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diff --git a/gfx/thebes/gfxFT2FontBase.cpp b/gfx/thebes/gfxFT2FontBase.cpp
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+/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "gfxFT2FontBase.h"
+#include "gfxFT2Utils.h"
+#include "harfbuzz/hb.h"
+#include "mozilla/Likely.h"
+#include "gfxFontConstants.h"
+#include "gfxFontUtils.h"
+
+using namespace mozilla::gfx;
+
+gfxFT2FontBase::gfxFT2FontBase(cairo_scaled_font_t *aScaledFont,
+ gfxFontEntry *aFontEntry,
+ const gfxFontStyle *aFontStyle)
+ : gfxFont(aFontEntry, aFontStyle, kAntialiasDefault, aScaledFont),
+ mSpaceGlyph(0),
+ mHasMetrics(false)
+{
+ cairo_scaled_font_reference(mScaledFont);
+ gfxFT2LockedFace face(this);
+ mFUnitsConvFactor = face.XScale();
+}
+
+gfxFT2FontBase::~gfxFT2FontBase()
+{
+ cairo_scaled_font_destroy(mScaledFont);
+}
+
+uint32_t
+gfxFT2FontBase::GetGlyph(uint32_t aCharCode)
+{
+ // FcFreeTypeCharIndex needs to lock the FT_Face and can end up searching
+ // through all the postscript glyph names in the font. Therefore use a
+ // lightweight cache, which is stored on the cairo_font_face_t.
+
+ cairo_font_face_t *face =
+ cairo_scaled_font_get_font_face(CairoScaledFont());
+
+ if (cairo_font_face_status(face) != CAIRO_STATUS_SUCCESS)
+ return 0;
+
+ // This cache algorithm and size is based on what is done in
+ // cairo_scaled_font_text_to_glyphs and pango_fc_font_real_get_glyph. I
+ // think the concept is that adjacent characters probably come mostly from
+ // one Unicode block. This assumption is probably not so valid with
+ // scripts with large character sets as used for East Asian languages.
+
+ struct CmapCacheSlot {
+ uint32_t mCharCode;
+ uint32_t mGlyphIndex;
+ };
+ const uint32_t kNumSlots = 256;
+ static cairo_user_data_key_t sCmapCacheKey;
+
+ CmapCacheSlot *slots = static_cast<CmapCacheSlot*>
+ (cairo_font_face_get_user_data(face, &sCmapCacheKey));
+
+ if (!slots) {
+ // cairo's caches can keep some cairo_font_faces alive past our last
+ // destroy, so the destroy function (free) for the cache must be
+ // callable from cairo without any assumptions about what other
+ // modules have not been shutdown.
+ slots = static_cast<CmapCacheSlot*>
+ (calloc(kNumSlots, sizeof(CmapCacheSlot)));
+ if (!slots)
+ return 0;
+
+ cairo_status_t status =
+ cairo_font_face_set_user_data(face, &sCmapCacheKey, slots, free);
+ if (status != CAIRO_STATUS_SUCCESS) { // OOM
+ free(slots);
+ return 0;
+ }
+
+ // Invalidate slot 0 by setting its char code to something that would
+ // never end up in slot 0. All other slots are already invalid
+ // because they have mCharCode = 0 and a glyph for char code 0 will
+ // always be in the slot 0.
+ slots[0].mCharCode = 1;
+ }
+
+ CmapCacheSlot *slot = &slots[aCharCode % kNumSlots];
+ if (slot->mCharCode != aCharCode) {
+ slot->mCharCode = aCharCode;
+ slot->mGlyphIndex = gfxFT2LockedFace(this).GetGlyph(aCharCode);
+ }
+
+ return slot->mGlyphIndex;
+}
+
+void
+gfxFT2FontBase::GetGlyphExtents(uint32_t aGlyph, cairo_text_extents_t* aExtents)
+{
+ NS_PRECONDITION(aExtents != nullptr, "aExtents must not be NULL");
+
+ cairo_glyph_t glyphs[1];
+ glyphs[0].index = aGlyph;
+ glyphs[0].x = 0.0;
+ glyphs[0].y = 0.0;
+ // cairo does some caching for us here but perhaps a small gain could be
+ // made by caching more. It is usually only the advance that is needed,
+ // so caching only the advance could allow many requests to be cached with
+ // little memory use. Ideally this cache would be merged with
+ // gfxGlyphExtents.
+ cairo_scaled_font_glyph_extents(CairoScaledFont(), glyphs, 1, aExtents);
+}
+
+const gfxFont::Metrics&
+gfxFT2FontBase::GetHorizontalMetrics()
+{
+ if (mHasMetrics)
+ return mMetrics;
+
+ if (MOZ_UNLIKELY(GetStyle()->size <= 0.0) ||
+ MOZ_UNLIKELY(GetStyle()->sizeAdjust == 0.0)) {
+ new(&mMetrics) gfxFont::Metrics(); // zero initialize
+ mSpaceGlyph = GetGlyph(' ');
+ } else {
+ gfxFT2LockedFace face(this);
+ face.GetMetrics(&mMetrics, &mSpaceGlyph);
+ }
+
+ SanitizeMetrics(&mMetrics, false);
+
+#if 0
+ // printf("font name: %s %f\n", NS_ConvertUTF16toUTF8(GetName()).get(), GetStyle()->size);
+ // printf ("pango font %s\n", pango_font_description_to_string (pango_font_describe (font)));
+
+ fprintf (stderr, "Font: %s\n", NS_ConvertUTF16toUTF8(GetName()).get());
+ fprintf (stderr, " emHeight: %f emAscent: %f emDescent: %f\n", mMetrics.emHeight, mMetrics.emAscent, mMetrics.emDescent);
+ fprintf (stderr, " maxAscent: %f maxDescent: %f\n", mMetrics.maxAscent, mMetrics.maxDescent);
+ fprintf (stderr, " internalLeading: %f externalLeading: %f\n", mMetrics.externalLeading, mMetrics.internalLeading);
+ fprintf (stderr, " spaceWidth: %f aveCharWidth: %f xHeight: %f\n", mMetrics.spaceWidth, mMetrics.aveCharWidth, mMetrics.xHeight);
+ fprintf (stderr, " uOff: %f uSize: %f stOff: %f stSize: %f\n", mMetrics.underlineOffset, mMetrics.underlineSize, mMetrics.strikeoutOffset, mMetrics.strikeoutSize);
+#endif
+
+ mHasMetrics = true;
+ return mMetrics;
+}
+
+// Get the glyphID of a space
+uint32_t
+gfxFT2FontBase::GetSpaceGlyph()
+{
+ GetHorizontalMetrics();
+ return mSpaceGlyph;
+}
+
+uint32_t
+gfxFT2FontBase::GetGlyph(uint32_t unicode, uint32_t variation_selector)
+{
+ if (variation_selector) {
+ uint32_t id =
+ gfxFT2LockedFace(this).GetUVSGlyph(unicode, variation_selector);
+ if (id) {
+ return id;
+ }
+ unicode = gfxFontUtils::GetUVSFallback(unicode, variation_selector);
+ if (unicode) {
+ return GetGlyph(unicode);
+ }
+ return 0;
+ }
+
+ return GetGlyph(unicode);
+}
+
+int32_t
+gfxFT2FontBase::GetGlyphWidth(DrawTarget& aDrawTarget, uint16_t aGID)
+{
+ cairo_text_extents_t extents;
+ GetGlyphExtents(aGID, &extents);
+ // convert to 16.16 fixed point
+ return NS_lround(0x10000 * extents.x_advance);
+}
+
+bool
+gfxFT2FontBase::SetupCairoFont(DrawTarget* aDrawTarget)
+{
+ // The scaled font ctm is not relevant right here because
+ // cairo_set_scaled_font does not record the scaled font itself, but
+ // merely the font_face, font_matrix, font_options. The scaled_font used
+ // for the target can be different from the scaled_font passed to
+ // cairo_set_scaled_font. (Unfortunately we have measured only for an
+ // identity ctm.)
+ cairo_scaled_font_t *cairoFont = CairoScaledFont();
+
+ if (cairo_scaled_font_status(cairoFont) != CAIRO_STATUS_SUCCESS) {
+ // Don't cairo_set_scaled_font as that would propagate the error to
+ // the cairo_t, precluding any further drawing.
+ return false;
+ }
+ // Thoughts on which font_options to set on the context:
+ //
+ // cairoFont has been created for screen rendering.
+ //
+ // When the context is being used for screen rendering, we should set
+ // font_options such that the same scaled_font gets used (when the ctm is
+ // the same). The use of explicit font_options recorded in
+ // CreateScaledFont ensures that this will happen.
+ //
+ // XXXkt: For pdf and ps surfaces, I don't know whether it's better to
+ // remove surface-specific options, or try to draw with the same
+ // scaled_font that was used to measure. As the same font_face is being
+ // used, its font_options will often override some values anyway (unless
+ // perhaps we remove those from the FcPattern at face creation).
+ //
+ // I can't see any significant difference in printing, irrespective of
+ // what is set here. It's too late to change things here as measuring has
+ // already taken place. We should really be measuring with a different
+ // font for pdf and ps surfaces (bug 403513).
+ cairo_set_scaled_font(gfxFont::RefCairo(aDrawTarget), cairoFont);
+ return true;
+}