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6da7796cbe
C++ local var initialization always tricks me. Previously, Layout didn't have a constructor, which meant that defining it on the stack left mAdvance uninitialized. This was not an issue when we were doing "new Layout()", since that invokes zero-initialization, but was an issue for the skipCache path that was allocating layout on stack by just "Layout l" instead of "Layout l = Layout()". To avoid surprises, add a constructors that clears everything. Also adds reset() method to reset the layout for reuse. Change-Id: I3e02f00da9dd7d360abe13f63c310f6882292d0a
139 lines
4.2 KiB
C++
139 lines
4.2 KiB
C++
/*
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* Copyright (C) 2013 The Android Open Source Project
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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#ifndef MINIKIN_LAYOUT_H
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#define MINIKIN_LAYOUT_H
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#include <hb.h>
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#include <vector>
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#include <minikin/FontCollection.h>
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#include <minikin/MinikinFontFreeType.h>
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namespace android {
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// The Bitmap class is for debugging. We'll probably move it out
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// of here into a separate lightweight software rendering module
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// (optional, as we'd hope most clients would do their own)
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class Bitmap {
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public:
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Bitmap(int width, int height);
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~Bitmap();
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void writePnm(std::ofstream& o) const;
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void drawGlyph(const GlyphBitmap& bitmap, int x, int y);
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private:
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int width;
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int height;
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uint8_t* buf;
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};
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struct LayoutGlyph {
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// index into mFaces and mHbFonts vectors. We could imagine
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// moving this into a run length representation, because it's
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// more efficient for long strings, and we'll probably need
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// something like that for paint attributes (color, underline,
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// fake b/i, etc), as having those per-glyph is bloated.
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int font_ix;
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unsigned int glyph_id;
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float x;
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float y;
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};
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// Internal state used during layout operation
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class LayoutContext;
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// Lifecycle and threading assumptions for Layout:
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// The object is assumed to be owned by a single thread; multiple threads
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// may not mutate it at the same time.
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// The lifetime of the FontCollection set through setFontCollection must
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// extend through the lifetime of the Layout object.
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class Layout {
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public:
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Layout() : mGlyphs(), mAdvances(), mCollection(0), mFaces(), mAdvance(0), mBounds() {
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mBounds.setEmpty();
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}
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// Clears layout, ready to be used again
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void reset();
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void dump() const;
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void setFontCollection(const FontCollection* collection);
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void doLayout(const uint16_t* buf, size_t start, size_t count, size_t bufSize,
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int bidiFlags, const FontStyle &style, const MinikinPaint &paint);
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void draw(Bitmap*, int x0, int y0, float size) const;
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// Deprecated. Nont needed. Remove when callers are removed.
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static void init();
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// public accessors
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size_t nGlyphs() const;
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// Does not bump reference; ownership is still layout
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MinikinFont *getFont(int i) const;
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FontFakery getFakery(int i) const;
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unsigned int getGlyphId(int i) const;
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float getX(int i) const;
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float getY(int i) const;
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float getAdvance() const;
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// Get advances, copying into caller-provided buffer. The size of this
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// buffer must match the length of the string (nchars arg to doLayout).
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void getAdvances(float* advances);
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void getBounds(MinikinRect* rect);
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// Purge all caches, useful in low memory conditions
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static void purgeCaches();
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private:
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friend class LayoutCacheKey;
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// Find a face in the mFaces vector, or create a new entry
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int findFace(FakedFont face, LayoutContext* ctx);
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// Lay out a single bidi run
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void doLayoutRunCached(const uint16_t* buf, size_t start, size_t count, size_t bufSize,
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bool isRtl, LayoutContext* ctx, size_t dstStart);
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// Lay out a single word
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void doLayoutWord(const uint16_t* buf, size_t start, size_t count, size_t bufSize,
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bool isRtl, LayoutContext* ctx, size_t bufStart);
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// Lay out a single bidi run
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void doLayoutRun(const uint16_t* buf, size_t start, size_t count, size_t bufSize,
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bool isRtl, LayoutContext* ctx);
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// Append another layout (for example, cached value) into this one
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void appendLayout(Layout* src, size_t start);
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std::vector<LayoutGlyph> mGlyphs;
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std::vector<float> mAdvances;
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const FontCollection* mCollection;
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std::vector<FakedFont> mFaces;
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float mAdvance;
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MinikinRect mBounds;
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};
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} // namespace android
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#endif // MINIKIN_LAYOUT_H
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