Fix subtitle vertical position (#2367).
[dcpomatic.git] / src / lib / render_text.cc
index 6f7614d36f5050b4bde1f9c553c59d5827110f7f..d3db4ac1940c245987d16c4f055e632d82f2cec7 100644 (file)
 #include "cross.h"
 #include "dcpomatic_assert.h"
 #include "font.h"
+#include "font_config.h"
 #include "image.h"
 #include "render_text.h"
 #include "types.h"
 #include "util.h"
-#include "warnings.h"
 #include <dcp/raw_convert.h>
-#include <fontconfig/fontconfig.h>
+#include <dcp/warnings.h>
 #include <cairomm/cairomm.h>
-DCPOMATIC_DISABLE_WARNINGS
+LIBDCP_DISABLE_WARNINGS
 #include <pangomm.h>
-DCPOMATIC_ENABLE_WARNINGS
+LIBDCP_ENABLE_WARNINGS
 #include <pango/pangocairo.h>
 #include <boost/algorithm/string.hpp>
 #include <iostream>
@@ -51,10 +51,6 @@ using std::string;
 using namespace dcpomatic;
 
 
-static FcConfig* fc_config = nullptr;
-static list<pair<boost::filesystem::path, string>> 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.
@@ -99,7 +95,7 @@ marked_up (list<StringText> subtitles, int target_height, float fade_factor, str
                if (subtitle.underline()) {
                        span += "underline=\"single\" ";
                }
-               span += "size=\"" + dcp::raw_convert<string>(subtitle.size_in_pixels(target_height) * pixels_to_1024ths_point) + "\" ";
+               span += "size=\"" + dcp::raw_convert<string>(lrintf(subtitle.size_in_pixels(target_height) * pixels_to_1024ths_point)) + "\" ";
                /* Between 1-65535 inclusive, apparently... */
                span += "alpha=\"" + dcp::raw_convert<string>(int(floor(fade_factor * 65534)) + 1) + "\" ";
                span += "color=\"#" + subtitle.colour().to_rgb_string() + "\"";
@@ -175,62 +171,15 @@ create_surface (shared_ptr<Image> image)
 
 
 static string
-setup_font (StringText const& subtitle, list<shared_ptr<Font>> const& fonts)
+setup_font(shared_ptr<const dcpomatic::Font> font)
 {
-       if (!fc_config) {
-               fc_config = FcInitLoadConfig ();
-       }
-
        auto font_file = default_font_file ();
 
-       for (auto i: fonts) {
-               if (i->id() == subtitle.font() && i->file()) {
-                       font_file = i->file().get();
-               }
-       }
-
-       auto existing = fc_config_fonts.cbegin ();
-       while (existing != fc_config_fonts.end() && existing->first != font_file) {
-               ++existing;
-       }
-
-       string font_name;
-       if (existing != fc_config_fonts.end ()) {
-               font_name = existing->second;
-       } else {
-               /* Make this font available to DCP-o-matic */
-               FcConfigAppFontAddFile (fc_config, reinterpret_cast<FcChar8 const *>(font_file.string().c_str()));
-               auto pattern = FcPatternBuild (
-                       0, FC_FILE, FcTypeString, font_file.string().c_str(), static_cast<char *>(0)
-                       );
-               auto object_set = FcObjectSetBuild (FC_FAMILY, FC_STYLE, FC_LANG, FC_FILE, static_cast<char *> (0));
-               auto font_set = FcFontList (fc_config, pattern, object_set);
-               if (font_set) {
-                       for (int i = 0; i < font_set->nfont; ++i) {
-                               FcPattern* font = font_set->fonts[i];
-                               FcChar8* file;
-                               FcChar8* family;
-                               FcChar8* style;
-                               if (
-                                       FcPatternGetString (font, FC_FILE, 0, &file) == FcResultMatch &&
-                                       FcPatternGetString (font, FC_FAMILY, 0, &family) == FcResultMatch &&
-                                       FcPatternGetString (font, FC_STYLE, 0, &style) == FcResultMatch
-                                       ) {
-                                       font_name = reinterpret_cast<char const *> (family);
-                               }
-                       }
-
-                       FcFontSetDestroy (font_set);
-               }
-
-               FcObjectSetDestroy (object_set);
-               FcPatternDestroy (pattern);
-
-               fc_config_fonts.push_back (make_pair(font_file, font_name));
+       if (font && font->file()) {
+               font_file = *font->file();
        }
 
-       FcConfigSetCurrent (fc_config);
-       return font_name;
+       return FontConfig::instance()->make_font_available(font_file);
 }
 
 
@@ -296,27 +245,41 @@ x_position (StringText const& first, int target_width, int layout_width)
 
 
 static int
-y_position (StringText const& first, int target_height, int layout_height)
+y_position (StringText const& first, int target_height, int baseline_to_bottom, int layout_height)
 {
        int y = 0;
-       switch (first.v_align()) {
-       case dcp::VAlign::TOP:
-               /* SMPTE says that v_position is the distance between top
-                  of frame and top of subtitle, but this doesn't always seem to be
-                  the case in practice; Gunnar Ásgeirsson's Dolby server appears
-                  to put VAlign::TOP subs with v_position as the distance between top
-                  of frame and bottom of subtitle.
-               */
-               y = first.v_position() * target_height - layout_height;
-               break;
-       case dcp::VAlign::CENTER:
-               /* v_position is distance between centre of frame and centre of subtitle */
-               y = (0.5 + first.v_position()) * target_height - layout_height / 2;
-               break;
-       case dcp::VAlign::BOTTOM:
-               /* v_position is distance between bottom of frame and bottom of subtitle */
-               y = (1.0 - first.v_position()) * target_height - layout_height;
+       switch (first.valign_standard) {
+       case dcp::Standard::INTEROP:
+               switch (first.v_align()) {
+               case dcp::VAlign::TOP:
+                       /* v_position is distance from top of frame to subtitle baseline */
+                       y = first.v_position() * target_height - (layout_height - baseline_to_bottom);
+                       break;
+               case dcp::VAlign::CENTER:
+                       /* v_position is distance from centre of frame to subtitle baseline */
+                       y = (0.5 + first.v_position()) * target_height - (layout_height - baseline_to_bottom);
+                       break;
+               case dcp::VAlign::BOTTOM:
+                       /* v_position is distance from bottom of frame to subtitle baseline */
+                       y = (1.0 - first.v_position()) * target_height - (layout_height - baseline_to_bottom);
+                       break;
+               }
                break;
+       case dcp::Standard::SMPTE:
+               switch (first.v_align()) {
+               case dcp::VAlign::TOP:
+                       /* v_position is distance from top of frame to top of subtitle */
+                       y = first.v_position() * target_height;
+                       break;
+               case dcp::VAlign::CENTER:
+                       /* v_position is distance from centre of frame to centre of subtitle */
+                       y = (0.5 + first.v_position()) * target_height - layout_height / 2;
+                       break;
+               case dcp::VAlign::BOTTOM:
+                       /* v_position is distance from bottom of frame to bottom of subtitle */
+                       y = (1.0 - first.v_position()) * target_height - layout_height;
+                       break;
+               }
        }
 
        return y;
@@ -327,7 +290,7 @@ y_position (StringText const& first, int target_height, int layout_height)
  *  at the same time and with the same fade in/out.
  */
 static PositionImage
-render_line (list<StringText> subtitles, list<shared_ptr<Font>> fonts, dcp::Size target, DCPTime time, int frame_rate)
+render_line (list<StringText> subtitles, dcp::Size target, DCPTime time, int frame_rate)
 {
        /* XXX: this method can only handle italic / bold changes mid-line,
           nothing else yet.
@@ -336,13 +299,13 @@ render_line (list<StringText> subtitles, list<shared_ptr<Font>> fonts, dcp::Size
        DCPOMATIC_ASSERT (!subtitles.empty ());
        auto const& first = subtitles.front ();
 
-       auto const font_name = setup_font (first, fonts);
+       auto const font_name = setup_font(first.font);
        auto const fade_factor = calculate_fade_factor (first, time, frame_rate);
        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;
-       layout->get_pixel_size (size.width, size.height);
+       auto ink = layout->get_ink_extents();
+       dcp::Size size{ink.get_width() / Pango::SCALE, ink.get_height() / Pango::SCALE};
 
        /* Calculate x and y scale factors.  These are only used to stretch
           the font away from its normal aspect ratio.
@@ -367,12 +330,8 @@ render_line (list<StringText> subtitles, list<shared_ptr<Font>> fonts, dcp::Size
        size.height *= y_scale;
 
        /* Shuffle the subtitle over by the border width (if we have any) so it's not cut off */
-       int const x_offset = ceil (border_width);
-       /* Move down a bit so that accents on capital letters can be seen */
-       int const y_offset = target.height / 100.0;
-
-       size.width += x_offset;
-       size.height += y_offset;
+       int const x_offset = (-ink.get_x() / Pango::SCALE) + ceil(border_width);
+       int const y_offset = -ink.get_y() / Pango::SCALE + ceil(border_width);
 
        auto image = create_image (size);
        auto surface = create_surface (image);
@@ -414,7 +373,7 @@ render_line (list<StringText> subtitles, list<shared_ptr<Font>> fonts, dcp::Size
        context->stroke ();
 
        int const x = x_position (first, target.width, size.width);
-       int const y = y_position (first, target.height, size.height);
+       int const y = y_position (first, target.height, ink.get_y() / Pango::SCALE, size.height);
        return PositionImage (image, Position<int>(max (0, x), max(0, y)));
 }
 
@@ -424,22 +383,82 @@ render_line (list<StringText> subtitles, list<shared_ptr<Font>> fonts, dcp::Size
  *  @param frame_rate DCP frame rate.
  */
 list<PositionImage>
-render_text (list<StringText> subtitles, list<shared_ptr<Font>> fonts, dcp::Size target, DCPTime time, int frame_rate)
+render_text (list<StringText> subtitles, dcp::Size target, DCPTime time, int frame_rate)
 {
        list<StringText> pending;
        list<PositionImage> images;
 
        for (auto const& i: subtitles) {
                if (!pending.empty() && (i.v_align() != pending.back().v_align() || fabs(i.v_position() - pending.back().v_position()) > 1e-4)) {
-                       images.push_back (render_line (pending, fonts, target, time, frame_rate));
+                       images.push_back(render_line(pending, target, time, frame_rate));
                        pending.clear ();
                }
                pending.push_back (i);
        }
 
        if (!pending.empty()) {
-               images.push_back (render_line (pending, fonts, target, time, frame_rate));
+               images.push_back(render_line(pending, target, time, frame_rate));
        }
 
        return images;
 }
+
+
+float
+FontMetrics::height(StringText const& subtitle)
+{
+       return get(subtitle)->second.second;
+}
+
+
+float
+FontMetrics::baseline_to_bottom(StringText const& subtitle)
+{
+       return get(subtitle)->second.first;
+}
+
+
+FontMetrics::Cache::iterator
+FontMetrics::get(StringText const& subtitle)
+{
+       auto id = Identifier(subtitle);
+
+       auto iter = _cache.find(id);
+       if (iter != _cache.end()) {
+               return iter;
+       }
+
+       auto const font_name = setup_font(subtitle.font);
+       auto layout = create_layout();
+       auto copy = subtitle;
+       copy.set_text("Qypjg");
+       setup_layout(layout, font_name, marked_up({copy}, _target_height, 1, font_name));
+       auto ink = layout->get_ink_extents();
+       auto const scale = float(_target_height * Pango::SCALE);
+       return _cache.insert({id, { ink.get_y() / scale, ink.get_height() / scale}}).first;
+}
+
+
+FontMetrics::Identifier::Identifier(StringText const& subtitle)
+       : font(subtitle.font)
+       , size(subtitle.size())
+       , aspect_adjust(subtitle.aspect_adjust())
+{
+
+}
+
+
+bool
+FontMetrics::Identifier::operator<(FontMetrics::Identifier const& other) const
+{
+       if (font != other.font) {
+               return font < other.font;
+       }
+
+       if (size != other.size) {
+           return size < other.size;
+       }
+
+       return aspect_adjust < other.aspect_adjust;
+}
+