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/*
* Copyright (c) 2022, Nico Weber <thakis@chromium.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <LibGfx/Font/TrueType/Cmap.h>
#include <LibTest/TestCase.h>
TEST_CASE(test_cmap_format_4)
{
// clang-format off
// Big endian.
u8 cmap_table[] =
{
// https://docs.microsoft.com/en-us/typography/opentype/spec/cmap#cmap-header
0, 0, // uint16 version
0, 1, // uint16 numTables
// https://docs.microsoft.com/en-us/typography/opentype/spec/cmap#encoding-records-and-encodings
0, 0, // uint16 platformID, 0 means "Unicode"
0, 3, // uint16 encodingID, 3 means "BMP only" for platformID==0.
0, 0, 0, 12, // Offset32 to encoding subtable.
// https://docs.microsoft.com/en-us/typography/opentype/spec/cmap#format-4-segment-mapping-to-delta-values
0, 4, // uint16 format = 4
0, 42, // uint16 length in bytes
0, 0, // uint16 language, must be 0
0, 6, // segCount * 2
0, 4, // searchRange
0, 1, // entrySelector
0, 2, // rangeShift
// endCode array, last entry must be 0xffff.
0, 128,
1, 0,
0xff, 0xff,
0, 0, // uint16 reservedPad
// startCode array
0, 16,
1, 0,
0xff, 0xff,
// delta array
0, 0,
0, 10,
0, 0,
// glyphID array
0, 0,
0, 0,
0, 0,
};
// clang-format on
auto cmap = TTF::Cmap::from_slice({ cmap_table, sizeof cmap_table }).value();
cmap.set_active_index(0);
// Format 4 can't handle code points > 0xffff.
// First range is 16..128.
EXPECT_EQ(cmap.glyph_id_for_code_point(15), 0u);
EXPECT_EQ(cmap.glyph_id_for_code_point(16), 16u);
EXPECT_EQ(cmap.glyph_id_for_code_point(128), 128u);
EXPECT_EQ(cmap.glyph_id_for_code_point(129), 0u);
// Second range is 256..256, with delta 10.
EXPECT_EQ(cmap.glyph_id_for_code_point(255), 0u);
EXPECT_EQ(cmap.glyph_id_for_code_point(256), 266u);
EXPECT_EQ(cmap.glyph_id_for_code_point(257), 0u);
// Third range is 0xffff..0xffff.
// From https://docs.microsoft.com/en-us/typography/opentype/spec/cmap#format-4-segment-mapping-to-delta-values:
// "the final start code and endCode values must be 0xFFFF. This segment need not contain any valid mappings.
// (It can just map the single character code 0xFFFF to missingGlyph). However, the segment must be present."
// FIXME: Make TTF::Cmap::from_slice() reject inputs where this isn't true.
EXPECT_EQ(cmap.glyph_id_for_code_point(0xfeff), 0u);
EXPECT_EQ(cmap.glyph_id_for_code_point(0xffff), 0xffffu);
EXPECT_EQ(cmap.glyph_id_for_code_point(0x1'0000), 0u);
}
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