private CharacterPositionInfo GetCharacterAtPoint(Point pt)
{
CharacterPositionInfo ret = new CharacterPositionInfo();
//find line
int line_index = GetLineIndexFromPoint(pt);
//если pt не соответсвует ни одной линии...
if (line_index == -1)
{
ret.CharIndex = -1;
ret.OffsetToNextCaretPosition = 0;
ret.PositionType = CharacterPositionType.AfterEnd;
ret.Xoffset = pt.X;
return(ret);
}
//если линия найдена...
ret = lines_info[line_index].GetCharacterIndexAtX(pt.X - Bounds.X);
//поправляем, чтобы ret.CharIndex был бы относительно экрана
ret.CharIndex = ret.CharIndex + lines_info[line_index].CharFirst;
return(ret);
}
public CharacterPositionInfo GetCharacterIndexAtX(int xOffset)
{
return(CharacterPositionInfo.FromXoffset(ssa_struct_ptr, xOffset));
}
public HitTextResult HitTest(Point pt)
{
HitTextResult ret = new HitTextResult();
if (LinesCount == 0)
{
ret.CharacterIndex = -1;
ret.CharacterIndexInLine = -1;
ret.LineIndex = -1;
ret.HitTextType = HitTextType.BeforeText;
return(ret);
}
if (pt.Y < lines_info[0].ReferensePoint.Y)
{
ret.CharacterIndex = -1;
ret.CharacterIndexInLine = -1;
ret.LineIndex = -1;
ret.HitTextType = HitTextType.BeforeText;
return(ret);
}
if (pt.Y > lines_info[LinesCount - 1].ReferensePoint.Y + lines_info[LinesCount - 1].Extent.Height)
{
ret.CharacterIndex = -1;
ret.CharacterIndexInLine = -1;
ret.LineIndex = -1;
ret.HitTextType = HitTextType.AfterText;
return(ret);
}
int line_index = GetLineIndexFromPoint(pt);
if (line_index == -1)
{
ret.CharacterIndex = -1;
ret.CharacterIndexInLine = -1;
ret.LineIndex = -1;
ret.HitTextType = HitTextType.Undefined;
return(ret);
}
CharacterPositionInfo cpi = lines_info[line_index].GetCharacterIndexAtX(pt.X - lines_info[line_index].ReferensePoint.X);
ret.CharacterIndex = cpi.CharIndex + lines_info[line_index].CharFirst;
ret.CharacterIndexInLine = cpi.CharIndex;
ret.LineIndex = line_index;
switch (cpi.PositionType)
{
case CharacterPositionType.LeadingEdge:
case CharacterPositionType.TrailingEdge:
case CharacterPositionType.ClusterPart:
ret.HitTextType = HitTextType.Glyph;
break;
case CharacterPositionType.BeforeBeginning:
ret.HitTextType = HitTextType.BeforeOfLine;
break;
case CharacterPositionType.AfterEnd:
ret.HitTextType = HitTextType.AfterOfLine;
break;
}
return(ret);
}
public Point GetCaretPosition(int char_index, out bool outside)
{
Point ret = new Point();
//найдем линию
int line_index = GetLineIndexFromCharacterIndex(char_index);
if (line_index == -1)
{
outside = true;
return(ret);
}
//позиция внутри линии
int char_index_in_line = char_index - lines_info[line_index].CharFirst;
//а что если запрашивается позиция в коце текста?
//тогда придется вернуть trailing edge предыдущего символа
//при этом если предыдущий символ \n, то каретку надо бы поставить на следующую строку
//и проверить не вылазиет ли она за пределы экрана;
//а если предыдущего нет, то есть текст пуст вернем вехний левый угол
bool is_trailing_edge = false;
if (char_index_in_line >= lines_info[line_index].CharLength)
{
if (char_index_in_line > 0)
{
char_index_in_line = char_index_in_line - 1;
is_trailing_edge = true;
char pre_char = GetChar(lines_info[line_index].CharFirst + char_index_in_line);
if (pre_char == '\n')
{
ret = lines_info[line_index].ReferensePoint;
ret.Y = ret.Y + lines_info[line_index].Extent.Height;
outside = (ret.Y > Bounds.Bottom);
return(ret);
}
}
else
{
ret = lines_info[line_index].ReferensePoint;
outside = false;
return(ret);
}
}
CharacterPositionInfo char_info = lines_info[line_index].GetX_AtCharacterIndex
(char_index_in_line, is_trailing_edge);
ret = new Point(char_info.Xoffset + Bounds.X, lines_info[line_index].ReferensePoint.Y);
//System.Windows.Forms.MessageBox.Show
// (ret.ToString() +
// " line #" + line_index.ToString() +
// "; char #" + char_index_in_line.ToString() +
// "; line first char #" + lines_info[line_index].CharFirst.ToString() +
// "; line char length " + lines_info[line_index].CharLength.ToString() +
// "; char: " + char.ToString(GetChar(char_index)));
outside = false;
return(ret);
}