Revive dump-emoji
diff --git a/src/dump-emoji.cc b/src/dump-emoji.cc
new file mode 100644
index 0000000..e3cabc7
--- /dev/null
+++ b/src/dump-emoji.cc
@@ -0,0 +1,322 @@
+/*
+ * Copyright © 2018  Ebrahim Byagowi
+ * Copyright © 2018  Khaled Hosny
+ *
+ *  This is part of HarfBuzz, a text shaping library.
+ *
+ * Permission is hereby granted, without written agreement and without
+ * license or royalty fees, to use, copy, modify, and distribute this
+ * software and its documentation for any purpose, provided that the
+ * above copyright notice and the following two paragraphs appear in
+ * all copies of this software.
+ *
+ * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
+ * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
+ * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
+ * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
+ * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
+ * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
+ * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
+ */
+
+#include "hb-static.cc"
+#include "hb-ot-color-cbdt-table.hh"
+#include "hb-ot-color-colr-table.hh"
+#include "hb-ot-color-cpal-table.hh"
+#include "hb-ot-color-sbix-table.hh"
+#include "hb-ot-color-svg-table.hh"
+
+#include "hb-ft.h"
+
+#include <ft2build.h>
+#include FT_FREETYPE_H
+#include FT_GLYPH_H
+
+#include <cairo.h>
+#include <cairo-ft.h>
+#include <cairo-svg.h>
+
+#ifdef HAVE_GLIB
+#include <glib.h>
+#endif
+#include <stdlib.h>
+#include <stdio.h>
+
+static void
+cbdt_callback (const uint8_t* data, unsigned int length,
+	       unsigned int group, unsigned int gid)
+{
+  char output_path[255];
+  sprintf (output_path, "out/cbdt-%d-%d.png", group, gid);
+  FILE *f = fopen (output_path, "wb");
+  fwrite (data, 1, length, f);
+  fclose (f);
+}
+
+static void
+sbix_dump (hb_face_t *face)
+{
+  OT::sbix::accelerator_t sbix;
+  sbix.init (face);
+  unsigned int length = 0;
+  unsigned int *available_ppems = sbix.get_available_ppems (&length);
+  unsigned int num_glyphs = face->num_glyphs;
+  for (unsigned int group = 0; group < length; group++)
+    for (unsigned int glyph_id = 0; glyph_id < num_glyphs; glyph_id++)
+    {
+      hb_blob_t *blob;
+      unsigned int ppem = available_ppems[group];
+      blob = sbix.reference_blob_for_glyph (glyph_id, ppem, ppem,
+					    HB_TAG('p','n','g',' '), nullptr, nullptr);
+      if (hb_blob_get_length (blob) == 0) continue;
+
+      char output_path[255];
+      sprintf (output_path, "out/sbix-%d-%d.png", ppem, glyph_id);
+      FILE *f = fopen (output_path, "wb");
+      unsigned int length;
+      const char* data = hb_blob_get_data (blob, &length);
+      fwrite (data, 1, length, f);
+      fclose (f);
+    }
+  sbix.fini ();
+}
+
+static void
+svg_dump (hb_face_t *face)
+{
+  unsigned glyph_count = hb_face_get_glyph_count (face);
+
+  OT::SVG::accelerator_t svg;
+  svg.init (face);
+
+  for (unsigned int glyph_id = 0; glyph_id < glyph_count; glyph_id++)
+  {
+    hb_blob_t *blob = svg.reference_blob_for_glyph (glyph_id);
+
+    if (hb_blob_get_length (blob) == 0) continue;
+
+    unsigned int length;
+    const char *data = hb_blob_get_data (blob, &length);
+
+    char output_path[256];
+    sprintf (output_path, "out/svg-%d.svg%s",
+	     glyph_id,
+	     // append "z" if the content is gzipped, https://stackoverflow.com/a/6059405
+	     (length > 2 && (data[0] == '\x1F') && (data[1] == '\x8B')) ? "z" : "");
+
+    FILE *f = fopen (output_path, "wb");
+    fwrite (data, 1, length, f);
+    fclose (f);
+
+    hb_blob_destroy (blob);
+  }
+
+  svg.fini ();
+}
+
+static void
+colr_cpal_dump (hb_face_t *face, cairo_font_face_t *cairo_face)
+{
+  unsigned int upem = hb_face_get_upem (face);
+
+  unsigned glyph_count = hb_face_get_glyph_count (face);
+  for (hb_codepoint_t gid = 0; gid < glyph_count; ++gid)
+  {
+    unsigned int num_layers = hb_ot_color_glyph_get_layers (face, gid, 0, nullptr, nullptr);
+    if (!num_layers)
+      continue;
+
+    hb_ot_color_layer_t *layers = (hb_ot_color_layer_t*) malloc (num_layers * sizeof (hb_ot_color_layer_t));
+
+    hb_ot_color_glyph_get_layers (face, gid, 0, &num_layers, layers);
+    if (num_layers)
+    {
+      // Measure
+      cairo_text_extents_t extents;
+      {
+	cairo_surface_t *surface = cairo_image_surface_create (CAIRO_FORMAT_ARGB32, 1, 1);
+	cairo_t *cr = cairo_create (surface);
+	cairo_set_font_face (cr, cairo_face);
+	cairo_set_font_size (cr, upem);
+
+	cairo_glyph_t *glyphs = (cairo_glyph_t *) calloc (num_layers, sizeof (cairo_glyph_t));
+	for (unsigned int j = 0; j < num_layers; ++j)
+	  glyphs[j].index = layers[j].glyph;
+	cairo_glyph_extents (cr, glyphs, num_layers, &extents);
+	free (glyphs);
+	cairo_surface_destroy (surface);
+	cairo_destroy (cr);
+      }
+
+      // Add a slight margin
+      extents.width += extents.width / 10;
+      extents.height += extents.height / 10;
+      extents.x_bearing -= extents.width / 20;
+      extents.y_bearing -= extents.height / 20;
+
+      // Render
+      unsigned int palette_count = hb_ot_color_palette_get_count (face);
+      for (unsigned int palette = 0; palette < palette_count; palette++) {
+	char output_path[255];
+
+	unsigned int num_colors = hb_ot_color_palette_get_colors (face, palette, 0, nullptr, nullptr);
+	if (!num_colors)
+	  continue;
+
+	hb_color_t *colors = (hb_color_t*) calloc (num_colors, sizeof (hb_color_t));
+	hb_ot_color_palette_get_colors (face, palette, 0, &num_colors, colors);
+	if (num_colors)
+	{
+	  // If we have more than one palette, use a simpler naming
+	  if (palette_count == 1)
+	    sprintf (output_path, "out/colr-%d.svg", gid);
+	  else
+	    sprintf (output_path, "out/colr-%d-%d.svg", gid, palette);
+
+	  cairo_surface_t *surface = cairo_svg_surface_create (output_path, extents.width, extents.height);
+	  cairo_t *cr = cairo_create (surface);
+	  cairo_set_font_face (cr, cairo_face);
+	  cairo_set_font_size (cr, upem);
+
+	  for (unsigned int layer = 0; layer < num_layers; ++layer)
+	  {
+	    hb_color_t color = 0x000000FF;
+	    if (layers[layer].color_index != 0xFFFF)
+	      color = colors[layers[layer].color_index];
+	    cairo_set_source_rgba (cr,
+				   hb_color_get_red (color) / 255.,
+				   hb_color_get_green (color) / 255.,
+				   hb_color_get_blue (color) / 255.,
+				   hb_color_get_alpha (color) / 255.);
+
+	    cairo_glyph_t glyph;
+	    glyph.index = layers[layer].glyph;
+	    glyph.x = -extents.x_bearing;
+	    glyph.y = -extents.y_bearing;
+	    cairo_show_glyphs (cr, &glyph, 1);
+	  }
+
+	  cairo_surface_destroy (surface);
+	  cairo_destroy (cr);
+	}
+	free (colors);
+      }
+    }
+
+    free (layers);
+  }
+}
+
+static void
+dump_glyphs (cairo_font_face_t *cairo_face, unsigned int upem,
+	     unsigned int num_glyphs)
+{
+  // Dump every glyph available on the font
+  return; // disabled for now
+  for (unsigned int i = 0; i < num_glyphs; ++i)
+  {
+    cairo_text_extents_t extents;
+    cairo_glyph_t glyph = {0};
+    glyph.index = i;
+
+    // Measure
+    {
+      cairo_surface_t *surface = cairo_image_surface_create (CAIRO_FORMAT_ARGB32, 1, 1);
+      cairo_t *cr = cairo_create (surface);
+      cairo_set_font_face (cr, cairo_face);
+      cairo_set_font_size (cr, upem);
+
+      cairo_glyph_extents (cr, &glyph, 1, &extents);
+      cairo_surface_destroy (surface);
+      cairo_destroy (cr);
+    }
+
+    // Add a slight margin
+    extents.width += extents.width / 10;
+    extents.height += extents.height / 10;
+    extents.x_bearing -= extents.width / 20;
+    extents.y_bearing -= extents.height / 20;
+
+    // Render
+    {
+      char output_path[255];
+      sprintf (output_path, "out/%d.svg", i);
+      cairo_surface_t *surface = cairo_svg_surface_create (output_path, extents.width, extents.height);
+      cairo_t *cr = cairo_create (surface);
+      cairo_set_font_face (cr, cairo_face);
+      cairo_set_font_size (cr, upem);
+      glyph.x = -extents.x_bearing;
+      glyph.y = -extents.y_bearing;
+      cairo_show_glyphs (cr, &glyph, 1);
+      cairo_surface_destroy (surface);
+      cairo_destroy (cr);
+    }
+  }
+}
+
+int
+main (int argc, char **argv)
+{
+  if (argc != 2) {
+    fprintf (stderr, "usage: %s font-file.ttf\n"
+		     "run it like `rm -rf out && mkdir out && %s font-file.ttf`\n",
+		     argv[0], argv[0]);
+    exit (1);
+  }
+
+
+  FILE *font_name_file = fopen ("out/_font_name_file.txt", "r");
+  if (font_name_file != nullptr)
+  {
+    fprintf (stderr, "Purge or move ./out folder in order to run a new dump\n");
+    exit (1);
+  }
+
+  font_name_file = fopen ("out/_font_name_file.txt", "w");
+  if (font_name_file == nullptr)
+  {
+    fprintf (stderr, "./out is not accessible as a folder, create it please\n");
+    exit (1);
+  }
+  fwrite (argv[1], 1, strlen (argv[1]), font_name_file);
+  fclose (font_name_file);
+
+  hb_blob_t *blob = hb_blob_create_from_file (argv[1]);
+  hb_face_t *face = hb_face_create (blob, 0);
+  hb_font_t *font = hb_font_create (face);
+
+  OT::CBDT::accelerator_t cbdt;
+  cbdt.init (face);
+  cbdt.dump (cbdt_callback);
+  cbdt.fini ();
+
+  sbix_dump (face);
+
+  if (hb_ot_color_has_svg (face))
+    svg_dump (face);
+
+  cairo_font_face_t *cairo_face;
+  {
+    FT_Library library;
+    FT_Init_FreeType (&library);
+    FT_Face ftface;
+    FT_New_Face (library, argv[1], 0, &ftface);
+    cairo_face = cairo_ft_font_face_create_for_ft_face (ftface, 0);
+  }
+  if (hb_ot_color_has_layers (face) && hb_ot_color_has_palettes (face))
+    colr_cpal_dump (face, cairo_face);
+
+  unsigned int num_glyphs = hb_face_get_glyph_count (face);
+  unsigned int upem = hb_face_get_upem (face);
+  dump_glyphs (cairo_face, upem, num_glyphs);
+
+  hb_font_destroy (font);
+  hb_face_destroy (face);
+  hb_blob_destroy (blob);
+
+  return 0;
+}