void text_layout::break_line(std::pair<unsigned, unsigned> && line_limits)
{
text_line line(line_limits.first, line_limits.second);
shape_text(line);
double scaled_wrap_width = wrap_width_ * scale_factor_;
if (!scaled_wrap_width || line.width() < scaled_wrap_width)
{
add_line(std::move(line));
return;
}
if (text_ratio_)
{
double wrap_at;
double string_width = line.width();
double string_height = line.line_height();
for (double i = 1.0; ((wrap_at = string_width/i)/(string_height*i)) > text_ratio_ && (string_width/i) > scaled_wrap_width; i += 1.0) ;
scaled_wrap_width = wrap_at;
}
mapnik::value_unicode_string const& text = itemizer_.text();
line_breaker breaker(text, wrap_char_);
double current_line_length = 0;
int last_break_position = static_cast<int>(line.first_char());
for (unsigned i=line.first_char(); i < line.last_char(); ++i)
{
std::map<unsigned, double>::const_iterator width_itr = width_map_.find(i);
if (width_itr != width_map_.end())
{
current_line_length += width_itr->second;
}
if (current_line_length <= scaled_wrap_width) continue;
int break_position = wrap_before_ ? breaker.preceding(i + 1) : breaker.following(i);
if (break_position <= last_break_position || break_position == static_cast<int>(BreakIterator::DONE))
{
break_position = breaker.following(i);
if (break_position == static_cast<int>(BreakIterator::DONE))
{
break_position = line.last_char();
}
}
if (break_position < static_cast<int>(line.first_char()))
{
break_position = line.first_char();
}
if (break_position > static_cast<int>(line.last_char()))
{
break_position = line.last_char();
}
text_line new_line(adjust_last_break_position(last_break_position, repeat_wrap_char_), break_position);
clear_cluster_widths(adjust_last_break_position(last_break_position, repeat_wrap_char_), break_position);
shape_text(new_line);
add_line(std::move(new_line));
last_break_position = break_position;
i = break_position - 1;
current_line_length = 0;
}
if (last_break_position == static_cast<int>(line.first_char()))
{
add_line(std::move(line));
}
else if (last_break_position != static_cast<int>(line.last_char()))
{
text_line new_line(adjust_last_break_position(last_break_position, repeat_wrap_char_), line.last_char());
clear_cluster_widths(adjust_last_break_position(last_break_position, repeat_wrap_char_), line.last_char());
shape_text(new_line);
add_line(std::move(new_line));
}
}
static av_cold int init(AVFilterContext *ctx)
{
int err;
DrawTextContext *s = ctx->priv;
Glyph *glyph;
if (!s->fontfile && !CONFIG_LIBFONTCONFIG) {
av_log(ctx, AV_LOG_ERROR, "No font filename provided\n");
return AVERROR(EINVAL);
}
if (s->textfile) {
if (s->text) {
av_log(ctx, AV_LOG_ERROR,
"Both text and text file provided. Please provide only one\n");
return AVERROR(EINVAL);
}
if ((err = load_textfile(ctx)) < 0)
return err;
}
if (s->reload && !s->textfile)
av_log(ctx, AV_LOG_WARNING, "No file to reload\n");
if (s->tc_opt_string) {
int ret = av_timecode_init_from_string(&s->tc, s->tc_rate,
s->tc_opt_string, ctx);
if (ret < 0)
return ret;
if (s->tc24hmax)
s->tc.flags |= AV_TIMECODE_FLAG_24HOURSMAX;
if (!s->text)
s->text = av_strdup("");
}
if (!s->text) {
av_log(ctx, AV_LOG_ERROR,
"Either text, a valid file or a timecode must be provided\n");
return AVERROR(EINVAL);
}
#if CONFIG_LIBFRIBIDI
if (s->text_shaping)
if ((err = shape_text(ctx)) < 0)
return err;
#endif
if ((err = FT_Init_FreeType(&(s->library)))) {
av_log(ctx, AV_LOG_ERROR,
"Could not load FreeType: %s\n", FT_ERRMSG(err));
return AVERROR(EINVAL);
}
err = load_font(ctx);
if (err)
return err;
if (!s->fontsize)
s->fontsize = 16;
if ((err = FT_Set_Pixel_Sizes(s->face, 0, s->fontsize))) {
av_log(ctx, AV_LOG_ERROR, "Could not set font size to %d pixels: %s\n",
s->fontsize, FT_ERRMSG(err));
return AVERROR(EINVAL);
}
if (s->borderw) {
if (FT_Stroker_New(s->library, &s->stroker)) {
av_log(ctx, AV_LOG_ERROR, "Coult not init FT stroker\n");
return AVERROR_EXTERNAL;
}
FT_Stroker_Set(s->stroker, s->borderw << 6, FT_STROKER_LINECAP_ROUND,
FT_STROKER_LINEJOIN_ROUND, 0);
}
s->use_kerning = FT_HAS_KERNING(s->face);
/* load the fallback glyph with code 0 */
load_glyph(ctx, NULL, 0);
/* set the tabsize in pixels */
if ((err = load_glyph(ctx, &glyph, ' ')) < 0) {
av_log(ctx, AV_LOG_ERROR, "Could not set tabsize.\n");
return err;
}
s->tabsize *= glyph->advance;
if (s->exp_mode == EXP_STRFTIME &&
(strchr(s->text, '%') || strchr(s->text, '\\')))
av_log(ctx, AV_LOG_WARNING, "expansion=strftime is deprecated.\n");
av_bprint_init(&s->expanded_text, 0, AV_BPRINT_SIZE_UNLIMITED);
av_bprint_init(&s->expanded_fontcolor, 0, AV_BPRINT_SIZE_UNLIMITED);
return 0;
}
// In the Unicode string characters are always stored in logical order.
// This makes line breaking easy. One word is added to the current line at a time. Once the line is too long
// we either go back one step or insert the line break at the current position (depending on "wrap_before" setting).
// At the end everything that is left over is added as the final line.
void text_layout::break_line_icu(std::pair<unsigned, unsigned> && line_limits)
{
text_line line(line_limits.first, line_limits.second);
shape_text(line);
double scaled_wrap_width = wrap_width_ * scale_factor_;
if (scaled_wrap_width <= 0 || line.width() < scaled_wrap_width)
{
add_line(std::move(line));
return;
}
if (text_ratio_ > 0)
{
double wrap_at;
double string_width = line.width();
double string_height = line.line_height();
for (double i = 1.0;
((wrap_at = string_width/i)/(string_height*i)) > text_ratio_ && (string_width/i) > scaled_wrap_width;
i += 1.0) ;
scaled_wrap_width = wrap_at;
}
mapnik::value_unicode_string const& text = itemizer_.text();
Locale locale; // TODO: Is the default constructor correct?
UErrorCode status = U_ZERO_ERROR;
std::unique_ptr<BreakIterator> breakitr(BreakIterator::createLineInstance(locale, status));
// Not breaking the text if an error occurs is probably the best thing we can do.
// https://github.com/mapnik/mapnik/issues/2072
if (!U_SUCCESS(status))
{
add_line(std::move(line));
MAPNIK_LOG_ERROR(text_layout) << " could not create BreakIterator: " << u_errorName(status);
return;
}
breakitr->setText(text);
double current_line_length = 0;
int last_break_position = static_cast<int>(line.first_char());
for (unsigned i = line.first_char(); i < line.last_char(); ++i)
{
// TODO: character_spacing
std::map<unsigned, double>::const_iterator width_itr = width_map_.find(i);
if (width_itr != width_map_.end())
{
current_line_length += width_itr->second;
}
if (current_line_length <= scaled_wrap_width) continue;
int break_position = wrap_before_ ? breakitr->preceding(i + 1) : breakitr->following(i);
// following() returns a break position after the last word. So DONE should only be returned
// when calling preceding.
if (break_position <= last_break_position || break_position == static_cast<int>(BreakIterator::DONE))
{
// A single word is longer than the maximum line width.
// Violate line width requirement and choose next break position
break_position = breakitr->following(i);
if (break_position == static_cast<int>(BreakIterator::DONE))
{
break_position = line.last_char();
MAPNIK_LOG_ERROR(text_layout) << "Unexpected result in break_line. Trying to recover...\n";
}
}
// Break iterator operates on the whole string, while we only look at one line. So we need to
// clamp break values.
if (break_position < static_cast<int>(line.first_char()))
{
break_position = line.first_char();
}
if (break_position > static_cast<int>(line.last_char()))
{
break_position = line.last_char();
}
bool adjust_for_space_character = break_position > 0 && text[break_position - 1] == 0x0020;
text_line new_line(last_break_position, adjust_for_space_character ? break_position - 1 : break_position);
clear_cluster_widths(last_break_position, adjust_for_space_character ? break_position - 1 : break_position);
shape_text(new_line);
add_line(std::move(new_line));
last_break_position = break_position;
i = break_position - 1;
current_line_length = 0;
}
if (last_break_position == static_cast<int>(line.first_char()))
{
// No line breaks => no reshaping required
add_line(std::move(line));
}
else if (last_break_position != static_cast<int>(line.last_char()))
{
text_line new_line(last_break_position, line.last_char());
clear_cluster_widths(last_break_position, line.last_char());
shape_text(new_line);
add_line(std::move(new_line));
}
}
