| /* |
| * Copyright (C) 2007 Apple Inc. All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * 3. Neither the name of Apple Computer, Inc. ("Apple") nor the names of |
| * its contributors may be used to endorse or promote products derived |
| * from this software without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY |
| * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED |
| * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE |
| * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY |
| * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES |
| * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
| * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND |
| * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
| * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| #include "config.h" |
| #include "UniscribeController.h" |
| #include "Font.h" |
| #include "FontData.h" |
| #include "TextStyle.h" |
| #include <wtf/MathExtras.h> |
| |
| namespace WebCore { |
| |
| // FIXME: Rearchitect this to be more like WidthIterator in Font.cpp. Have an advance() method |
| // that does stuff in that method instead of doing everything in the constructor. Have advance() |
| // take the GlyphBuffer as an arg so that we don't have to populate the glyph buffer when |
| // measuring. |
| UniscribeController::UniscribeController(const Font* font, const TextRun& run, const TextStyle& style) |
| : m_font(*font) |
| , m_run(run) |
| , m_style(style) |
| , m_end(run.length()) |
| , m_currentCharacter(0) |
| , m_runWidthSoFar(0) |
| , m_computingOffsetPosition(false) |
| , m_includePartialGlyphs(false) |
| , m_offsetX(0) |
| , m_offsetPosition(0) |
| { |
| m_padding = m_style.padding(); |
| if (!m_padding) |
| m_padPerSpace = 0; |
| else { |
| float numSpaces = 0; |
| for (int s = 0; s < m_run.length(); s++) |
| if (Font::treatAsSpace(m_run[s])) |
| numSpaces++; |
| |
| if (numSpaces == 0) |
| m_padPerSpace = 0; |
| else |
| m_padPerSpace = ceilf(m_style.padding() / numSpaces); |
| } |
| |
| // Null out our uniscribe structs |
| resetControlAndState(); |
| } |
| |
| int UniscribeController::offsetForPosition(int x, bool includePartialGlyphs) |
| { |
| m_computingOffsetPosition = true; |
| m_includePartialGlyphs = includePartialGlyphs; |
| m_offsetX = x; |
| m_offsetPosition = 0; |
| advance(m_run.length()); |
| if (m_computingOffsetPosition) { |
| // The point is to the left or to the right of the entire run. |
| if (m_offsetX >= m_runWidthSoFar && m_style.ltr() || m_offsetX < 0 && m_style.rtl()) |
| m_offsetPosition = m_end; |
| } |
| m_computingOffsetPosition = false; |
| return m_offsetPosition; |
| } |
| |
| void UniscribeController::advance(unsigned offset, GlyphBuffer* glyphBuffer) |
| { |
| // FIXME: We really want to be using a newer version of Uniscribe that supports the new OpenType |
| // functions. Those functions would allow us to turn off kerning and ligatures. Without being able |
| // to do that, we will have buggy line breaking and metrics when simple and complex text are close |
| // together (the complex code path will narrow the text because of kerning and ligatures and then |
| // when bidi processing splits into multiple runs, the simple portions will get wider and cause us to |
| // spill off the edge of a line). |
| if (static_cast<int>(offset) > m_end) |
| offset = m_end; |
| |
| // Itemize the string. |
| const UChar* cp = m_run.data(m_currentCharacter); |
| int length = offset - m_currentCharacter; |
| if (length <= 0) |
| return; |
| |
| // We break up itemization of the string if small caps is involved. |
| // Adjust the characters to account for small caps if it is set. |
| if (m_font.isSmallCaps()) { |
| // FIXME: It's inconsistent that we use logical order when itemizing, since this |
| // does not match normal RTL. |
| Vector<UChar> smallCapsBuffer(length); |
| memcpy(smallCapsBuffer.data(), cp, length * sizeof(UChar)); |
| bool isSmallCaps = false; |
| unsigned indexOfCaseShift = m_style.rtl() ? length - 1 : 0; |
| const UChar* curr = m_style.rtl() ? cp + length - 1: cp; |
| const UChar* end = m_style.rtl() ? cp - 1: cp + length; |
| while (curr != end) { |
| int index = curr - cp; |
| UChar c = smallCapsBuffer[index]; |
| UChar newC; |
| curr = m_style.rtl() ? curr - 1 : curr + 1; |
| if (U_GET_GC_MASK(c) & U_GC_M_MASK) |
| continue; |
| if (!u_isUUppercase(c) && (newC = u_toupper(c)) != c) { |
| smallCapsBuffer[index] = newC; |
| if (!isSmallCaps) { |
| isSmallCaps = true; |
| int itemStart = m_style.rtl() ? index : indexOfCaseShift; |
| int itemLength = m_style.rtl() ? indexOfCaseShift - index : index - indexOfCaseShift; |
| itemizeShapeAndPlace(smallCapsBuffer.data() + itemStart, itemLength, false, glyphBuffer); |
| indexOfCaseShift = index; |
| } |
| } else if (isSmallCaps) { |
| isSmallCaps = false; |
| int itemStart = m_style.rtl() ? index : indexOfCaseShift; |
| int itemLength = m_style.rtl() ? indexOfCaseShift - index : index - indexOfCaseShift; |
| itemizeShapeAndPlace(smallCapsBuffer.data() + itemStart, itemLength, true, glyphBuffer); |
| indexOfCaseShift = index; |
| } |
| } |
| |
| int itemLength = m_style.rtl() ? indexOfCaseShift + 1 : length - indexOfCaseShift; |
| if (itemLength) { |
| int itemStart = m_style.rtl() ? 0 : indexOfCaseShift; |
| itemizeShapeAndPlace(smallCapsBuffer.data() + itemStart, itemLength, isSmallCaps, glyphBuffer); |
| } |
| } else |
| itemizeShapeAndPlace(cp, length, false, glyphBuffer); |
| } |
| |
| void UniscribeController::itemizeShapeAndPlace(const UChar* cp, unsigned length, bool smallCaps, GlyphBuffer* glyphBuffer) |
| { |
| // ScriptItemize (in Windows XP versions prior to SP2) can overflow by 1. This is why there is an extra empty item |
| // hanging out at the end of the array |
| m_items.resize(6); |
| int numItems = 0; |
| while (ScriptItemize(cp, length, m_items.size() - 1, &m_control, &m_state, m_items.data(), &numItems) == E_OUTOFMEMORY) { |
| m_items.resize(m_items.size() * 2); |
| resetControlAndState(); |
| } |
| m_items.resize(numItems + 1); |
| |
| if (m_style.rtl()) { |
| for (int i = m_items.size() - 2; i >= 0; i--) { |
| if (!shapeAndPlaceItem(cp, i, smallCaps, glyphBuffer)) |
| return; |
| } |
| } else { |
| for (unsigned i = 0; i < m_items.size() - 1; i++) { |
| if (!shapeAndPlaceItem(cp, i, smallCaps, glyphBuffer)) |
| return; |
| } |
| } |
| |
| m_currentCharacter += length; |
| } |
| |
| void UniscribeController::resetControlAndState() |
| { |
| memset(&m_control, 0, sizeof(SCRIPT_CONTROL)); |
| memset(&m_state, 0, sizeof(SCRIPT_STATE)); |
| |
| // Set up the correct direction for the run. |
| m_state.uBidiLevel = m_style.rtl(); |
| |
| // Lock the correct directional override. |
| m_state.fOverrideDirection = m_style.directionalOverride(); |
| } |
| |
| bool UniscribeController::shapeAndPlaceItem(const UChar* cp, unsigned i, bool smallCaps, GlyphBuffer* glyphBuffer) |
| { |
| // Determine the string for this item. |
| const UChar* str = cp + m_items[i].iCharPos; |
| int len = m_items[i+1].iCharPos - m_items[i].iCharPos; |
| SCRIPT_ITEM item = m_items[i]; |
| |
| // Get our current FontData that we are using. |
| unsigned dataIndex = 0; |
| const FontData* fontData = m_font.fontDataAt(dataIndex); |
| if (smallCaps) |
| fontData = fontData->smallCapsFontData(m_font.fontDescription()); |
| |
| // Set up buffers to hold the results of shaping the item. |
| Vector<WORD> glyphs; |
| Vector<WORD> clusters; |
| Vector<SCRIPT_VISATTR> visualAttributes; |
| clusters.resize(len); |
| |
| // Shape the item. This will provide us with glyphs for the item. We will |
| // attempt to shape using the first available FontData. If the shaping produces a result with missing |
| // glyphs, then we will fall back to the next FontData. |
| // FIXME: This isn't as good as per-glyph fallback, but in practice it should be pretty good, since |
| // items are broken up by "shaping engine", meaning unique scripts will be broken up into |
| // separate items. |
| bool lastResortFontTried = false; |
| while (fontData) { |
| // The recommended size for the glyph buffer is 1.5 * the character length + 16 in the uniscribe docs. |
| // Apparently this is a good size to avoid having to make repeated calls to ScriptShape. |
| glyphs.resize(1.5 * len + 16); |
| visualAttributes.resize(glyphs.size()); |
| |
| if (shape(str, len, item, fontData, glyphs, clusters, visualAttributes)) |
| break; |
| |
| // Try again with the next font in the list. |
| if (lastResortFontTried) { |
| fontData = 0; |
| break; |
| } |
| |
| fontData = m_font.fontDataAt(++dataIndex); |
| if (!fontData) { |
| // Out of fonts. Get a font data based on the actual characters. |
| fontData = m_font.fontDataForCharacters(str, len); |
| lastResortFontTried = true; |
| } |
| if (smallCaps) |
| fontData = fontData->smallCapsFontData(m_font.fontDescription()); |
| } |
| |
| // Just give up. We were unable to shape. |
| if (!fontData) |
| return true; |
| |
| // We now have a collection of glyphs. |
| Vector<GOFFSET> offsets; |
| Vector<int> advances; |
| offsets.resize(glyphs.size()); |
| advances.resize(glyphs.size()); |
| int glyphCount = 0; |
| HRESULT placeResult = ScriptPlace(0, fontData->scriptCache(), glyphs.data(), glyphs.size(), visualAttributes.data(), |
| &item.a, advances.data(), offsets.data(), 0); |
| if (placeResult == E_PENDING) { |
| // The script cache isn't primed with enough info yet. We need to select our HFONT into |
| // a DC and pass the DC in to ScriptPlace. |
| HDC hdc = GetDC(0); |
| HFONT hfont = fontData->platformData().hfont(); |
| HFONT oldFont = (HFONT)SelectObject(hdc, hfont); |
| placeResult = ScriptPlace(hdc, fontData->scriptCache(), glyphs.data(), glyphs.size(), visualAttributes.data(), |
| &item.a, advances.data(), offsets.data(), 0); |
| SelectObject(hdc, oldFont); |
| ReleaseDC(0, hdc); |
| } |
| |
| if (FAILED(placeResult) || glyphs.isEmpty()) |
| return true; |
| |
| // Convert all chars that should be treated as spaces to use the space glyph. |
| // We also create a map that allows us to quickly go from space glyphs or rounding |
| // hack glyphs back to their corresponding characters. |
| Vector<int> spaceCharacters(glyphs.size()); |
| spaceCharacters.fill(-1); |
| Vector<int> roundingHackCharacters(glyphs.size()); |
| roundingHackCharacters.fill(-1); |
| Vector<int> roundingHackWordBoundaries(glyphs.size()); |
| roundingHackWordBoundaries.fill(-1); |
| unsigned logicalSpaceWidth = fontData->m_spaceWidth * 32.0f; |
| float roundedSpaceWidth = roundf(fontData->m_spaceWidth); |
| |
| for (int k = 0; k < len; k++) { |
| UChar ch = *(str + k); |
| if (Font::treatAsSpace(ch)) { |
| // Substitute in the space glyph at the appropriate place in the glyphs |
| // array. |
| glyphs[clusters[k]] = fontData->m_spaceGlyph; |
| advances[clusters[k]] = logicalSpaceWidth; |
| spaceCharacters[clusters[k]] = m_currentCharacter + k + m_items[i].iCharPos; |
| } |
| |
| if (Font::isRoundingHackCharacter(ch)) |
| roundingHackCharacters[clusters[k]] = m_currentCharacter + k + m_items[i].iCharPos; |
| |
| int boundary = k + m_currentCharacter + m_items[i].iCharPos; |
| if (boundary < m_run.length() && |
| Font::isRoundingHackCharacter(*(str + k + 1))) |
| roundingHackWordBoundaries[clusters[k]] = boundary; |
| } |
| |
| // Populate our glyph buffer with this information. |
| bool hasExtraSpacing = m_font.letterSpacing() || m_font.wordSpacing() || m_padding; |
| |
| float leftEdge = m_runWidthSoFar; |
| |
| for (unsigned k = 0; k < glyphs.size(); k++) { |
| Glyph glyph = glyphs[k]; |
| float advance = advances[k] / 32.0f; |
| float offsetX = offsets[k].du / 32.0f; |
| float offsetY = offsets[k].dv / 32.0f; |
| |
| // Match AppKit's rules for the integer vs. non-integer rendering modes. |
| float roundedAdvance = roundf(advance); |
| if (!m_font.isPrinterFont() && !fontData->isSystemFont()) { |
| advance = roundedAdvance; |
| offsetX = roundf(offsetX); |
| offsetY = roundf(offsetY); |
| } |
| |
| // We special case spaces in two ways when applying word rounding. |
| // First, we round spaces to an adjusted width in all fonts. |
| // Second, in fixed-pitch fonts we ensure that all glyphs that |
| // match the width of the space glyph have the same width as the space glyph. |
| if (roundedAdvance == roundedSpaceWidth && (fontData->m_treatAsFixedPitch || glyph == fontData->m_spaceGlyph) && |
| m_style.applyWordRounding()) |
| advance = fontData->m_adjustedSpaceWidth; |
| |
| if (hasExtraSpacing) { |
| // If we're a glyph with an advance, go ahead and add in letter-spacing. |
| // That way we weed out zero width lurkers. This behavior matches the fast text code path. |
| if (advance && m_font.letterSpacing()) |
| advance += m_font.letterSpacing(); |
| |
| // Handle justification and word-spacing. |
| if (glyph == fontData->m_spaceGlyph) { |
| // Account for padding. WebCore uses space padding to justify text. |
| // We distribute the specified padding over the available spaces in the run. |
| if (m_padding) { |
| // Use leftover padding if not evenly divisible by number of spaces. |
| if (m_padding < m_padPerSpace) { |
| advance += m_padding; |
| m_padding = 0; |
| } else { |
| advance += m_padPerSpace; |
| m_padding -= m_padPerSpace; |
| } |
| } |
| |
| // Account for word-spacing. |
| int characterIndex = spaceCharacters[k]; |
| if (characterIndex > 0 && !Font::treatAsSpace(*m_run.data(characterIndex-1)) && m_font.wordSpacing()) |
| advance += m_font.wordSpacing(); |
| } |
| } |
| |
| // Deal with the float/integer impedance mismatch between CG and WebCore. "Words" (characters |
| // followed by a character defined by isRoundingHackCharacter()) are always an integer width. |
| // We adjust the width of the last character of a "word" to ensure an integer width. |
| // Force characters that are used to determine word boundaries for the rounding hack |
| // to be integer width, so the following words will start on an integer boundary. |
| int roundingHackIndex = roundingHackCharacters[k]; |
| if (m_style.applyWordRounding() && roundingHackIndex != -1) |
| advance = ceilf(advance); |
| |
| // Check to see if the next character is a "rounding hack character", if so, adjust the |
| // width so that the total run width will be on an integer boundary. |
| int position = m_currentCharacter + len; |
| bool lastGlyph = (k == glyphs.size() - 1) && (m_style.rtl() ? i == 0 : i == m_items.size() - 2) && (position >= m_end); |
| if ((m_style.applyWordRounding() && roundingHackWordBoundaries[k] != -1) || |
| (m_style.applyRunRounding() && lastGlyph)) { |
| float totalWidth = m_runWidthSoFar + advance; |
| advance += ceilf(totalWidth) - totalWidth; |
| } |
| |
| m_runWidthSoFar += advance; |
| |
| // FIXME: We need to take the GOFFSETS for combining glyphs and store them in the glyph buffer |
| // as well, so that when the time comes to draw those glyphs, we can apply the appropriate |
| // translation. |
| if (glyphBuffer) { |
| FloatSize size(offsetX, offsetY); |
| glyphBuffer->add(glyph, fontData, advance, &size); |
| } |
| |
| // Mutate the glyph array to contain our altered advances. |
| if (m_computingOffsetPosition) |
| advances[k] = advance; |
| } |
| |
| while (m_computingOffsetPosition && m_offsetX >= leftEdge && m_offsetX < m_runWidthSoFar) { |
| // The position is somewhere inside this run. |
| int trailing = 0; |
| ScriptXtoCP(m_offsetX - leftEdge, clusters.size(), glyphs.size(), clusters.data(), visualAttributes.data(), |
| advances.data(), &item.a, &m_offsetPosition, &trailing); |
| if (trailing && m_includePartialGlyphs && m_offsetPosition < len - 1) { |
| m_offsetPosition += m_currentCharacter + m_items[i].iCharPos; |
| m_offsetX += m_style.rtl() ? -trailing : trailing; |
| } else { |
| m_computingOffsetPosition = false; |
| m_offsetPosition += m_currentCharacter + m_items[i].iCharPos; |
| if (trailing && m_includePartialGlyphs) |
| m_offsetPosition++; |
| return false; |
| } |
| } |
| |
| return true; |
| } |
| |
| bool UniscribeController::shape(const UChar* str, int len, SCRIPT_ITEM item, const FontData* fontData, |
| Vector<WORD>& glyphs, Vector<WORD>& clusters, |
| Vector<SCRIPT_VISATTR>& visualAttributes) |
| { |
| HDC hdc = 0; |
| HFONT oldFont = 0; |
| HRESULT shapeResult = E_PENDING; |
| int glyphCount = 0; |
| do { |
| shapeResult = ScriptShape(hdc, fontData->scriptCache(), str, len, glyphs.size(), &item.a, |
| glyphs.data(), clusters.data(), visualAttributes.data(), &glyphCount); |
| if (shapeResult == E_PENDING) { |
| // The script cache isn't primed with enough info yet. We need to select our HFONT into |
| // a DC and pass the DC in to ScriptShape. |
| ASSERT(!hdc); |
| hdc = GetDC(0); |
| HFONT hfont = fontData->platformData().hfont(); |
| oldFont = (HFONT)SelectObject(hdc, hfont); |
| } else if (shapeResult == E_OUTOFMEMORY) { |
| // Need to resize our buffers. |
| glyphs.resize(glyphs.size() * 2); |
| visualAttributes.resize(glyphs.size()); |
| } |
| } while (shapeResult == E_PENDING || shapeResult == E_OUTOFMEMORY); |
| |
| if (hdc) { |
| SelectObject(hdc, oldFont); |
| ReleaseDC(0, hdc); |
| } |
| |
| if (FAILED(shapeResult)) |
| return false; |
| |
| // FIXME: We need to do better than this. Falling back on the entire item is not good enough. |
| // We may still have missing glyphs even if we succeeded. We need to treat missing glyphs as |
| // a failure so that we will fall back to another font. |
| bool containsMissingGlyphs = false; |
| SCRIPT_FONTPROPERTIES* fontProperties = fontData->scriptFontProperties(); |
| for (int i = 0; i < glyphCount; i++) { |
| WORD glyph = glyphs[i]; |
| if (glyph == fontProperties->wgDefault) { |
| containsMissingGlyphs = true; |
| break; |
| } |
| } |
| |
| if (containsMissingGlyphs) |
| return false; |
| |
| glyphs.resize(glyphCount); |
| visualAttributes.resize(glyphCount); |
| |
| return true; |
| } |
| |
| } |
