--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mupdf-source/thirdparty/harfbuzz/util/helper-cairo-user.hh	Mon Sep 15 11:43:07 2025 +0200
@@ -0,0 +1,316 @@
+/*
+ * Copyright © 2022  Google, Inc.
+ *
+ *  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.
+ *
+ * Google Author(s): Behdad Esfahbod
+ */
+
+#ifndef HELPER_CAIRO_USER_HH
+#define HELPER_CAIRO_USER_HH
+
+#include "font-options.hh"
+
+#include <cairo.h>
+#include <hb.h>
+
+#include "hb-blob.hh"
+
+static void
+move_to (hb_draw_funcs_t *dfuncs,
+	 cairo_t *cr,
+	 hb_draw_state_t *st,
+	 float to_x, float to_y,
+	 void *)
+{
+  cairo_move_to (cr,
+		 (double) to_x, (double) to_y);
+}
+
+static void
+line_to (hb_draw_funcs_t *dfuncs,
+	 cairo_t *cr,
+	 hb_draw_state_t *st,
+	 float to_x, float to_y,
+	 void *)
+{
+  cairo_line_to (cr,
+		 (double) to_x, (double) to_y);
+}
+
+static void
+cubic_to (hb_draw_funcs_t *dfuncs,
+	  cairo_t *cr,
+	  hb_draw_state_t *st,
+	  float control1_x, float control1_y,
+	  float control2_x, float control2_y,
+	  float to_x, float to_y,
+	  void *)
+{
+  cairo_curve_to (cr,
+		  (double) control1_x, (double) control1_y,
+		  (double) control2_x, (double) control2_y,
+		  (double) to_x, (double) to_y);
+}
+
+static void
+close_path (hb_draw_funcs_t *dfuncs,
+	    cairo_t *cr,
+	    hb_draw_state_t *st,
+	    void *)
+{
+  cairo_close_path (cr);
+}
+
+
+static hb_draw_funcs_t *
+get_cairo_draw_funcs ()
+{
+  static hb_draw_funcs_t *funcs;
+
+  if (!funcs)
+  {
+    funcs = hb_draw_funcs_create ();
+    hb_draw_funcs_set_move_to_func (funcs, (hb_draw_move_to_func_t) move_to, nullptr, nullptr);
+    hb_draw_funcs_set_line_to_func (funcs, (hb_draw_line_to_func_t) line_to, nullptr, nullptr);
+    hb_draw_funcs_set_cubic_to_func (funcs, (hb_draw_cubic_to_func_t) cubic_to, nullptr, nullptr);
+    hb_draw_funcs_set_close_path_func (funcs, (hb_draw_close_path_func_t) close_path, nullptr, nullptr);
+  }
+
+  return funcs;
+}
+
+static const cairo_user_data_key_t _hb_font_cairo_user_data_key = {0};
+
+static cairo_status_t
+render_glyph (cairo_scaled_font_t  *scaled_font,
+	      unsigned long         glyph,
+	      cairo_t              *cr,
+	      cairo_text_extents_t *extents)
+{
+  hb_font_t *font = (hb_font_t *) (cairo_font_face_get_user_data (cairo_scaled_font_get_font_face (scaled_font),
+								  &_hb_font_cairo_user_data_key));
+
+  hb_position_t x_scale, y_scale;
+  hb_font_get_scale (font, &x_scale, &y_scale);
+  cairo_scale (cr, +1./x_scale, -1./y_scale);
+
+  hb_font_get_glyph_shape (font, glyph, get_cairo_draw_funcs (), cr);
+  cairo_fill (cr);
+
+  return CAIRO_STATUS_SUCCESS;
+}
+
+#ifdef HAVE_CAIRO_USER_FONT_FACE_SET_RENDER_COLOR_GLYPH_FUNC
+
+#ifdef CAIRO_HAS_PNG_FUNCTIONS
+static inline cairo_status_t
+_hb_bytes_read_func (hb_bytes_t	*src,
+		     char	*data,
+		     unsigned	 length)
+{
+  if (unlikely (src->length < length))
+    return CAIRO_STATUS_READ_ERROR;
+
+  memcpy (data, src->arrayZ, length);
+  *src += length;
+
+  return CAIRO_STATUS_SUCCESS;
+}
+
+static cairo_status_t
+render_color_glyph_png (cairo_scaled_font_t  *scaled_font,
+			unsigned long         glyph,
+			cairo_t              *cr,
+			cairo_text_extents_t *extents)
+{
+  hb_font_t *font = (hb_font_t *) (cairo_font_face_get_user_data (cairo_scaled_font_get_font_face (scaled_font),
+								  &_hb_font_cairo_user_data_key));
+
+  hb_blob_t *blob = hb_ot_color_glyph_reference_png (font, glyph);
+  if (blob == hb_blob_get_empty ())
+    return CAIRO_STATUS_USER_FONT_NOT_IMPLEMENTED;
+
+  hb_position_t x_scale, y_scale;
+  hb_font_get_scale (font, &x_scale, &y_scale);
+  cairo_scale (cr, +1./x_scale, -1./y_scale);
+
+  /* Draw PNG. */
+  hb_bytes_t bytes = blob->as_bytes ();
+  cairo_surface_t *surface = cairo_image_surface_create_from_png_stream ((cairo_read_func_t) _hb_bytes_read_func,
+									 std::addressof (bytes));
+  hb_blob_destroy (blob);
+
+  if (unlikely (cairo_surface_status (surface)) != CAIRO_STATUS_SUCCESS)
+  {
+    cairo_surface_destroy (surface);
+    return CAIRO_STATUS_USER_FONT_NOT_IMPLEMENTED;
+  }
+
+  int width = cairo_image_surface_get_width (surface);
+  int height = cairo_image_surface_get_width (surface);
+
+  hb_glyph_extents_t hb_extents;
+  if (unlikely (!hb_font_get_glyph_extents (font, glyph, &hb_extents)))
+  {
+    cairo_surface_destroy (surface);
+    return CAIRO_STATUS_USER_FONT_NOT_IMPLEMENTED;
+  }
+
+  cairo_pattern_t *pattern = cairo_pattern_create_for_surface (surface);
+  cairo_pattern_set_extend (pattern, CAIRO_EXTEND_PAD);
+
+  cairo_matrix_t matrix = {(double) width, 0, 0, (double) height, 0, 0};
+  cairo_pattern_set_matrix (pattern, &matrix);
+
+  cairo_translate (cr, hb_extents.x_bearing, hb_extents.y_bearing);
+  cairo_scale (cr, hb_extents.width, hb_extents.height);
+  cairo_set_source (cr, pattern);
+
+  cairo_rectangle (cr, 0, 0, 1, 1);
+  cairo_fill (cr);
+  cairo_pattern_destroy (pattern);
+
+  cairo_surface_destroy (surface);
+  return CAIRO_STATUS_SUCCESS;
+}
+#endif
+
+static cairo_status_t
+render_color_glyph_layers (cairo_scaled_font_t  *scaled_font,
+			   unsigned long         glyph,
+			   cairo_t              *cr,
+			   cairo_text_extents_t *extents)
+{
+  hb_font_t *font = (hb_font_t *) (cairo_font_face_get_user_data (cairo_scaled_font_get_font_face (scaled_font),
+								  &_hb_font_cairo_user_data_key));
+  hb_face_t *face = hb_font_get_face (font);
+
+  unsigned count = hb_ot_color_glyph_get_layers (face, glyph, 0, nullptr, nullptr);
+  if (!count)
+    return CAIRO_STATUS_USER_FONT_NOT_IMPLEMENTED;
+
+  hb_ot_color_layer_t layers[16];
+  unsigned offset = 0, len;
+  do {
+    len = ARRAY_LENGTH (layers);
+    hb_ot_color_glyph_get_layers (face, glyph,
+				  offset,
+				  &len,
+				  layers);
+    for (unsigned i = 0; i < len; i++)
+    {
+      hb_color_t color;
+      unsigned clen = 1;
+      unsigned color_index = layers[i].color_index;
+      bool is_foreground = color_index == 65535;
+
+      if (!is_foreground)
+      {
+	hb_ot_color_palette_get_colors (face,
+					0/*palette_index*/,
+					color_index/*start_offset*/,
+					&clen/*color_count*/,
+					&color);
+	if (clen < 1)
+	  continue;
+      }
+
+      cairo_save (cr);
+      {
+	if (!is_foreground)
+	  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_status_t ret = render_glyph (scaled_font, layers[i].glyph, cr, extents);
+	if (ret != CAIRO_STATUS_SUCCESS)
+	  return ret;
+      }
+      cairo_restore (cr);
+    }
+  }
+  while (len == ARRAY_LENGTH (layers));
+  return CAIRO_STATUS_SUCCESS;
+}
+
+static cairo_status_t
+render_color_glyph (cairo_scaled_font_t  *scaled_font,
+		    unsigned long         glyph,
+		    cairo_t              *cr,
+		    cairo_text_extents_t *extents)
+{
+  cairo_status_t ret = CAIRO_STATUS_USER_FONT_NOT_IMPLEMENTED;
+
+#ifdef CAIRO_HAS_PNG_FUNCTIONS
+  ret = render_color_glyph_png (scaled_font, glyph, cr, extents);
+  if (ret != CAIRO_STATUS_USER_FONT_NOT_IMPLEMENTED)
+    return ret;
+#endif
+
+  ret = render_color_glyph_layers (scaled_font, glyph, cr, extents);
+  if (ret != CAIRO_STATUS_USER_FONT_NOT_IMPLEMENTED)
+    return ret;
+
+  return render_glyph (scaled_font, glyph, cr, extents);
+}
+
+#endif
+
+static inline cairo_font_face_t *
+helper_cairo_create_user_font_face (const font_options_t *font_opts)
+{
+  cairo_font_face_t *cairo_face = cairo_user_font_face_create ();
+
+  cairo_font_face_set_user_data (cairo_face,
+				 &_hb_font_cairo_user_data_key,
+				 hb_font_reference (font_opts->font),
+				 (cairo_destroy_func_t) hb_font_destroy);
+
+  cairo_user_font_face_set_render_glyph_func (cairo_face, render_glyph);
+#ifdef HAVE_CAIRO_USER_FONT_FACE_SET_RENDER_COLOR_GLYPH_FUNC
+  hb_face_t *face = hb_font_get_face (font_opts->font);
+  if (hb_ot_color_has_png (face) || hb_ot_color_has_layers (face))
+    cairo_user_font_face_set_render_color_glyph_func (cairo_face, render_color_glyph);
+#endif
+
+  return cairo_face;
+}
+
+static inline bool
+helper_cairo_user_font_face_has_data (cairo_font_face_t *font_face)
+{
+  return cairo_font_face_get_user_data (font_face, &_hb_font_cairo_user_data_key);
+}
+
+static inline bool
+helper_cairo_user_scaled_font_has_color (cairo_scaled_font_t *scaled_font)
+{
+  /* Ignoring SVG for now, since we cannot render it. */
+  hb_font_t *font = (hb_font_t *) (cairo_font_face_get_user_data (cairo_scaled_font_get_font_face (scaled_font),
+								  &_hb_font_cairo_user_data_key));
+  hb_face_t *face = hb_font_get_face (font);
+  return hb_ot_color_has_png (face) || hb_ot_color_has_layers (face);
+}
+
+#endif