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diff --git a/Userland/Libraries/LibTTF/Cmap.h b/Userland/Libraries/LibTTF/Cmap.h
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+++ b/Userland/Libraries/LibTTF/Cmap.h
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+/*
+ * Copyright (c) 2020, Srimanta Barua <srimanta.barua1@gmail.com>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#pragma once
+
+#include <AK/Span.h>
+
+namespace TTF {
+
+class Cmap {
+public:
+    class Subtable {
+    public:
+        enum class Platform {
+            Unicode = 0,
+            Macintosh = 1,
+            Windows = 3,
+            Custom = 4,
+        };
+        enum class Format {
+            ByteEncoding = 0,
+            HighByte = 2,
+            SegmentToDelta = 4,
+            TrimmedTable = 6,
+            Mixed16And32 = 8,
+            TrimmedArray = 10,
+            SegmentedCoverage = 12,
+            ManyToOneRange = 13,
+            UnicodeVariationSequences = 14,
+        };
+        enum class WindowsEncoding {
+            UnicodeBMP = 1,
+            UnicodeFullRepertoire = 10,
+        };
+
+        Subtable(const ReadonlyBytes& slice, u16 platform_id, u16 encoding_id)
+            : m_slice(slice)
+            , m_raw_platform_id(platform_id)
+            , m_encoding_id(encoding_id)
+        {
+        }
+        // Returns 0 if glyph not found. This corresponds to the "missing glyph"
+        u32 glyph_id_for_codepoint(u32 codepoint) const;
+        Platform platform_id() const;
+        u16 encoding_id() const { return m_encoding_id; }
+        Format format() const;
+
+    private:
+        enum class Table4Offsets {
+            SegCountX2 = 6,
+            EndConstBase = 14,
+            StartConstBase = 16,
+            DeltaConstBase = 16,
+            RangeConstBase = 16,
+            GlyphOffsetConstBase = 16,
+        };
+        enum class Table4Sizes {
+            Constant = 16,
+            NonConstMultiplier = 4,
+        };
+        enum class Table12Offsets {
+            NumGroups = 12,
+            Record_StartCode = 16,
+            Record_EndCode = 20,
+            Record_StartGlyph = 24,
+        };
+        enum class Table12Sizes {
+            Header = 16,
+            Record = 12,
+        };
+
+        u32 glyph_id_for_codepoint_table_4(u32 codepoint) const;
+        u32 glyph_id_for_codepoint_table_12(u32 codepoint) const;
+
+        ReadonlyBytes m_slice;
+        u16 m_raw_platform_id { 0 };
+        u16 m_encoding_id { 0 };
+    };
+
+    static Optional<Cmap> from_slice(const ReadonlyBytes&);
+    u32 num_subtables() const;
+    Optional<Subtable> subtable(u32 index) const;
+    void set_active_index(u32 index) { m_active_index = index; }
+    // Returns 0 if glyph not found. This corresponds to the "missing glyph"
+    u32 glyph_id_for_codepoint(u32 codepoint) const;
+
+private:
+    enum class Offsets {
+        NumTables = 2,
+        EncodingRecord_EncodingID = 2,
+        EncodingRecord_Offset = 4,
+    };
+    enum class Sizes {
+        TableHeader = 4,
+        EncodingRecord = 8,
+    };
+
+    Cmap(const ReadonlyBytes& slice)
+        : m_slice(slice)
+    {
+    }
+
+    ReadonlyBytes m_slice;
+    u32 m_active_index { UINT32_MAX };
+};
+
+}