Revert "Remove the word boundary cache"

[quassel.git] / src / qtui / chatitem.cpp

diff --git a/src/qtui/chatitem.cpp b/src/qtui/chatitem.cpp
index 819877a..390e428 100644 (file)
--- a/src/qtui/chatitem.cpp
+++ b/src/qtui/chatitem.cpp
@@ -89,15 +89,11 @@ void ChatItem::initLayoutHelper(QTextLayout *layout, QTextOption::WrapMode wrapM
 }
 
 void ChatItem::doLayout(QTextLayout *layout) const {
-  qreal h = 0;
   layout->beginLayout();
-  forever {
-    QTextLine line = layout->createLine();
-    if(!line.isValid())
-      break;
+  QTextLine line = layout->createLine();
+  if(line.isValid()) {
     line.setLineWidth(width());
-    line.setPosition(QPointF(0, h));
-    h += line.height();
+    line.setPosition(QPointF(0,0));
   }
   layout->endLayout();
 }
@@ -398,15 +394,38 @@ qreal ContentsChatItem::setGeometryByWidth(qreal w) {
   //if(w != width()) {
     prepareGeometryChange();
     setWidth(w);
-    QTextLayout layout;
-    initLayout(&layout);
-    setHeight(layout.boundingRect().height());
+    // compute height
+    int lines = 1;
+    WrapColumnFinder finder(this);
+    while(finder.nextWrapColumn() > 0)
+      lines++;
+    setHeight(lines * fontMetrics()->lineSpacing());
     delete _data;
     _data = 0;
   //}
   return height();
 }
 
+void ContentsChatItem::doLayout(QTextLayout *layout) const {
+  ChatLineModel::WrapList wrapList = data(ChatLineModel::WrapListRole).value<ChatLineModel::WrapList>();
+  if(!wrapList.count()) return; // empty chatitem
+
+  qreal h = 0;
+  WrapColumnFinder finder(this);
+  layout->beginLayout();
+  forever {
+    QTextLine line = layout->createLine();
+    if(!line.isValid())
+      break;
+
+    int col = finder.nextWrapColumn();
+    line.setNumColumns(col >= 0 ? col - line.textStart() : layout->text().length());
+    line.setPosition(QPointF(0, h));
+    h += fontMetrics()->lineSpacing();
+  }
+  layout->endLayout();
+}
+
 // NOTE: This method is not threadsafe and not reentrant!
 //       (RegExps are not constant while matching, and they are static here for efficiency)
 QList<ContentsChatItem::Clickable> ContentsChatItem::findClickables() const {
@@ -669,3 +688,66 @@ void ContentsChatItem::clearWebPreview() {
 
 /*************************************************************************************************/
 
+ContentsChatItem::WrapColumnFinder::WrapColumnFinder(const ChatItem *_item)
+  : item(_item),
+    wrapList(item->data(ChatLineModel::WrapListRole).value<ChatLineModel::WrapList>()),
+    wordidx(0),
+    lineCount(0),
+    choppedTrailing(0)
+{
+}
+
+ContentsChatItem::WrapColumnFinder::~WrapColumnFinder() {
+}
+
+qint16 ContentsChatItem::WrapColumnFinder::nextWrapColumn() {
+  if(wordidx >= wrapList.count())
+    return -1;
+
+  lineCount++;
+  qreal targetWidth = lineCount * item->width() + choppedTrailing;
+
+  qint16 start = wordidx;
+  qint16 end = wrapList.count() - 1;
+
+  // check if the whole line fits
+  if(wrapList.at(end).endX <= targetWidth) //  || start == end)
+    return -1;
+
+  // check if we have a very long word that needs inter word wrap
+  if(wrapList.at(start).endX > targetWidth) {
+    if(!line.isValid()) {
+      item->initLayoutHelper(&layout, QTextOption::NoWrap);
+      layout.beginLayout();
+      line = layout.createLine();
+      layout.endLayout();
+    }
+    return line.xToCursor(targetWidth, QTextLine::CursorOnCharacter);
+  }
+
+  while(true) {
+    if(start + 1 == end) {
+      wordidx = end;
+      const ChatLineModel::Word &lastWord = wrapList.at(start); // the last word we were able to squeeze in
+
+      // both cases should be cought preliminary
+      Q_ASSERT(lastWord.endX <= targetWidth); // ensure that "start" really fits in
+      Q_ASSERT(end < wrapList.count()); // ensure that start isn't the last word
+
+      choppedTrailing += lastWord.trailing - (targetWidth - lastWord.endX);
+      return wrapList.at(wordidx).start;
+    }
+
+    qint16 pivot = (end + start) / 2;
+    if(wrapList.at(pivot).endX > targetWidth) {
+      end = pivot;
+    } else {
+      start = pivot;
+    }
+  }
+  Q_ASSERT(false);
+  return -1;
+}
+
+/*************************************************************************************************/
+