lyx_mirror/src/Bidi.cpp

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/**
* \file Bidi.cpp
* This file is part of LyX, the document processor.
* Licence details can be found in the file COPYING.
*
* \author Dekel Tsur
*
* Full author contact details are available in file CREDITS.
*/
#include <config.h>
#include "Bidi.h"
#include "Buffer.h"
#include "BufferView.h"
#include "Cursor.h"
#include "Font.h"
#include "Row.h"
#include "LyXRC.h"
#include "Paragraph.h"
namespace lyx {
pos_type Bidi::log2vis(pos_type pos) const
{
return (start_ == -1) ? pos : log2vis_list_[pos - start_];
}
pos_type Bidi::vis2log(pos_type pos) const
{
return (start_ == -1) ? pos : vis2log_list_[pos - start_];
}
pos_type Bidi::level(pos_type pos) const
{
return (start_ == -1) ? 0 : levels_[pos - start_];
}
bool Bidi::inRange(pos_type pos) const
{
return start_ == -1 || (start_ <= pos && pos <= end_);
}
bool Bidi::same_direction() const
{
return same_direction_;
}
void Bidi::computeTables(Paragraph const & par,
Buffer const & buf, Row const & row)
{
same_direction_ = true;
if (!lyxrc.rtl_support) {
start_ = -1;
return;
}
if (par.inInset().forceLTR()) {
start_ = -1;
return;
}
start_ = row.pos();
end_ = row.endpos() - 1;
if (start_ > end_) {
start_ = -1;
return;
}
if (end_ + 2 - start_ >
static_cast<pos_type>(log2vis_list_.size())) {
pos_type new_size =
(end_ + 2 - start_ < 500) ?
500 : 2 * (end_ + 2 - start_);
log2vis_list_.resize(new_size);
vis2log_list_.resize(new_size);
levels_.resize(new_size);
}
vis2log_list_[end_ + 1 - start_] = -1;
log2vis_list_[end_ + 1 - start_] = -1;
BufferParams const & bufparams = buf.params();
pos_type stack[2];
bool const rtl_par = par.isRTL(bufparams);
int lev = 0;
bool rtl = false;
bool rtl0 = false;
pos_type const body_pos = par.beginOfBody();
for (pos_type lpos = start_; lpos <= end_; ++lpos) {
bool is_space = false;
// We do not handle spaces around an RTL segment in a special way anymore.
// Neither do we do so when generating the LaTeX, so setting is_space
// to false makes the view in the GUI consistent with the output of LaTeX
// later. The old setting was:
//bool is_space = par.isLineSeparator(lpos);
// FIXME: once we're sure that this is what we really want, we should just
// get rid of this variable...
pos_type const pos =
(is_space && lpos + 1 <= end_ &&
!par.isLineSeparator(lpos + 1) &&
!par.isNewline(lpos + 1))
? lpos + 1 : lpos;
Font const * font = &(par.getFontSettings(bufparams, pos));
if (pos != lpos && 0 < lpos && rtl0 && font->isRightToLeft() &&
font->fontInfo().number() == FONT_ON &&
par.getFontSettings(bufparams, lpos - 1).fontInfo().number()
== FONT_ON) {
font = &(par.getFontSettings(bufparams, lpos));
is_space = false;
}
bool new_rtl = font->isVisibleRightToLeft();
bool new_rtl0 = font->isRightToLeft();
int new_level;
if (lpos == body_pos - 1
&& row.pos() < body_pos - 1
&& is_space) {
new_level = rtl_par ? 1 : 0;
new_rtl0 = rtl_par;
new_rtl = rtl_par;
} else if (new_rtl0) {
new_level = new_rtl ? 1 : 2;
} else {
new_level = rtl_par ? 2 : 0;
}
if (is_space && new_level >= lev) {
new_level = lev;
new_rtl = rtl;
new_rtl0 = rtl0;
}
int new_level2 = new_level;
if (lev == new_level && rtl0 != new_rtl0) {
--new_level2;
log2vis_list_[lpos - start_] = rtl ? 1 : -1;
} else if (lev < new_level) {
log2vis_list_[lpos - start_] = rtl ? -1 : 1;
if (new_level > 0 && !rtl_par)
same_direction_ = false;
} else {
log2vis_list_[lpos - start_] = new_rtl ? -1 : 1;
}
rtl = new_rtl;
rtl0 = new_rtl0;
levels_[lpos - start_] = new_level;
while (lev > new_level2) {
pos_type old_lpos = stack[--lev];
int delta = lpos - old_lpos - 1;
if (lev % 2)
delta = -delta;
log2vis_list_[lpos - start_] += delta;
log2vis_list_[old_lpos - start_] += delta;
}
while (lev < new_level)
stack[lev++] = lpos;
}
while (lev > 0) {
pos_type const old_lpos = stack[--lev];
int delta = end_ - old_lpos;
if (lev % 2)
delta = -delta;
log2vis_list_[old_lpos - start_] += delta;
}
pos_type vpos = start_ - 1;
for (pos_type lpos = start_; lpos <= end_; ++lpos) {
vpos += log2vis_list_[lpos - start_];
vis2log_list_[vpos - start_] = lpos;
log2vis_list_[lpos - start_] = vpos;
}
}
// This method requires a previous call to computeTables()
bool Bidi::isBoundary(Buffer const & buf, Paragraph const & par,
pos_type pos) const
{
if (!lyxrc.rtl_support || pos == 0)
return false;
if (!inRange(pos - 1)) {
// This can happen if pos is the first char of a row.
// Returning false in this case is incorrect!
return false;
}
bool const rtl = level(pos - 1) % 2;
bool const rtl2 = inRange(pos)
? level(pos) % 2
: par.isRTL(buf.params());
return rtl != rtl2;
}
bool Bidi::isBoundary(Buffer const & buf, Paragraph const & par,
pos_type pos, Font const & font) const
{
if (!lyxrc.rtl_support)
return false; // This is just for speedup
bool const rtl = font.isVisibleRightToLeft();
bool const rtl2 = inRange(pos)
? level(pos) % 2
: par.isRTL(buf.params());
return rtl != rtl2;
}
bool reverseDirectionNeeded(Cursor const & cur)
{
/*
* We determine the directions based on the direction of the
* bottom() --- i.e., outermost --- paragraph, because that is
* the only way to achieve consistency of the arrow's movements
* within a paragraph, and thus avoid situations in which the
* cursor gets stuck.
*/
return cur.bottom().paragraph().isRTL(cur.bv().buffer().params());
}
bool isWithinRtlParagraph(Cursor const & cur)
{
return cur.innerParagraph().isRTL(cur.bv().buffer().params());
}
} // namespace lyx