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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 09:22:09 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 09:22:09 +0000
commit43a97878ce14b72f0981164f87f2e35e14151312 (patch)
tree620249daf56c0258faa40cbdcf9cfba06de2a846 /gfx/harfbuzz/src/OT/glyf/SimpleGlyph.hh
parentInitial commit. (diff)
downloadfirefox-43a97878ce14b72f0981164f87f2e35e14151312.tar.xz
firefox-43a97878ce14b72f0981164f87f2e35e14151312.zip
Adding upstream version 110.0.1.upstream/110.0.1upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'gfx/harfbuzz/src/OT/glyf/SimpleGlyph.hh')
-rw-r--r--gfx/harfbuzz/src/OT/glyf/SimpleGlyph.hh339
1 files changed, 339 insertions, 0 deletions
diff --git a/gfx/harfbuzz/src/OT/glyf/SimpleGlyph.hh b/gfx/harfbuzz/src/OT/glyf/SimpleGlyph.hh
new file mode 100644
index 0000000000..2b4aa99d25
--- /dev/null
+++ b/gfx/harfbuzz/src/OT/glyf/SimpleGlyph.hh
@@ -0,0 +1,339 @@
+#ifndef OT_GLYF_SIMPLEGLYPH_HH
+#define OT_GLYF_SIMPLEGLYPH_HH
+
+
+#include "../../hb-open-type.hh"
+
+
+namespace OT {
+namespace glyf_impl {
+
+
+struct SimpleGlyph
+{
+ enum simple_glyph_flag_t
+ {
+ FLAG_ON_CURVE = 0x01,
+ FLAG_X_SHORT = 0x02,
+ FLAG_Y_SHORT = 0x04,
+ FLAG_REPEAT = 0x08,
+ FLAG_X_SAME = 0x10,
+ FLAG_Y_SAME = 0x20,
+ FLAG_OVERLAP_SIMPLE = 0x40,
+ FLAG_RESERVED2 = 0x80
+ };
+
+ const GlyphHeader &header;
+ hb_bytes_t bytes;
+ SimpleGlyph (const GlyphHeader &header_, hb_bytes_t bytes_) :
+ header (header_), bytes (bytes_) {}
+
+ unsigned int instruction_len_offset () const
+ { return GlyphHeader::static_size + 2 * header.numberOfContours; }
+
+ unsigned int length (unsigned int instruction_len) const
+ { return instruction_len_offset () + 2 + instruction_len; }
+
+ unsigned int instructions_length () const
+ {
+ unsigned int instruction_length_offset = instruction_len_offset ();
+ if (unlikely (instruction_length_offset + 2 > bytes.length)) return 0;
+
+ const HBUINT16 &instructionLength = StructAtOffset<HBUINT16> (&bytes, instruction_length_offset);
+ /* Out of bounds of the current glyph */
+ if (unlikely (length (instructionLength) > bytes.length)) return 0;
+ return instructionLength;
+ }
+
+ const hb_bytes_t trim_padding () const
+ {
+ /* based on FontTools _g_l_y_f.py::trim */
+ const uint8_t *glyph = (uint8_t*) bytes.arrayZ;
+ const uint8_t *glyph_end = glyph + bytes.length;
+ /* simple glyph w/contours, possibly trimmable */
+ glyph += instruction_len_offset ();
+
+ if (unlikely (glyph + 2 >= glyph_end)) return hb_bytes_t ();
+ unsigned int num_coordinates = StructAtOffset<HBUINT16> (glyph - 2, 0) + 1;
+ unsigned int num_instructions = StructAtOffset<HBUINT16> (glyph, 0);
+
+ glyph += 2 + num_instructions;
+
+ unsigned int coord_bytes = 0;
+ unsigned int coords_with_flags = 0;
+ while (glyph < glyph_end)
+ {
+ uint8_t flag = *glyph;
+ glyph++;
+
+ unsigned int repeat = 1;
+ if (flag & FLAG_REPEAT)
+ {
+ if (unlikely (glyph >= glyph_end)) return hb_bytes_t ();
+ repeat = *glyph + 1;
+ glyph++;
+ }
+
+ unsigned int xBytes, yBytes;
+ xBytes = yBytes = 0;
+ if (flag & FLAG_X_SHORT) xBytes = 1;
+ else if ((flag & FLAG_X_SAME) == 0) xBytes = 2;
+
+ if (flag & FLAG_Y_SHORT) yBytes = 1;
+ else if ((flag & FLAG_Y_SAME) == 0) yBytes = 2;
+
+ coord_bytes += (xBytes + yBytes) * repeat;
+ coords_with_flags += repeat;
+ if (coords_with_flags >= num_coordinates) break;
+ }
+
+ if (unlikely (coords_with_flags != num_coordinates)) return hb_bytes_t ();
+ return bytes.sub_array (0, bytes.length + coord_bytes - (glyph_end - glyph));
+ }
+
+ /* zero instruction length */
+ void drop_hints ()
+ {
+ GlyphHeader &glyph_header = const_cast<GlyphHeader &> (header);
+ (HBUINT16 &) StructAtOffset<HBUINT16> (&glyph_header, instruction_len_offset ()) = 0;
+ }
+
+ void drop_hints_bytes (hb_bytes_t &dest_start, hb_bytes_t &dest_end) const
+ {
+ unsigned int instructions_len = instructions_length ();
+ unsigned int glyph_length = length (instructions_len);
+ dest_start = bytes.sub_array (0, glyph_length - instructions_len);
+ dest_end = bytes.sub_array (glyph_length, bytes.length - glyph_length);
+ }
+
+ void set_overlaps_flag ()
+ {
+ if (unlikely (!header.numberOfContours)) return;
+
+ unsigned flags_offset = length (instructions_length ());
+ if (unlikely (flags_offset + 1 > bytes.length)) return;
+
+ HBUINT8 &first_flag = (HBUINT8 &) StructAtOffset<HBUINT16> (&bytes, flags_offset);
+ first_flag = (uint8_t) first_flag | FLAG_OVERLAP_SIMPLE;
+ }
+
+ static bool read_flags (const HBUINT8 *&p /* IN/OUT */,
+ contour_point_vector_t &points_ /* IN/OUT */,
+ const HBUINT8 *end)
+ {
+ unsigned count = points_.length;
+ for (unsigned int i = 0; i < count;)
+ {
+ if (unlikely (p + 1 > end)) return false;
+ uint8_t flag = *p++;
+ points_.arrayZ[i++].flag = flag;
+ if (flag & FLAG_REPEAT)
+ {
+ if (unlikely (p + 1 > end)) return false;
+ unsigned int repeat_count = *p++;
+ unsigned stop = hb_min (i + repeat_count, count);
+ for (; i < stop; i++)
+ points_.arrayZ[i].flag = flag;
+ }
+ }
+ return true;
+ }
+
+ static bool read_points (const HBUINT8 *&p /* IN/OUT */,
+ contour_point_vector_t &points_ /* IN/OUT */,
+ const HBUINT8 *end,
+ float contour_point_t::*m,
+ const simple_glyph_flag_t short_flag,
+ const simple_glyph_flag_t same_flag)
+ {
+ int v = 0;
+
+ unsigned count = points_.length;
+ for (unsigned i = 0; i < count; i++)
+ {
+ unsigned flag = points_[i].flag;
+ if (flag & short_flag)
+ {
+ if (unlikely (p + 1 > end)) return false;
+ if (flag & same_flag)
+ v += *p++;
+ else
+ v -= *p++;
+ }
+ else
+ {
+ if (!(flag & same_flag))
+ {
+ if (unlikely (p + HBINT16::static_size > end)) return false;
+ v += *(const HBINT16 *) p;
+ p += HBINT16::static_size;
+ }
+ }
+ points_.arrayZ[i].*m = v;
+ }
+ return true;
+ }
+
+ bool get_contour_points (contour_point_vector_t &points_ /* OUT */,
+ bool phantom_only = false) const
+ {
+ const HBUINT16 *endPtsOfContours = &StructAfter<HBUINT16> (header);
+ int num_contours = header.numberOfContours;
+ assert (num_contours);
+ /* One extra item at the end, for the instruction-count below. */
+ if (unlikely (!bytes.check_range (&endPtsOfContours[num_contours]))) return false;
+ unsigned int num_points = endPtsOfContours[num_contours - 1] + 1;
+
+ points_.alloc (num_points + 4); // Allocate for phantom points, to avoid a possible copy
+ if (!points_.resize (num_points)) return false;
+ if (phantom_only) return true;
+
+ for (int i = 0; i < num_contours; i++)
+ points_[endPtsOfContours[i]].is_end_point = true;
+
+ /* Skip instructions */
+ const HBUINT8 *p = &StructAtOffset<HBUINT8> (&endPtsOfContours[num_contours + 1],
+ endPtsOfContours[num_contours]);
+
+ if (unlikely ((const char *) p < bytes.arrayZ)) return false; /* Unlikely overflow */
+ const HBUINT8 *end = (const HBUINT8 *) (bytes.arrayZ + bytes.length);
+ if (unlikely (p >= end)) return false;
+
+ /* Read x & y coordinates */
+ return read_flags (p, points_, end)
+ && read_points (p, points_, end, &contour_point_t::x,
+ FLAG_X_SHORT, FLAG_X_SAME)
+ && read_points (p, points_, end, &contour_point_t::y,
+ FLAG_Y_SHORT, FLAG_Y_SAME);
+ }
+
+ static void encode_coord (int value,
+ uint8_t &flag,
+ const simple_glyph_flag_t short_flag,
+ const simple_glyph_flag_t same_flag,
+ hb_vector_t<uint8_t> &coords /* OUT */)
+ {
+ if (value == 0)
+ {
+ flag |= same_flag;
+ }
+ else if (value >= -255 && value <= 255)
+ {
+ flag |= short_flag;
+ if (value > 0) flag |= same_flag;
+ else value = -value;
+
+ coords.arrayZ[coords.length++] = (uint8_t) value;
+ }
+ else
+ {
+ int16_t val = value;
+ coords.arrayZ[coords.length++] = val >> 8;
+ coords.arrayZ[coords.length++] = val & 0xff;
+ }
+ }
+
+ static void encode_flag (uint8_t &flag,
+ uint8_t &repeat,
+ uint8_t lastflag,
+ hb_vector_t<uint8_t> &flags /* OUT */)
+ {
+ if (flag == lastflag && repeat != 255)
+ {
+ repeat++;
+ if (repeat == 1)
+ {
+ /* We know there's room. */
+ flags.arrayZ[flags.length++] = flag;
+ }
+ else
+ {
+ unsigned len = flags.length;
+ flags.arrayZ[len-2] = flag | FLAG_REPEAT;
+ flags.arrayZ[len-1] = repeat;
+ }
+ }
+ else
+ {
+ repeat = 0;
+ flags.push (flag);
+ }
+ }
+
+ bool compile_bytes_with_deltas (const contour_point_vector_t &all_points,
+ bool no_hinting,
+ hb_bytes_t &dest_bytes /* OUT */)
+ {
+ if (header.numberOfContours == 0 || all_points.length <= 4)
+ {
+ dest_bytes = hb_bytes_t ();
+ return true;
+ }
+ unsigned num_points = all_points.length - 4;
+
+ hb_vector_t<uint8_t> flags, x_coords, y_coords;
+ if (unlikely (!flags.alloc (num_points))) return false;
+ if (unlikely (!x_coords.alloc (2*num_points))) return false;
+ if (unlikely (!y_coords.alloc (2*num_points))) return false;
+
+ uint8_t lastflag = 255, repeat = 0;
+ int prev_x = 0, prev_y = 0;
+
+ for (unsigned i = 0; i < num_points; i++)
+ {
+ uint8_t flag = all_points.arrayZ[i].flag;
+ flag &= FLAG_ON_CURVE + FLAG_OVERLAP_SIMPLE;
+
+ int cur_x = roundf (all_points.arrayZ[i].x);
+ int cur_y = roundf (all_points.arrayZ[i].y);
+ encode_coord (cur_x - prev_x, flag, FLAG_X_SHORT, FLAG_X_SAME, x_coords);
+ encode_coord (cur_y - prev_y, flag, FLAG_Y_SHORT, FLAG_Y_SAME, y_coords);
+ encode_flag (flag, repeat, lastflag, flags);
+
+ prev_x = cur_x;
+ prev_y = cur_y;
+ lastflag = flag;
+ }
+
+ unsigned len_before_instrs = 2 * header.numberOfContours + 2;
+ unsigned len_instrs = instructions_length ();
+ unsigned total_len = len_before_instrs + flags.length + x_coords.length + y_coords.length;
+
+ if (!no_hinting)
+ total_len += len_instrs;
+
+ char *p = (char *) hb_malloc (total_len);
+ if (unlikely (!p)) return false;
+
+ const char *src = bytes.arrayZ + GlyphHeader::static_size;
+ char *cur = p;
+ hb_memcpy (p, src, len_before_instrs);
+
+ cur += len_before_instrs;
+ src += len_before_instrs;
+
+ if (!no_hinting)
+ {
+ hb_memcpy (cur, src, len_instrs);
+ cur += len_instrs;
+ }
+
+ hb_memcpy (cur, flags.arrayZ, flags.length);
+ cur += flags.length;
+
+ hb_memcpy (cur, x_coords.arrayZ, x_coords.length);
+ cur += x_coords.length;
+
+ hb_memcpy (cur, y_coords.arrayZ, y_coords.length);
+
+ dest_bytes = hb_bytes_t (p, total_len);
+ return true;
+ }
+};
+
+
+} /* namespace glyf_impl */
+} /* namespace OT */
+
+
+#endif /* OT_GLYF_SIMPLEGLYPH_HH */