public static CharacterPositionInfo FromCharIndex(IntPtr ssa_struct, int char_index, CharacterPositionType pos_type)
{
if ((pos_type == CharacterPositionType.AfterEnd) ||
(pos_type == CharacterPositionType.BeforeBeginning) ||
(pos_type == CharacterPositionType.ClusterPart))
{
throw new ArgumentException("Illegal parameter.", "pos_type");
}
var trailing = (pos_type == CharacterPositionType.TrailingEdge);
var x_offset = 0;
var res = NativeScript.ScriptStringCPtoX
(ssa_struct,
char_index,
trailing,
ref x_offset);
if (res != NativeScript.S_OK)
{
Marshal.ThrowExceptionForHR(res);
}
var ret = new CharacterPositionInfo();
ret.CharIndex = char_index;
ret.PositionType = pos_type;
ret.Xoffset = x_offset;
return(ret);
}
public static CharacterPositionInfo FromXoffset(IntPtr ssa_struct, int x_offset)
{
var char_pos = 0;
var char_trailing = 0;
if (ssa_struct == IntPtr.Zero)
{
x_offset = 0;
return(new CharacterPositionInfo());
}
var res = NativeScript.ScriptStringXtoCP
(ssa_struct,
x_offset,
ref char_pos,
ref char_trailing);
if (res != NativeScript.S_OK)
{
Marshal.ThrowExceptionForHR(res);
}
var chars_count = NativeScript.GetPcOutChars(ssa_struct);
var ret = new CharacterPositionInfo();
ret.CharIndex = char_pos;
ret.Xoffset = x_offset;
if (char_trailing == 0)
{
if (char_pos == chars_count)
{
ret.PositionType = CharacterPositionType.AfterEnd;
}
else
{
ret.PositionType = CharacterPositionType.LeadingEdge;
}
}
else if (char_trailing == 1)
{
if (char_pos == -1)
{
ret.PositionType = CharacterPositionType.BeforeBeginning;
}
else
{
ret.PositionType = CharacterPositionType.TrailingEdge;
}
}
else
{
ret.PositionType = CharacterPositionType.ClusterPart;
ret.OffsetToNextCaretPosition = char_trailing;
}
return(ret);
}
/// <summary>
/// dispose obligatory!!
/// </summary>
public void Dispose()
{
if (ssa_struct_ptr != IntPtr.Zero)
{
int res = NativeScript.ScriptStringFree(ref ssa_struct_ptr);
if (res != 0)
{
Marshal.ThrowExceptionForHR(res);
}
}
}
public void Render(int select_first, int select_last)
{
int res0 = NativeScript.ScriptStringOut
(ssa_struct_ptr,
ReferensePoint.X,
ReferensePoint.Y,
GDI_ExtTextOutOption.None,
IntPtr.Zero,
select_first,
select_last,
false);
if (res0 != NativeScript.S_OK)
{
Marshal.ThrowExceptionForHR(res0);
}
}
public void PrepareLayout(IntPtr hdc, IntPtr char_buffer, int max_char_len, int max_width)
{
ssa_struct_ptr = NativeScript.ScriptStringAnalyseCall
(hdc,
char_buffer,
max_char_len,
max_width,
tab_def);
//сколько поместилось
int chars_clipped = NativeScript.GetPcOutChars(ssa_struct_ptr);
//просматриваем с конца для поиска разрыва линии
IntPtr attr_buffer = NativeScript.ScriptString_pLogAttr(ssa_struct_ptr);
int line_break_ind = -1;
//если вся строка уместилась в линию
if (chars_clipped == max_char_len)
{
line_break_ind = chars_clipped - 1;
}
//если вся строка не уместилась, ищем крайний с конца SoftBreak
if (line_break_ind == -1)
{
LogicalCharacterAttribute attr = LogicalCharacterAttribute.None;
for (int i = chars_clipped - 1; i > 0; i--)
{
attr = NativeScript.GetCharacterAttribute(attr_buffer, i);
if ((attr & LogicalCharacterAttribute.SoftBreak) == LogicalCharacterAttribute.SoftBreak)
{
line_break_ind = i - 1;
break;
}
}
}
//если и softBreak не найден, рвем по умещению
if (line_break_ind == -1)
{
line_break_ind = chars_clipped - 1;
}
//если разрываем, вторично вызываем обссчет с новой длиной строки
if (line_break_ind + 1 != max_char_len)
{
//освобождаем предыдущий ssa_sctuct_ptr
int res3 = NativeScript.ScriptStringFree(ref ssa_struct_ptr);
if (res3 != 0)
{
Marshal.ThrowExceptionForHR(res3);
}
//и обновляем
ssa_struct_ptr = NativeScript.ScriptStringAnalyseCall
(hdc,
char_buffer,
line_break_ind + 1,
tab_def);
}
//debug
//string actual_string = Marshal.PtrToStringAuto(char_buffer, line_break_ind + 1);
//char[] actual_chars = actual_string.ToCharArray();
//заполняем свойства
Extent = NativeScript.GetScriptStringExtent(ssa_struct_ptr);
CharLength = line_break_ind + 1;
//debug
//if (Extent.Width == 0)
//{
// int debug = 0;
//}
}
public LogicalCharacterAttribute GetLogicalAttribute(int char_index)
{
IntPtr log_attr_buffer = NativeScript.ScriptString_pLogAttr(ssa_struct_ptr);
return(NativeScript.GetCharacterAttribute(log_attr_buffer, char_index));
}
public int FindPreviousLineStart(IDeviceContext dev)
{
//для обсчета строки будет нужен контекст
IntPtr hdc = dev.GetHdc();
IntPtr font_ptr = Font.ToHfont();
IntPtr old_font = NativeGdi.SelectObject(hdc, font_ptr);
uint old_align = NativeGdi.SetTextAlign(hdc, 0);
int line_height = (int)Math.Ceiling(Font.GetHeight());
IntPtr char_buffer = IntPtr.Zero;
bool EOF = false;
int chars_filled = 0;
int ret = 0;
//получаем буфер символов начиная от -max_chars_in_line
OnFetchCharsToScreen
(-max_chars_in_line,
false,
out char_buffer,
out chars_filled,
out EOF);
if (chars_filled <= 0)
{
//то есть и так находимся в начале
ret = 0;
}
else
{
//получаем ssa_sctruct
IntPtr ssa_scruct = NativeScript.ScriptStringAnalyseCall
(hdc,
char_buffer,
chars_filled,
SCRIPT_TABDEF.GetDefault());
//берем logical wodths
int[] widths = NativeScript.GetLogicalWidths(ssa_scruct);
//освобождаем ssa_scruct
NativeScript.ScriptStringFree(ref ssa_scruct);
//суммируем полученные ширины символов с конца, пока не превысим
//максимальную ширину или не встретим второй hard break
char current_char = '\0';
int current_width = 0;
int finding_ind = -1;
for (int i = chars_filled - 1; i >= 0; i--)
{
current_char = get_char_from_buffer(char_buffer, i);
current_width = current_width + widths[i];
//проверяем ширину
if (current_width > Bounds.Width)
{
finding_ind = i;
break;
}
//проверяем hard break (\n \r \r\n) начиная со второго шага
if (i != chars_filled - 1)
{
if (current_char == '\n')
{
if (((i - 1) >= 0) && (get_char_from_buffer(char_buffer, i - 1) == '\r'))
{
finding_ind = i;
break;
}
finding_ind = i;
break;
}
else if ((current_char == '\r') && (i < chars_filled - 2))
{
finding_ind = i;
break;
}
}
}
//finding_ind теперь соответствует концу предыщей строки
ret = -(chars_filled - finding_ind - 1);
}
font_ptr = NativeGdi.SelectObject(hdc, old_font);
NativeGdi.DeleteObject(font_ptr);
NativeGdi.SetTextAlign(hdc, old_align);
dev.ReleaseHdc();
return(ret);
}