using a shared buffer for QTextBoundaryFinder

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

diff --git a/src/qtui/chatlinemodelitem.cpp b/src/qtui/chatlinemodelitem.cpp
index 009d535..9b9e71c 100644 (file)
--- a/src/qtui/chatlinemodelitem.cpp
+++ b/src/qtui/chatlinemodelitem.cpp
@@ -18,12 +18,31 @@
  *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
  ***************************************************************************/
 
+#include <QFontMetrics>
+#include <QTextBoundaryFinder>
+
 #include "chatlinemodelitem.h"
 #include "chatlinemodel.h"
 #include "qtui.h"
 #include "uistyle.h"
 
-ChatlineModelItem::ChatlineModelItem(const Message &msg) : MessageModelItem(msg) {
+// This Struct is taken from Harfbuzz. We use it only to calc it's size.
+// we use a shared memory region so we do not have to malloc a buffer area for every line
+typedef struct {
+    /*HB_LineBreakType*/ unsigned lineBreakType  :2;
+    /*HB_Bool*/ unsigned whiteSpace              :1;     /* A unicode whitespace character, except NBSP, ZWNBSP */
+    /*HB_Bool*/ unsigned charStop                :1;     /* Valid cursor position (for left/right arrow) */
+    /*HB_Bool*/ unsigned wordBoundary            :1;
+    /*HB_Bool*/ unsigned sentenceBoundary        :1;
+    unsigned unused                  :2;
+} HB_CharAttributes_Dummy;
+
+unsigned char *ChatLineModelItem::TextBoundaryFinderBuffer = (unsigned char *)malloc(512 * sizeof(HB_CharAttributes_Dummy));
+int ChatLineModelItem::TextBoundaryFinderBufferSize = 512 * (sizeof(HB_CharAttributes_Dummy) / sizeof(unsigned char));
+
+ChatLineModelItem::ChatLineModelItem(const Message &msg)
+  : MessageModelItem(msg)
+{
   QtUiStyle::StyledMessage m = QtUi::style()->styleMessage(msg);
 
   _timestamp.plainText = m.timestamp.plainText;
@@ -34,27 +53,109 @@ ChatlineModelItem::ChatlineModelItem(const Message &msg) : MessageModelItem(msg)
   _sender.formatList = m.sender.formatList;
   _contents.formatList = m.contents.formatList;
 
+  computeWrapList();
 }
 
 
-QVariant ChatlineModelItem::data(int column, int role) const {
-  const ChatlinePart *part;
+QVariant ChatLineModelItem::data(int column, int role) const {
+  const ChatLinePart *part = 0;
 
   switch(column) {
-    case ChatlineModel::TimestampColumn: part = &_timestamp; break;
-    case ChatlineModel::SenderColumn:    part = &_sender; break;
-    case ChatlineModel::TextColumn:      part = &_contents; break;
-    default: return MessageModelItem::data(column, role);
+  case ChatLineModel::TimestampColumn:
+    part = &_timestamp;
+    break;
+  case ChatLineModel::SenderColumn:
+    part = &_sender;
+    break;
+  case ChatLineModel::ContentsColumn:
+    part = &_contents;
+    break;
+  default:
+    return MessageModelItem::data(column, role);
   }
 
   switch(role) {
-    case ChatlineModel::DisplayRole: return part->plainText;
-    case ChatlineModel::FormatRole:  return QVariant::fromValue<UiStyle::FormatList>(part->formatList);
+  case ChatLineModel::DisplayRole:
+    return part->plainText;
+  case ChatLineModel::FormatRole:
+    return QVariant::fromValue<UiStyle::FormatList>(part->formatList);
+  case ChatLineModel::WrapListRole:
+    if(column != ChatLineModel::ContentsColumn)
+      return QVariant();
+    return QVariant::fromValue<ChatLineModel::WrapList>(_wrapList);
   }
-
   return MessageModelItem::data(column, role);
 }
 
-bool ChatlineModelItem::setData(int column, const QVariant &value, int role) {
-  return false;
+void ChatLineModelItem::computeWrapList() {
+  if(_contents.plainText.isEmpty())
+    return;
+
+  enum Mode { SearchStart, SearchEnd };
+
+  QList<ChatLineModel::Word> wplist;  // use a temp list which we'll later copy into a QVector for efficiency
+  // QTextBoundaryFinder finder(QTextBoundaryFinder::Word, _contents.plainText);
+  QTextBoundaryFinder finder(QTextBoundaryFinder::Word, _contents.plainText.unicode(), _contents.plainText.length(), TextBoundaryFinderBuffer, TextBoundaryFinderBufferSize);
+
+  int idx;
+  int oldidx = 0;
+  bool wordStart = false;
+  bool wordEnd = false;
+  Mode mode = SearchEnd;
+  ChatLineModel::Word word;
+  word.start = 0;
+  int wordstartx = 0;
+
+  QTextLayout layout(_contents.plainText);
+  QTextOption option;
+  option.setWrapMode(QTextOption::NoWrap);
+  layout.setTextOption(option);
+
+  layout.setAdditionalFormats(QtUi::style()->toTextLayoutList(_contents.formatList, _contents.plainText.length()));
+  layout.beginLayout();
+  QTextLine line = layout.createLine();
+  line.setNumColumns(_contents.plainText.length());
+  layout.endLayout();
+
+  do {
+    idx = finder.toNextBoundary();
+    if(idx < 0) {
+      idx = _contents.plainText.length();
+      wordStart = false;
+      wordEnd = false;
+      mode = SearchStart;
+    } else {
+      wordStart = finder.boundaryReasons().testFlag(QTextBoundaryFinder::StartWord);
+      wordEnd = finder.boundaryReasons().testFlag(QTextBoundaryFinder::EndWord);
+    }
+
+    //if(flg) qDebug() << idx << mode << wordStart << wordEnd << _contents.plainText.left(idx) << _contents.plainText.mid(idx);
+
+    if(mode == SearchEnd || (!wordStart && wordEnd)) {
+      if(wordStart || !wordEnd) continue;
+      oldidx = idx;
+      mode = SearchStart;
+      continue;
+    }
+    int wordendx = line.cursorToX(oldidx);
+    int trailingendx = line.cursorToX(idx);
+    word.width = wordendx - wordstartx;
+    word.trailing = trailingendx - wordendx;
+    wordstartx = trailingendx;
+    wplist.append(word);
+
+    if(wordStart) {
+      word.start = idx;
+      mode = SearchEnd;
+    }
+    // the part " || (finder.position() == _contents.plainText.length())" shouldn't be necessary
+    // but in rare and indeterministic cases Qt states that the end of the text is not a boundary o_O
+  } while(finder.isAtBoundary() || (finder.position() == _contents.plainText.length()));
+
+  // A QVector needs less space than a QList
+  _wrapList.resize(wplist.count());
+  for(int i = 0; i < wplist.count(); i++) {
+    _wrapList[i] = wplist.at(i);
+  }
 }
+