diff options
Diffstat (limited to 'Build/source/texk/dvisvgm/dvisvgm-src/libs/woff2/src/transform.cc')
-rw-r--r-- | Build/source/texk/dvisvgm/dvisvgm-src/libs/woff2/src/transform.cc | 412 |
1 files changed, 0 insertions, 412 deletions
diff --git a/Build/source/texk/dvisvgm/dvisvgm-src/libs/woff2/src/transform.cc b/Build/source/texk/dvisvgm/dvisvgm-src/libs/woff2/src/transform.cc deleted file mode 100644 index 999bef37458..00000000000 --- a/Build/source/texk/dvisvgm/dvisvgm-src/libs/woff2/src/transform.cc +++ /dev/null @@ -1,412 +0,0 @@ -/* Copyright 2013 Google Inc. All Rights Reserved. - - Distributed under MIT license. - See file LICENSE for detail or copy at https://opensource.org/licenses/MIT -*/ - -/* Library for preprocessing fonts as part of the WOFF 2.0 conversion. */ - -#include "./transform.h" - -#include <complex> // for std::abs - -#include "./buffer.h" -#include "./font.h" -#include "./glyph.h" -#include "./table_tags.h" -#include "./variable_length.h" - -namespace woff2 { - -namespace { - -const int FLAG_ARG_1_AND_2_ARE_WORDS = 1 << 0; -const int FLAG_WE_HAVE_INSTRUCTIONS = 1 << 8; - -void WriteBytes(std::vector<uint8_t>* out, const uint8_t* data, size_t len) { - if (len == 0) return; - size_t offset = out->size(); - out->resize(offset + len); - memcpy(&(*out)[offset], data, len); -} - -void WriteBytes(std::vector<uint8_t>* out, const std::vector<uint8_t>& in) { - for (size_t i = 0; i < in.size(); ++i) { - out->push_back(in[i]); - } -} - -void WriteUShort(std::vector<uint8_t>* out, int value) { - out->push_back(value >> 8); - out->push_back(value & 255); -} - -void WriteLong(std::vector<uint8_t>* out, int value) { - out->push_back((value >> 24) & 255); - out->push_back((value >> 16) & 255); - out->push_back((value >> 8) & 255); - out->push_back(value & 255); -} - -// Glyf table preprocessing, based on -// GlyfEncoder.java -class GlyfEncoder { - public: - explicit GlyfEncoder(int num_glyphs) - : n_glyphs_(num_glyphs) { - bbox_bitmap_.resize(((num_glyphs + 31) >> 5) << 2); - } - - bool Encode(int glyph_id, const Glyph& glyph) { - if (glyph.composite_data_size > 0) { - WriteCompositeGlyph(glyph_id, glyph); - } else if (glyph.contours.size() > 0) { - WriteSimpleGlyph(glyph_id, glyph); - } else { - WriteUShort(&n_contour_stream_, 0); - } - return true; - } - - void GetTransformedGlyfBytes(std::vector<uint8_t>* result) { - WriteLong(result, 0); // version - WriteUShort(result, n_glyphs_); - WriteUShort(result, 0); // index_format, will be set later - WriteLong(result, n_contour_stream_.size()); - WriteLong(result, n_points_stream_.size()); - WriteLong(result, flag_byte_stream_.size()); - WriteLong(result, glyph_stream_.size()); - WriteLong(result, composite_stream_.size()); - WriteLong(result, bbox_bitmap_.size() + bbox_stream_.size()); - WriteLong(result, instruction_stream_.size()); - WriteBytes(result, n_contour_stream_); - WriteBytes(result, n_points_stream_); - WriteBytes(result, flag_byte_stream_); - WriteBytes(result, glyph_stream_); - WriteBytes(result, composite_stream_); - WriteBytes(result, bbox_bitmap_); - WriteBytes(result, bbox_stream_); - WriteBytes(result, instruction_stream_); - } - - private: - void WriteInstructions(const Glyph& glyph) { - Write255UShort(&glyph_stream_, glyph.instructions_size); - WriteBytes(&instruction_stream_, - glyph.instructions_data, glyph.instructions_size); - } - - bool ShouldWriteSimpleGlyphBbox(const Glyph& glyph) { - if (glyph.contours.empty() || glyph.contours[0].empty()) { - return glyph.x_min || glyph.y_min || glyph.x_max || glyph.y_max; - } - - int16_t x_min = glyph.contours[0][0].x; - int16_t y_min = glyph.contours[0][0].y; - int16_t x_max = x_min; - int16_t y_max = y_min; - for (const auto& contour : glyph.contours) { - for (const auto& point : contour) { - if (point.x < x_min) x_min = point.x; - if (point.x > x_max) x_max = point.x; - if (point.y < y_min) y_min = point.y; - if (point.y > y_max) y_max = point.y; - } - } - - if (glyph.x_min != x_min) - return true; - if (glyph.y_min != y_min) - return true; - if (glyph.x_max != x_max) - return true; - if (glyph.y_max != y_max) - return true; - - return false; - } - - void WriteSimpleGlyph(int glyph_id, const Glyph& glyph) { - int num_contours = glyph.contours.size(); - WriteUShort(&n_contour_stream_, num_contours); - if (ShouldWriteSimpleGlyphBbox(glyph)) { - WriteBbox(glyph_id, glyph); - } - for (int i = 0; i < num_contours; i++) { - Write255UShort(&n_points_stream_, glyph.contours[i].size()); - } - int lastX = 0; - int lastY = 0; - for (int i = 0; i < num_contours; i++) { - int num_points = glyph.contours[i].size(); - for (int j = 0; j < num_points; j++) { - int x = glyph.contours[i][j].x; - int y = glyph.contours[i][j].y; - int dx = x - lastX; - int dy = y - lastY; - WriteTriplet(glyph.contours[i][j].on_curve, dx, dy); - lastX = x; - lastY = y; - } - } - if (num_contours > 0) { - WriteInstructions(glyph); - } - } - - void WriteCompositeGlyph(int glyph_id, const Glyph& glyph) { - WriteUShort(&n_contour_stream_, -1); - WriteBbox(glyph_id, glyph); - WriteBytes(&composite_stream_, - glyph.composite_data, - glyph.composite_data_size); - if (glyph.have_instructions) { - WriteInstructions(glyph); - } - } - - void WriteBbox(int glyph_id, const Glyph& glyph) { - bbox_bitmap_[glyph_id >> 3] |= 0x80 >> (glyph_id & 7); - WriteUShort(&bbox_stream_, glyph.x_min); - WriteUShort(&bbox_stream_, glyph.y_min); - WriteUShort(&bbox_stream_, glyph.x_max); - WriteUShort(&bbox_stream_, glyph.y_max); - } - - void WriteTriplet(bool on_curve, int x, int y) { - int abs_x = std::abs(x); - int abs_y = std::abs(y); - int on_curve_bit = on_curve ? 0 : 128; - int x_sign_bit = (x < 0) ? 0 : 1; - int y_sign_bit = (y < 0) ? 0 : 1; - int xy_sign_bits = x_sign_bit + 2 * y_sign_bit; - if (x == 0 && abs_y < 1280) { - flag_byte_stream_.push_back(on_curve_bit + - ((abs_y & 0xf00) >> 7) + y_sign_bit); - glyph_stream_.push_back(abs_y & 0xff); - } else if (y == 0 && abs_x < 1280) { - flag_byte_stream_.push_back(on_curve_bit + 10 + - ((abs_x & 0xf00) >> 7) + x_sign_bit); - glyph_stream_.push_back(abs_x & 0xff); - } else if (abs_x < 65 && abs_y < 65) { - flag_byte_stream_.push_back(on_curve_bit + 20 + - ((abs_x - 1) & 0x30) + - (((abs_y - 1) & 0x30) >> 2) + - xy_sign_bits); - glyph_stream_.push_back((((abs_x - 1) & 0xf) << 4) | ((abs_y - 1) & 0xf)); - } else if (abs_x < 769 && abs_y < 769) { - flag_byte_stream_.push_back(on_curve_bit + 84 + - 12 * (((abs_x - 1) & 0x300) >> 8) + - (((abs_y - 1) & 0x300) >> 6) + xy_sign_bits); - glyph_stream_.push_back((abs_x - 1) & 0xff); - glyph_stream_.push_back((abs_y - 1) & 0xff); - } else if (abs_x < 4096 && abs_y < 4096) { - flag_byte_stream_.push_back(on_curve_bit + 120 + xy_sign_bits); - glyph_stream_.push_back(abs_x >> 4); - glyph_stream_.push_back(((abs_x & 0xf) << 4) | (abs_y >> 8)); - glyph_stream_.push_back(abs_y & 0xff); - } else { - flag_byte_stream_.push_back(on_curve_bit + 124 + xy_sign_bits); - glyph_stream_.push_back(abs_x >> 8); - glyph_stream_.push_back(abs_x & 0xff); - glyph_stream_.push_back(abs_y >> 8); - glyph_stream_.push_back(abs_y & 0xff); - } - } - - std::vector<uint8_t> n_contour_stream_; - std::vector<uint8_t> n_points_stream_; - std::vector<uint8_t> flag_byte_stream_; - std::vector<uint8_t> composite_stream_; - std::vector<uint8_t> bbox_bitmap_; - std::vector<uint8_t> bbox_stream_; - std::vector<uint8_t> glyph_stream_; - std::vector<uint8_t> instruction_stream_; - int n_glyphs_; -}; - -} // namespace - -bool TransformGlyfAndLocaTables(Font* font) { - // no transform for CFF - const Font::Table* glyf_table = font->FindTable(kGlyfTableTag); - const Font::Table* loca_table = font->FindTable(kLocaTableTag); - - // If you don't have glyf/loca this transform isn't very interesting - if (loca_table == NULL && glyf_table == NULL) { - return true; - } - // It would be best if you didn't have just one of glyf/loca - if ((glyf_table == NULL) != (loca_table == NULL)) { - return FONT_COMPRESSION_FAILURE(); - } - // Must share neither or both loca & glyf - if (loca_table->IsReused() != glyf_table->IsReused()) { - return FONT_COMPRESSION_FAILURE(); - } - if (loca_table->IsReused()) { - return true; - } - - Font::Table* transformed_glyf = &font->tables[kGlyfTableTag ^ 0x80808080]; - Font::Table* transformed_loca = &font->tables[kLocaTableTag ^ 0x80808080]; - - int num_glyphs = NumGlyphs(*font); - GlyfEncoder encoder(num_glyphs); - for (int i = 0; i < num_glyphs; ++i) { - Glyph glyph; - const uint8_t* glyph_data; - size_t glyph_size; - if (!GetGlyphData(*font, i, &glyph_data, &glyph_size) || - (glyph_size > 0 && !ReadGlyph(glyph_data, glyph_size, &glyph))) { - return FONT_COMPRESSION_FAILURE(); - } - encoder.Encode(i, glyph); - } - encoder.GetTransformedGlyfBytes(&transformed_glyf->buffer); - - const Font::Table* head_table = font->FindTable(kHeadTableTag); - if (head_table == NULL || head_table->length < 52) { - return FONT_COMPRESSION_FAILURE(); - } - transformed_glyf->buffer[7] = head_table->data[51]; // index_format - - transformed_glyf->tag = kGlyfTableTag ^ 0x80808080; - transformed_glyf->length = transformed_glyf->buffer.size(); - transformed_glyf->data = transformed_glyf->buffer.data(); - - transformed_loca->tag = kLocaTableTag ^ 0x80808080; - transformed_loca->length = 0; - transformed_loca->data = NULL; - - return true; -} - -// See https://www.microsoft.com/typography/otspec/hmtx.htm -// See WOFF2 spec, 5.4. Transformed hmtx table format -bool TransformHmtxTable(Font* font) { - const Font::Table* glyf_table = font->FindTable(kGlyfTableTag); - const Font::Table* hmtx_table = font->FindTable(kHmtxTableTag); - const Font::Table* hhea_table = font->FindTable(kHheaTableTag); - - // If you don't have hmtx or a glyf not much is going to happen here - if (hmtx_table == NULL || glyf_table == NULL) { - return true; - } - - // hmtx without hhea doesn't make sense - if (hhea_table == NULL) { - return FONT_COMPRESSION_FAILURE(); - } - - // Skip 34 to reach 'hhea' numberOfHMetrics - Buffer hhea_buf(hhea_table->data, hhea_table->length); - uint16_t num_hmetrics; - if (!hhea_buf.Skip(34) || !hhea_buf.ReadU16(&num_hmetrics)) { - return FONT_COMPRESSION_FAILURE(); - } - - // Must have at least one hMetric - if (num_hmetrics < 1) { - return FONT_COMPRESSION_FAILURE(); - } - - int num_glyphs = NumGlyphs(*font); - - // Most fonts can be transformed; assume it's a go until proven otherwise - std::vector<uint16_t> advance_widths; - std::vector<int16_t> proportional_lsbs; - std::vector<int16_t> monospace_lsbs; - - bool remove_proportional_lsb = true; - bool remove_monospace_lsb = (num_glyphs - num_hmetrics) > 0; - - Buffer hmtx_buf(hmtx_table->data, hmtx_table->length); - for (int i = 0; i < num_glyphs; i++) { - Glyph glyph; - const uint8_t* glyph_data; - size_t glyph_size; - if (!GetGlyphData(*font, i, &glyph_data, &glyph_size) || - (glyph_size > 0 && !ReadGlyph(glyph_data, glyph_size, &glyph))) { - return FONT_COMPRESSION_FAILURE(); - } - - uint16_t advance_width = 0; - int16_t lsb = 0; - - if (i < num_hmetrics) { - // [0, num_hmetrics) are proportional hMetrics - if (!hmtx_buf.ReadU16(&advance_width)) { - return FONT_COMPRESSION_FAILURE(); - } - - if (!hmtx_buf.ReadS16(&lsb)) { - return FONT_COMPRESSION_FAILURE(); - } - - if (glyph_size > 0 && glyph.x_min != lsb) { - remove_proportional_lsb = false; - } - - advance_widths.push_back(advance_width); - proportional_lsbs.push_back(lsb); - } else { - // [num_hmetrics, num_glyphs) are monospace leftSideBearing's - if (!hmtx_buf.ReadS16(&lsb)) { - return FONT_COMPRESSION_FAILURE(); - } - if (glyph_size > 0 && glyph.x_min != lsb) { - remove_monospace_lsb = false; - } - monospace_lsbs.push_back(lsb); - } - - // If we know we can't optimize, bail out completely - if (!remove_proportional_lsb && !remove_monospace_lsb) { - return true; - } - } - - Font::Table* transformed_hmtx = &font->tables[kHmtxTableTag ^ 0x80808080]; - - uint8_t flags = 0; - size_t transformed_size = 1 + 2 * advance_widths.size(); - if (remove_proportional_lsb) { - flags |= 1; - } else { - transformed_size += 2 * proportional_lsbs.size(); - } - if (remove_monospace_lsb) { - flags |= 1 << 1; - } else { - transformed_size += 2 * monospace_lsbs.size(); - } - - transformed_hmtx->buffer.reserve(transformed_size); - std::vector<uint8_t>* out = &transformed_hmtx->buffer; - WriteBytes(out, &flags, 1); - for (uint16_t advance_width : advance_widths) { - WriteUShort(out, advance_width); - } - - if (!remove_proportional_lsb) { - for (int16_t lsb : proportional_lsbs) { - WriteUShort(out, lsb); - } - } - if (!remove_monospace_lsb) { - for (int16_t lsb : monospace_lsbs) { - WriteUShort(out, lsb); - } - } - - transformed_hmtx->tag = kHmtxTableTag ^ 0x80808080; - transformed_hmtx->flag_byte = 1 << 6; - transformed_hmtx->length = transformed_hmtx->buffer.size(); - transformed_hmtx->data = transformed_hmtx->buffer.data(); - - - return true; -} - -} // namespace woff2 |