Libraries: Move to Userland/Libraries/

1 files changed, 140 insertions, 0 deletions

diff --git a/Userland/Libraries/LibTTF/Font.h b/Userland/Libraries/LibTTF/Font.h
new file mode 100644
index 0000000000..79185411c0
--- /dev/null
+++ b/Userland/Libraries/LibTTF/Font.h
@@ -0,0 +1,140 @@
+/*
+ * 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/ByteBuffer.h>
+#include <AK/HashMap.h>
+#include <AK/Noncopyable.h>
+#include <AK/RefCounted.h>
+#include <AK/StringView.h>
+#include <LibGfx/Bitmap.h>
+#include <LibGfx/Size.h>
+#include <LibTTF/Cmap.h>
+#include <LibTTF/Glyf.h>
+#include <LibTTF/Tables.h>
+
+#define POINTS_PER_INCH 72.0f
+#define DEFAULT_DPI 96
+
+namespace TTF {
+
+struct ScaledFontMetrics {
+    int ascender;
+    int descender;
+    int line_gap;
+    int advance_width_max;
+
+    int height() const
+    {
+        return ascender - descender;
+    }
+};
+
+struct ScaledGlyphMetrics {
+    int ascender;
+    int descender;
+    int advance_width;
+    int left_side_bearing;
+};
+
+class Font : public RefCounted<Font> {
+    AK_MAKE_NONCOPYABLE(Font);
+
+public:
+    static RefPtr<Font> load_from_file(const StringView& path, unsigned index = 0);
+    static RefPtr<Font> load_from_memory(ByteBuffer&, unsigned index = 0);
+
+    ScaledFontMetrics metrics(float x_scale, float y_scale) const;
+    ScaledGlyphMetrics glyph_metrics(u32 glyph_id, float x_scale, float y_scale) const;
+    RefPtr<Gfx::Bitmap> raster_glyph(u32 glyph_id, float x_scale, float y_scale) const;
+    u32 glyph_count() const;
+    u16 units_per_em() const;
+    u32 glyph_id_for_codepoint(u32 codepoint) const { return m_cmap.glyph_id_for_codepoint(codepoint); }
+
+private:
+    enum class Offsets {
+        NumTables = 4,
+        TableRecord_Offset = 8,
+        TableRecord_Length = 12,
+    };
+    enum class Sizes {
+        TTCHeaderV1 = 12,
+        OffsetTable = 12,
+        TableRecord = 16,
+    };
+
+    static RefPtr<Font> load_from_offset(ByteBuffer&&, unsigned index = 0);
+    Font(ByteBuffer&& buffer, Head&& head, Hhea&& hhea, Maxp&& maxp, Hmtx&& hmtx, Cmap&& cmap, Loca&& loca, Glyf&& glyf)
+        : m_buffer(move(buffer))
+        , m_head(move(head))
+        , m_hhea(move(hhea))
+        , m_maxp(move(maxp))
+        , m_hmtx(move(hmtx))
+        , m_loca(move(loca))
+        , m_glyf(move(glyf))
+        , m_cmap(move(cmap))
+    {
+    }
+
+    // This owns the font data
+    ByteBuffer m_buffer;
+    // These are stateful wrappers around non-owning slices
+    Head m_head;
+    Hhea m_hhea;
+    Maxp m_maxp;
+    Hmtx m_hmtx;
+    Loca m_loca;
+    Glyf m_glyf;
+    Cmap m_cmap;
+};
+
+class ScaledFont {
+public:
+    ScaledFont(RefPtr<Font> font, float point_width, float point_height, unsigned dpi_x = DEFAULT_DPI, unsigned dpi_y = DEFAULT_DPI)
+        : m_font(font)
+    {
+        float units_per_em = m_font->units_per_em();
+        m_x_scale = (point_width * dpi_x) / (POINTS_PER_INCH * units_per_em);
+        m_y_scale = (point_height * dpi_y) / (POINTS_PER_INCH * units_per_em);
+    }
+    u32 glyph_id_for_codepoint(u32 codepoint) const { return m_font->glyph_id_for_codepoint(codepoint); }
+    ScaledFontMetrics metrics() const { return m_font->metrics(m_x_scale, m_y_scale); }
+    ScaledGlyphMetrics glyph_metrics(u32 glyph_id) const { return m_font->glyph_metrics(glyph_id, m_x_scale, m_y_scale); }
+    RefPtr<Gfx::Bitmap> raster_glyph(u32 glyph_id) const;
+    u32 glyph_count() const { return m_font->glyph_count(); }
+    int width(const StringView&) const;
+    int width(const Utf8View&) const;
+    int width(const Utf32View&) const;
+
+private:
+    RefPtr<Font> m_font;
+    float m_x_scale { 0.0 };
+    float m_y_scale { 0.0 };
+    mutable AK::HashMap<u32, RefPtr<Gfx::Bitmap>> m_cached_glyph_bitmaps;
+};
+
+}