| /** | |
| * Copyright (C) 2003, 2006 Apple Computer, Inc. | |
| * Copyright (C) 2008 Holger Hans Peter Freyther | |
| * Copyright (C) 2009 Torch Mobile, Inc. | |
| * | |
| * This library is free software; you can redistribute it and/or | |
| * modify it under the terms of the GNU Library General Public | |
| * License as published by the Free Software Foundation; either | |
| * version 2 of the License, or (at your option) any later version. | |
| * | |
| * This library is distributed in the hope that it will be useful, | |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| * Library General Public License for more details. | |
| * | |
| * You should have received a copy of the GNU Library General Public License | |
| * along with this library; see the file COPYING.LIB. If not, write to | |
| * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, | |
| * Boston, MA 02110-1301, USA. | |
| * | |
| */ | |
| #include "config.h" | |
| #include "Font.h" | |
| #include "CharacterNames.h" | |
| #include "FloatRect.h" | |
| #include "FontCache.h" | |
| #include "FontFallbackList.h" | |
| #include "GlyphBuffer.h" | |
| #include "GlyphPageTreeNode.h" | |
| #include "IntPoint.h" | |
| #include "SimpleFontData.h" | |
| #include "WidthIterator.h" | |
| #include <wtf/MathExtras.h> | |
| #include <wtf/unicode/Unicode.h> | |
| using namespace WTF; | |
| using namespace Unicode; | |
| namespace WebCore { | |
| GlyphData Font::glyphDataForCharacter(UChar32 c, bool mirror, bool forceSmallCaps) const | |
| { | |
| ASSERT(isMainThread()); | |
| bool useSmallCapsFont = forceSmallCaps; | |
| if (m_fontDescription.smallCaps()) { | |
| UChar32 upperC = toUpper(c); | |
| if (upperC != c) { | |
| c = upperC; | |
| useSmallCapsFont = true; | |
| } | |
| } | |
| if (mirror) | |
| c = mirroredChar(c); | |
| unsigned pageNumber = (c / GlyphPage::size); | |
| GlyphPageTreeNode* node = pageNumber ? m_fontList->m_pages.get(pageNumber) : m_fontList->m_pageZero; | |
| if (!node) { | |
| node = GlyphPageTreeNode::getRootChild(fontDataAt(0), pageNumber); | |
| if (pageNumber) | |
| m_fontList->m_pages.set(pageNumber, node); | |
| else | |
| m_fontList->m_pageZero = node; | |
| } | |
| GlyphPage* page; | |
| if (!useSmallCapsFont) { | |
| // Fastest loop, for the common case (not small caps). | |
| while (true) { | |
| page = node->page(); | |
| if (page) { | |
| GlyphData data = page->glyphDataForCharacter(c); | |
| if (data.fontData) | |
| return data; | |
| if (node->isSystemFallback()) | |
| break; | |
| } | |
| // Proceed with the fallback list. | |
| node = node->getChild(fontDataAt(node->level()), pageNumber); | |
| if (pageNumber) | |
| m_fontList->m_pages.set(pageNumber, node); | |
| else | |
| m_fontList->m_pageZero = node; | |
| } | |
| } else { | |
| while (true) { | |
| page = node->page(); | |
| if (page) { | |
| GlyphData data = page->glyphDataForCharacter(c); | |
| if (data.fontData) { | |
| // The smallCapsFontData function should not normally return 0. | |
| // But if it does, we will just render the capital letter big. | |
| const SimpleFontData* smallCapsFontData = data.fontData->smallCapsFontData(m_fontDescription); | |
| if (!smallCapsFontData) | |
| return data; | |
| GlyphPageTreeNode* smallCapsNode = GlyphPageTreeNode::getRootChild(smallCapsFontData, pageNumber); | |
| const GlyphPage* smallCapsPage = smallCapsNode->page(); | |
| if (smallCapsPage) { | |
| GlyphData data = smallCapsPage->glyphDataForCharacter(c); | |
| if (data.fontData) | |
| return data; | |
| } | |
| // Do not attempt system fallback off the smallCapsFontData. This is the very unlikely case that | |
| // a font has the lowercase character but the small caps font does not have its uppercase version. | |
| return smallCapsFontData->missingGlyphData(); | |
| } | |
| if (node->isSystemFallback()) | |
| break; | |
| } | |
| // Proceed with the fallback list. | |
| node = node->getChild(fontDataAt(node->level()), pageNumber); | |
| if (pageNumber) | |
| m_fontList->m_pages.set(pageNumber, node); | |
| else | |
| m_fontList->m_pageZero = node; | |
| } | |
| } | |
| ASSERT(page); | |
| ASSERT(node->isSystemFallback()); | |
| // System fallback is character-dependent. When we get here, we | |
| // know that the character in question isn't in the system fallback | |
| // font's glyph page. Try to lazily create it here. | |
| UChar codeUnits[2]; | |
| int codeUnitsLength; | |
| if (c <= 0xFFFF) { | |
| codeUnits[0] = Font::normalizeSpaces(c); | |
| codeUnitsLength = 1; | |
| } else { | |
| codeUnits[0] = U16_LEAD(c); | |
| codeUnits[1] = U16_TRAIL(c); | |
| codeUnitsLength = 2; | |
| } | |
| const SimpleFontData* characterFontData = fontCache()->getFontDataForCharacters(*this, codeUnits, codeUnitsLength); | |
| if (useSmallCapsFont && characterFontData) | |
| characterFontData = characterFontData->smallCapsFontData(m_fontDescription); | |
| if (characterFontData) { | |
| // Got the fallback glyph and font. | |
| GlyphPage* fallbackPage = GlyphPageTreeNode::getRootChild(characterFontData, pageNumber)->page(); | |
| GlyphData data = fallbackPage && fallbackPage->fontDataForCharacter(c) ? fallbackPage->glyphDataForCharacter(c) : characterFontData->missingGlyphData(); | |
| // Cache it so we don't have to do system fallback again next time. | |
| if (!useSmallCapsFont) { | |
| #if OS(WINCE) | |
| // missingGlyphData returns a null character, which is not suitable for GDI to display. | |
| // Also, sometimes we cannot map a font for the character on WINCE, but GDI can still | |
| // display the character, probably because the font package is not installed correctly. | |
| // So we just always set the glyph to be same as the character, and let GDI solve it. | |
| page->setGlyphDataForCharacter(c, c, characterFontData); | |
| return page->glyphDataForCharacter(c); | |
| #else | |
| page->setGlyphDataForCharacter(c, data.glyph, data.fontData); | |
| #endif | |
| } | |
| return data; | |
| } | |
| // Even system fallback can fail; use the missing glyph in that case. | |
| // FIXME: It would be nicer to use the missing glyph from the last resort font instead. | |
| GlyphData data = primaryFont()->missingGlyphData(); | |
| if (!useSmallCapsFont) { | |
| #if OS(WINCE) | |
| // See comment about WINCE GDI handling near setGlyphDataForCharacter above. | |
| page->setGlyphDataForCharacter(c, c, data.fontData); | |
| return page->glyphDataForCharacter(c); | |
| #else | |
| page->setGlyphDataForCharacter(c, data.glyph, data.fontData); | |
| #endif | |
| } | |
| return data; | |
| } | |
| void Font::drawSimpleText(GraphicsContext* context, const TextRun& run, const FloatPoint& point, int from, int to) const | |
| { | |
| // This glyph buffer holds our glyphs+advances+font data for each glyph. | |
| GlyphBuffer glyphBuffer; | |
| float startX = point.x(); | |
| WidthIterator it(this, run); | |
| it.advance(from); | |
| float beforeWidth = it.m_runWidthSoFar; | |
| it.advance(to, &glyphBuffer); | |
| // We couldn't generate any glyphs for the run. Give up. | |
| if (glyphBuffer.isEmpty()) | |
| return; | |
| float afterWidth = it.m_runWidthSoFar; | |
| if (run.rtl()) { | |
| float finalRoundingWidth = it.m_finalRoundingWidth; | |
| it.advance(run.length()); | |
| startX += finalRoundingWidth + it.m_runWidthSoFar - afterWidth; | |
| } else | |
| startX += beforeWidth; | |
| // Swap the order of the glyphs if right-to-left. | |
| if (run.rtl()) | |
| for (int i = 0, end = glyphBuffer.size() - 1; i < glyphBuffer.size() / 2; ++i, --end) | |
| glyphBuffer.swap(i, end); | |
| // Calculate the starting point of the glyphs to be displayed by adding | |
| // all the advances up to the first glyph. | |
| FloatPoint startPoint(startX, point.y()); | |
| drawGlyphBuffer(context, glyphBuffer, run, startPoint); | |
| } | |
| void Font::drawGlyphBuffer(GraphicsContext* context, const GlyphBuffer& glyphBuffer, const TextRun&, const FloatPoint& point) const | |
| { | |
| // Draw each contiguous run of glyphs that use the same font data. | |
| const SimpleFontData* fontData = glyphBuffer.fontDataAt(0); | |
| FloatSize offset = glyphBuffer.offsetAt(0); | |
| FloatPoint startPoint(point); | |
| float nextX = startPoint.x(); | |
| int lastFrom = 0; | |
| int nextGlyph = 0; | |
| while (nextGlyph < glyphBuffer.size()) { | |
| const SimpleFontData* nextFontData = glyphBuffer.fontDataAt(nextGlyph); | |
| FloatSize nextOffset = glyphBuffer.offsetAt(nextGlyph); | |
| if (nextFontData != fontData || nextOffset != offset) { | |
| drawGlyphs(context, fontData, glyphBuffer, lastFrom, nextGlyph - lastFrom, startPoint); | |
| lastFrom = nextGlyph; | |
| fontData = nextFontData; | |
| offset = nextOffset; | |
| startPoint.setX(nextX); | |
| } | |
| nextX += glyphBuffer.advanceAt(nextGlyph); | |
| nextGlyph++; | |
| } | |
| drawGlyphs(context, fontData, glyphBuffer, lastFrom, nextGlyph - lastFrom, startPoint); | |
| } | |
| float Font::floatWidthForSimpleText(const TextRun& run, GlyphBuffer* glyphBuffer, HashSet<const SimpleFontData*>* fallbackFonts, GlyphOverflow* glyphOverflow) const | |
| { | |
| WidthIterator it(this, run, fallbackFonts, glyphOverflow); | |
| it.advance(run.length(), glyphBuffer); | |
| if (glyphOverflow) { | |
| glyphOverflow->top = max<int>(glyphOverflow->top, ceilf(-it.minGlyphBoundingBoxY()) - ascent()); | |
| glyphOverflow->bottom = max<int>(glyphOverflow->bottom, ceilf(it.maxGlyphBoundingBoxY()) - descent()); | |
| glyphOverflow->left = ceilf(it.firstGlyphOverflow()); | |
| glyphOverflow->right = ceilf(it.lastGlyphOverflow()); | |
| } | |
| return it.m_runWidthSoFar; | |
| } | |
| FloatRect Font::selectionRectForSimpleText(const TextRun& run, const IntPoint& point, int h, int from, int to) const | |
| { | |
| WidthIterator it(this, run); | |
| it.advance(from); | |
| float beforeWidth = it.m_runWidthSoFar; | |
| it.advance(to); | |
| float afterWidth = it.m_runWidthSoFar; | |
| // Using roundf() rather than ceilf() for the right edge as a compromise to ensure correct caret positioning | |
| if (run.rtl()) { | |
| it.advance(run.length()); | |
| float totalWidth = it.m_runWidthSoFar; | |
| return FloatRect(point.x() + floorf(totalWidth - afterWidth), point.y(), roundf(totalWidth - beforeWidth) - floorf(totalWidth - afterWidth), h); | |
| } else { | |
| return FloatRect(point.x() + floorf(beforeWidth), point.y(), roundf(afterWidth) - floorf(beforeWidth), h); | |
| } | |
| } | |
| int Font::offsetForPositionForSimpleText(const TextRun& run, int x, bool includePartialGlyphs) const | |
| { | |
| float delta = (float)x; | |
| WidthIterator it(this, run); | |
| GlyphBuffer localGlyphBuffer; | |
| unsigned offset; | |
| if (run.rtl()) { | |
| delta -= floatWidthForSimpleText(run, 0); | |
| while (1) { | |
| offset = it.m_currentCharacter; | |
| float w; | |
| if (!it.advanceOneCharacter(w, &localGlyphBuffer)) | |
| break; | |
| delta += w; | |
| if (includePartialGlyphs) { | |
| if (delta - w / 2 >= 0) | |
| break; | |
| } else { | |
| if (delta >= 0) | |
| break; | |
| } | |
| } | |
| } else { | |
| while (1) { | |
| offset = it.m_currentCharacter; | |
| float w; | |
| if (!it.advanceOneCharacter(w, &localGlyphBuffer)) | |
| break; | |
| delta -= w; | |
| if (includePartialGlyphs) { | |
| if (delta + w / 2 <= 0) | |
| break; | |
| } else { | |
| if (delta <= 0) | |
| break; | |
| } | |
| } | |
| } | |
| return offset; | |
| } | |
| } |