X-Git-Url: https://main.carlh.net/gitweb/?a=blobdiff_plain;f=src%2Flib%2Frender_text.cc;h=6f7614d36f5050b4bde1f9c553c59d5827110f7f;hb=0330b684fe616b465e65b67f7d995e659fa83fca;hp=94b41285627270868d97a95792659445cae102ce;hpb=952084c4221c5708e02c783284cf0f7239c6b4c4;p=dcpomatic.git diff --git a/src/lib/render_text.cc b/src/lib/render_text.cc index 94b412856..6f7614d36 100644 --- a/src/lib/render_text.cc +++ b/src/lib/render_text.cc @@ -55,28 +55,81 @@ static FcConfig* fc_config = nullptr; static list> fc_config_fonts; +/** Create a Pango layout using a dummy context which we can use to calculate the size + * of the text we will render. Then we can transfer the layout over to the real context + * for the actual render. + */ +static Glib::RefPtr +create_layout() +{ + auto c_font_map = pango_cairo_font_map_new (); + DCPOMATIC_ASSERT (c_font_map); + auto font_map = Glib::wrap (c_font_map); + auto c_context = pango_font_map_create_context (c_font_map); + DCPOMATIC_ASSERT (c_context); + auto context = Glib::wrap (c_context); + return Pango::Layout::create (context); +} + + +static void +setup_layout (Glib::RefPtr layout, string font_name, string markup) +{ + layout->set_alignment (Pango::ALIGN_LEFT); + Pango::FontDescription font (font_name); + layout->set_font_description (font); + layout->set_markup (markup); +} + + string -marked_up (list subtitles, int target_height, float fade_factor) +marked_up (list subtitles, int target_height, float fade_factor, string font_name) { - string out; + auto constexpr pixels_to_1024ths_point = 72 * 1024 / 96; - for (auto const& i: subtitles) { - out += "(i.size_in_pixels(target_height) * 72 * 1024 / 96) + "\" "; + span += "size=\"" + dcp::raw_convert(subtitle.size_in_pixels(target_height) * pixels_to_1024ths_point) + "\" "; /* Between 1-65535 inclusive, apparently... */ - out += "alpha=\"" + dcp::raw_convert(int(floor(fade_factor * 65534)) + 1) + "\" "; - out += "color=\"#" + i.colour().to_rgb_string() + "\">"; - out += i.text(); - out += ""; + span += "alpha=\"" + dcp::raw_convert(int(floor(fade_factor * 65534)) + 1) + "\" "; + span += "color=\"#" + subtitle.colour().to_rgb_string() + "\""; + if (!extra_attribute.empty()) { + span += " " + extra_attribute; + } + span += ">"; + span += text; + span += ""; + return span; + }; + + string out; + for (auto const& i: subtitles) { + if (std::abs(i.space_before()) > dcp::SPACE_BEFORE_EPSILON) { + /* We need to insert some horizontal space into the layout. The only way I can find to do this + * is to write a " " with some special letter_spacing. As far as I can see, such a space will + * be written with letter_spacing either side. This means that to get a horizontal space x we + * need to write a " " with letter spacing (x - s) / 2, where s is the width of the " ". + */ + auto layout = create_layout(); + setup_layout(layout, font_name, make_span(i, " ", {})); + int space_width; + int dummy; + layout->get_pixel_size(space_width, dummy); + auto spacing = ((i.space_before() * i.size_in_pixels(target_height) - space_width) / 2) * pixels_to_1024ths_point; + out += make_span(i, " ", "letter_spacing=\"" + dcp::raw_convert(spacing) + "\""); + } + + out += make_span(i, i.text(), {}); } return out; @@ -191,19 +244,30 @@ calculate_fade_factor (StringText const& first, DCPTime time, int frame_rate) */ auto const fade_in_start = DCPTime::from_seconds(first.in().as_seconds()).round(frame_rate); auto const fade_in_end = fade_in_start + DCPTime::from_seconds (first.fade_up_time().as_seconds ()); - auto const fade_out_end = DCPTime::from_seconds (first.out().as_seconds()).round(frame_rate); - auto const fade_out_start = fade_out_end - DCPTime::from_seconds (first.fade_down_time().as_seconds ()); if (fade_in_start <= time && time <= fade_in_end && fade_in_start != fade_in_end) { fade_factor *= DCPTime(time - fade_in_start).seconds() / DCPTime(fade_in_end - fade_in_start).seconds(); } - if (fade_out_start <= time && time <= fade_out_end && fade_out_start != fade_out_end) { - fade_factor *= 1 - DCPTime(time - fade_out_start).seconds() / DCPTime(fade_out_end - fade_out_start).seconds(); - } - if (time < fade_in_start || time > fade_out_end) { + + if (time < fade_in_start) { fade_factor = 0; } + /* first.out() may be zero if we don't know when this subtitle will finish. We can only think about + * fading out if we _do_ know when it will finish. + */ + if (first.out() != dcp::Time()) { + auto const fade_out_end = DCPTime::from_seconds (first.out().as_seconds()).round(frame_rate); + auto const fade_out_start = fade_out_end - DCPTime::from_seconds(first.fade_down_time().as_seconds()); + + if (fade_out_start <= time && time <= fade_out_end && fade_out_start != fade_out_end) { + fade_factor *= 1 - DCPTime(time - fade_out_start).seconds() / DCPTime(fade_out_end - fade_out_start).seconds(); + } + if (time > fade_out_end) { + fade_factor = 0; + } + } + return fade_factor; } @@ -259,33 +323,6 @@ y_position (StringText const& first, int target_height, int layout_height) } -static void -setup_layout (Glib::RefPtr layout, string font_name, string markup) -{ - layout->set_alignment (Pango::ALIGN_LEFT); - Pango::FontDescription font (font_name); - layout->set_font_description (font); - layout->set_markup (markup); -} - - -/** Create a Pango layout using a dummy context which we can use to calculate the size - * of the text we will render. Then we can transfer the layout over to the real context - * for the actual render. - */ -static Glib::RefPtr -create_layout() -{ - auto c_font_map = pango_cairo_font_map_new (); - DCPOMATIC_ASSERT (c_font_map); - auto font_map = Glib::wrap (c_font_map); - auto c_context = pango_font_map_create_context (c_font_map); - DCPOMATIC_ASSERT (c_context); - auto context = Glib::wrap (c_context); - return Pango::Layout::create (context); -} - - /** @param subtitles A list of subtitles that are all on the same line, * at the same time and with the same fade in/out. */ @@ -301,7 +338,7 @@ render_line (list subtitles, list> fonts, dcp::Size auto const font_name = setup_font (first, fonts); auto const fade_factor = calculate_fade_factor (first, time, frame_rate); - auto const markup = marked_up (subtitles, target.height, fade_factor); + auto const markup = marked_up (subtitles, target.height, fade_factor, font_name); auto layout = create_layout (); setup_layout (layout, font_name, markup); dcp::Size size;