int ComplexTextController::offsetForPosition(int targetX)
{
unsigned basePosition = 0;
int x = offsetX();
while (nextScriptRun()) {
int nextX = offsetX();
if (std::min(x, nextX) <= targetX && targetX <= std::max(x, nextX)) {
// The x value in question is within this script run.
const int glyphIndex = glyphIndexForXPositionInScriptRun(targetX);
// Now that we have a glyph index, we have to turn that into a
// code-point index. Because of ligatures, several code-points may
// have gone into a single glyph. We iterate over the clusters log
// and find the first code-point which contributed to the glyph.
// Some shapers (i.e. Khmer) will produce cluster logs which report
// that /no/ code points contributed to certain glyphs. Because of
// this, we take any code point which contributed to the glyph in
// question, or any subsequent glyph. If we run off the end, then
// we take the last code point.
for (unsigned j = 0; j < numCodePoints(); ++j) {
if (m_item.log_clusters[j] >= glyphIndex)
return basePosition + j;
}
return basePosition + numCodePoints() - 1;
}
basePosition += numCodePoints();
}
return basePosition;
}
float ComplexTextController::widthOfFullRun()
{
float widthSum = 0;
while (nextScriptRun())
widthSum += width();
return widthSum;
}
float widthOfFullRun()
{
float widthSum = 0;
while (nextScriptRun())
widthSum += width();
return widthSum;
}
FloatRect ComplexTextController::selectionRect(const FloatPoint& point, int height, int from, int to)
{
int fromX = -1, toX = -1;
// Iterate through the script runs in logical order, searching for the run covering the positions of interest.
while (nextScriptRun() && (fromX == -1 || toX == -1)) {
if (fromX == -1 && from >= 0 && static_cast<unsigned>(from) < numCodePoints()) {
// |from| is within this script run. So we index the clusters log to
// find which glyph this code-point contributed to and find its x
// position.
int glyph = m_item.log_clusters[from];
fromX = positions()[glyph].x();
if (rtl())
fromX += truncateFixedPointToInteger(m_item.advances[glyph]);
} else
from -= numCodePoints();
if (toX == -1 && to >= 0 && static_cast<unsigned>(to) < numCodePoints()) {
int glyph = m_item.log_clusters[to];
toX = positions()[glyph].x();
if (rtl())
toX += truncateFixedPointToInteger(m_item.advances[glyph]);
} else
to -= numCodePoints();
}
// The position in question might be just after the text.
if (fromX == -1)
fromX = offsetX();
if (toX == -1)
toX = offsetX();
ASSERT(fromX != -1 && toX != -1);
if (fromX < toX)
return FloatRect(point.x() + fromX, point.y(), toX - fromX, height);
return FloatRect(point.x() + toX, point.y(), fromX - toX, height);
}
