacing(0) @@ -546,6 +519,7 @@ bool UniscribeHelper::shape(const UChar* input, SCRIPT_CACHE* scriptCache = m_scriptCache; SCRIPT_FONTPROPERTIES* fontProperties = m_fontProperties; int ascent = m_ascent; + WORD spaceGlyph = m_spaceGlyph; HDC tempDC = 0; HGDIOBJ oldFont = 0; HRESULT hr; @@ -601,7 +575,7 @@ bool UniscribeHelper::shape(const UChar* input, } else if (hr == E_OUTOFMEMORY) { numGlyphs *= 2; continue; - } else if (SUCCEEDED(hr) && (lastFallbackTried || !containsMissingGlyphs(&shaping.m_glyphs[0], generatedGlyphs, fontProperties))) + } else if (SUCCEEDED(hr) && (lastFallbackTried || !containsMissingGlyphs(shaping, run, fontProperties))) break; // The current font can't render this run. clear DC and try @@ -632,7 +606,9 @@ bool UniscribeHelper::shape(const UChar* input, const UChar *family = getFallbackFamily(input, itemLength, FontDescription::StandardFamily, 0, 0); bool fontOk = getDerivedFontData(family, m_style, &m_logfont, - &ascent, &hfont, &scriptCache); + &ascent, &hfont, &scriptCache, + &spaceGlyph); + if (!fontOk) { // If this GetDerivedFontData is called from the renderer it @@ -644,7 +620,8 @@ bool UniscribeHelper::shape(const UChar* input, // Try again. fontOk = getDerivedFontData(family, m_style, &m_logfont, - &ascent, &hfont, &scriptCache); + &ascent, &hfont, &scriptCache, + &spaceGlyph); ASSERT(fontOk); } @@ -673,6 +650,7 @@ bool UniscribeHelper::shape(const UChar* input, // because it's not used elsewhere. shaping.m_hfont = hfont; shaping.m_scriptCache = scriptCache; + shaping.m_spaceGlyph = spaceGlyph; // The ascent of a font for this run can be different from // that of the primary font so that we need to keep track of @@ -806,22 +784,39 @@ void UniscribeHelper::adjustSpaceAdvances() for (size_t run = 0; run < m_runs.size(); run++) { Shaping& shaping = m_shapes[run]; + // FIXME: This loop is not UTF-16-safe. Unicode 6.0 has a couple + // of complex script blocks in Plane 1. for (int i = 0; i < shaping.charLength(); i++) { - if (!treatAsSpace(m_input[m_runs[run].iCharPos + i])) + UChar c = m_input[m_runs[run].iCharPos + i]; + bool treatAsSpace = Font::treatAsSpace(c); + if (!treatAsSpace && !Font::treatAsZeroWidthSpaceInComplexScript(c)) continue; int glyphIndex = shaping.m_logs[i]; int currentAdvance = shaping.m_advance[glyphIndex]; - // currentAdvance does not include additional letter-spacing, but - // space_width does. Here we find out how off we are from the - // correct width for the space not including letter-spacing, then - // just subtract that diff. - int diff = currentAdvance - spaceWidthWithoutLetterSpacing; - // The shaping can consist of a run of text, so only subtract the - // difference in the width of the glyph. - shaping.m_advance[glyphIndex] -= diff; - shaping.m_abc.abcB -= diff; + if (treatAsSpace) { + // currentAdvance does not include additional letter-spacing, + // but m_spaceWidth does. Here we find out how off we are from + // the correct width (spaceWidthWithoutLetterSpacing) and + // just subtract that diff. + int diff = currentAdvance - spaceWidthWithoutLetterSpacing; + // The shaping can consist of a run of text, so only subtract + // the difference in the width of the glyph. + shaping.m_advance[glyphIndex] -= diff; + shaping.m_abc.abcB -= diff; + continue; + } + + // For characters treated as zero-width space in complex + // scripts, set the advance width to zero, adjust + // |abcB| of the current run accordingly and set + // the glyph to m_spaceGlyph (invisible). + shaping.m_advance[glyphIndex] = 0; + shaping.m_abc.abcB -= currentAdvance; + shaping.m_offsets[glyphIndex].du = 0; + shaping.m_offsets[glyphIndex].dv = 0; + shaping.m_glyphs[glyphIndex] = shaping.m_spaceGlyph; } } } @@ -872,7 +867,7 @@ void UniscribeHelper::applySpacing() // extra wordspacing amount for the glyphs they correspond to. if (m_wordSpacing != 0) { for (int i = 0; i < shaping.charLength(); i++) { - if (!treatAsSpace(m_input[m_runs[run].iCharPos + i])) + if (!Font::treatAsSpace(m_input[m_runs[run].iCharPos + i])) continue; // The char in question is a word separator... @@ -929,4 +924,31 @@ int UniscribeHelper::advanceForItem(int itemIndex) const return shaping.m_prePadding + justification; } +// SCRIPT_FONTPROPERTIES contains glyph indices for default, invalid +// and blank glyphs. Just because ScriptShape succeeds does not mean +// that a text run is rendered correctly. Some characters may be rendered +// with default/invalid/blank glyphs. Therefore, we need to check if the glyph +// array returned by ScriptShape contains any of those glyphs to make +// sure that the text run is rendered successfully. +// However, we should not subject zero-width characters to this test. + +bool UniscribeHelper::containsMissingGlyphs(const Shaping& shaping, + const SCRIPT_ITEM& run, + const SCRIPT_FONTPROPERTIES* properties) const +{ + for (int i = 0; i < shaping.charLength(); i++) { + UChar c = m_input[run.iCharPos + i]; + // Skip zero-width space characters because they're not considered to be missing in a font. + if (Font::treatAsZeroWidthSpaceInComplexScript(c)) + continue; + int glyphIndex = shaping.m_logs[i]; + WORD glyph = shaping.m_glyphs[glyphIndex]; + if (glyph == properties->wgDefault + || (glyph == properties->wgInvalid && glyph != properties->wgBlank)) + return true; + } + return false; +} + + } // namespace WebCore |