/* | |
* 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 "SimpleFontData.h" | |
#include <wtf/MathExtras.h> | |
using namespace std; | |
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, HashSet<const SimpleFontData*>* fallbackFonts) | |
: m_font(*font) | |
, m_run(run) | |
, m_fallbackFonts(fallbackFonts) | |
, m_minGlyphBoundingBoxX(numeric_limits<float>::max()) | |
, m_maxGlyphBoundingBoxX(numeric_limits<float>::min()) | |
, m_minGlyphBoundingBoxY(numeric_limits<float>::max()) | |
, m_maxGlyphBoundingBoxY(numeric_limits<float>::min()) | |
, 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_run.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_run.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_run.ltr() || m_offsetX < 0 && m_run.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; | |
unsigned baseCharacter = m_currentCharacter; | |
// We break up itemization of the string by fontData and (if needed) the use of small caps. | |
// FIXME: It's inconsistent that we use logical order when itemizing, since this | |
// does not match normal RTL. | |
// FIXME: This function should decode surrogate pairs. Currently it makes little difference that | |
// it does not because the font cache on Windows does not support non-BMP characters. | |
Vector<UChar, 256> smallCapsBuffer; | |
if (m_font.isSmallCaps()) | |
smallCapsBuffer.resize(length); | |
unsigned indexOfFontTransition = m_run.rtl() ? length - 1 : 0; | |
const UChar* curr = m_run.rtl() ? cp + length - 1 : cp; | |
const UChar* end = m_run.rtl() ? cp - 1 : cp + length; | |
const SimpleFontData* fontData; | |
const SimpleFontData* nextFontData = m_font.glyphDataForCharacter(*curr, false).fontData; | |
UChar newC = 0; | |
bool isSmallCaps; | |
bool nextIsSmallCaps = m_font.isSmallCaps() && !(U_GET_GC_MASK(*curr) & U_GC_M_MASK) && (newC = u_toupper(*curr)) != *curr; | |
if (nextIsSmallCaps) | |
smallCapsBuffer[curr - cp] = newC; | |
while (true) { | |
curr = m_run.rtl() ? curr - 1 : curr + 1; | |
if (curr == end) | |
break; | |
fontData = nextFontData; | |
isSmallCaps = nextIsSmallCaps; | |
int index = curr - cp; | |
UChar c = *curr; | |
bool forceSmallCaps = isSmallCaps && (U_GET_GC_MASK(c) & U_GC_M_MASK); | |
nextFontData = m_font.glyphDataForCharacter(*curr, false, forceSmallCaps).fontData; | |
if (m_font.isSmallCaps()) { | |
nextIsSmallCaps = forceSmallCaps || (newC = u_toupper(c)) != c; | |
if (nextIsSmallCaps) | |
smallCapsBuffer[index] = forceSmallCaps ? c : newC; | |
} | |
if (m_fallbackFonts && nextFontData != fontData && fontData != m_font.primaryFont()) | |
m_fallbackFonts->add(fontData); | |
if (nextFontData != fontData || nextIsSmallCaps != isSmallCaps) { | |
int itemStart = m_run.rtl() ? index + 1 : indexOfFontTransition; | |
int itemLength = m_run.rtl() ? indexOfFontTransition - index : index - indexOfFontTransition; | |
m_currentCharacter = baseCharacter + itemStart; | |
itemizeShapeAndPlace((isSmallCaps ? smallCapsBuffer.data() : cp) + itemStart, itemLength, fontData, glyphBuffer); | |
indexOfFontTransition = index; | |
} | |
} | |
int itemLength = m_run.rtl() ? indexOfFontTransition + 1 : length - indexOfFontTransition; | |
if (itemLength) { | |
if (m_fallbackFonts && nextFontData != m_font.primaryFont()) | |
m_fallbackFonts->add(nextFontData); | |
int itemStart = m_run.rtl() ? 0 : indexOfFontTransition; | |
m_currentCharacter = baseCharacter + itemStart; | |
itemizeShapeAndPlace((nextIsSmallCaps ? smallCapsBuffer.data() : cp) + itemStart, itemLength, nextFontData, glyphBuffer); | |
} | |
m_currentCharacter = baseCharacter + length; | |
} | |
void UniscribeController::itemizeShapeAndPlace(const UChar* cp, unsigned length, const SimpleFontData* fontData, 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_run.rtl()) { | |
for (int i = m_items.size() - 2; i >= 0; i--) { | |
if (!shapeAndPlaceItem(cp, i, fontData, glyphBuffer)) | |
return; | |
} | |
} else { | |
for (unsigned i = 0; i < m_items.size() - 1; i++) { | |
if (!shapeAndPlaceItem(cp, i, fontData, glyphBuffer)) | |
return; | |
} | |
} | |
} | |
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_run.rtl(); | |
// Lock the correct directional override. | |
m_state.fOverrideDirection = m_run.directionalOverride(); | |
} | |
bool UniscribeController::shapeAndPlaceItem(const UChar* cp, unsigned i, const SimpleFontData* fontData, 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]; | |
// 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. | |
// 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)) | |
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); | |
const float cLogicalScale = fontData->platformData().useGDI() ? 1.0f : 32.0f; | |
unsigned logicalSpaceWidth = fontData->spaceWidth() * cLogicalScale; | |
float roundedSpaceWidth = roundf(fontData->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->spaceGlyph(); | |
advances[clusters[k]] = logicalSpaceWidth; | |
spaceCharacters[clusters[k]] = m_currentCharacter + k + item.iCharPos; | |
} | |
if (Font::isRoundingHackCharacter(ch)) | |
roundingHackCharacters[clusters[k]] = m_currentCharacter + k + item.iCharPos; | |
int boundary = k + m_currentCharacter + item.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] / cLogicalScale; | |
float offsetX = offsets[k].du / cLogicalScale; | |
float offsetY = offsets[k].dv / cLogicalScale; | |
// 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); | |
} | |
advance += fontData->syntheticBoldOffset(); | |
// 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->pitch() == FixedPitch || glyph == fontData->spaceGlyph()) && | |
m_run.applyWordRounding()) | |
advance = fontData->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->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_run.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_run.rtl() ? i == 0 : i == m_items.size() - 2) && (position >= m_end); | |
if ((m_run.applyWordRounding() && roundingHackWordBoundaries[k] != -1) || | |
(m_run.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); | |
} | |
GlyphMetrics glyphMetrics = fontData->metricsForGlyph(glyph); | |
glyphMetrics.boundingBox.move(m_glyphOrigin.x(), m_glyphOrigin.y()); | |
m_minGlyphBoundingBoxX = min(m_minGlyphBoundingBoxX, glyphMetrics.boundingBox.x()); | |
m_maxGlyphBoundingBoxX = max(m_maxGlyphBoundingBoxX, glyphMetrics.boundingBox.right()); | |
m_minGlyphBoundingBoxY = min(m_minGlyphBoundingBoxY, glyphMetrics.boundingBox.y()); | |
m_maxGlyphBoundingBoxY = max(m_maxGlyphBoundingBoxY, glyphMetrics.boundingBox.bottom()); | |
m_glyphOrigin.move(advance + offsetX, -offsetY); | |
// 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_run.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 SimpleFontData* 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; | |
glyphs.shrink(glyphCount); | |
visualAttributes.shrink(glyphCount); | |
return true; | |
} | |
} |