void Label::update_text_cache()
{
// try and render with a font cache
if (cache_is_dirty)
{
Renderer* renderer = get_compositor()->get_renderer();
size_t height;
int ascender, descender;
renderer->font_metrics(font_handle, height, ascender, descender);
content_bounds.origin = origin + scroll_offset;
cache_is_dirty = 0;
font_cache.clear(false);
size_t last_start = 0;
glm::vec2 origin_offset = glm::vec2(LABEL_LEFT_MARGIN, LABEL_TOP_MARGIN);
origin_offset.y += font_height;
content_bounds.size.width = size.width;
content_bounds.size.height = -font_height;
const bool enable_word_wrap = true;
// keep track of the last segment in text to handle word wraps.
size_t last_word_break = 0;
const size_t character_count = text.size();
for (size_t index = 0; index < character_count+1; ++index)
{
const bool is_last_character = (index == character_count);
Rect text_bounds;
if (text[index] == '\n' || is_last_character)
{
create_cache_entry(index, last_start, origin_offset);
if (is_last_character)
{
break;
}
}
else if (enable_word_wrap && (text[index] == ' '))
{
renderer->font_measure_string(font_handle, &text[last_start], (index - last_start), text_bounds);
float test_width = content_bounds.width();
if (has_vertical_scrollbar())
{
test_width -= vertical_bar->get_size().width;
}
if (text_bounds.width() > test_width)
{
// we need to wrap text starting from last index;
create_cache_entry(last_word_break, last_start, origin_offset);
// reset index, last_start. Advance it past the space.
index = (last_word_break + 1);
last_start = (index + 1);
}
last_word_break = index;
}
}
}
} // update_text_cache
/**
* Tries to use a vertical scrollbar with the widget.
*
* @todo implement this function properly.
*
* @param maximum_height The wanted maximum height of the widget.
*
* @pre has_vertical_scrollbar() == true.
*/
virtual void layout_use_vertical_scrollbar(const unsigned /*maximum_height*/)
{ assert(has_vertical_scrollbar()); }
