Slug.h

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/*
 * Copyright 2021 Google LLC
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */
 
#ifndef sktext_gpu_Slug_DEFINED
#define sktext_gpu_Slug_DEFINED
 
#include "include/core/SkRect.h"
#include "include/core/SkRefCnt.h"
#include "include/private/base/SkAPI.h"
 
#include <cstddef>
#include <cstdint>
 
class SkCanvas;
class SkData;
class SkPaint;
class SkReadBuffer;
class SkStrikeClient;
class SkTextBlob;
class SkWriteBuffer;
struct SkDeserialProcs;
struct SkPoint;
 
namespace sktext::gpu {
// Slug encapsulates an SkTextBlob at a specific origin, using a specific paint. It can be
// manipulated using matrix and clip changes to the canvas. If the canvas is transformed, then
// the Slug will also transform with smaller glyphs using bi-linear interpolation to render. You
// can think of a Slug as making a rubber stamp out of a SkTextBlob.
class SK_API Slug : public SkRefCnt {
public:
    // Return nullptr if the blob would not draw. This is not because of clipping, but because of
    // some paint optimization. The Slug is captured as if drawn using drawTextBlob.
    static sk_sp<Slug> ConvertBlob(
            SkCanvas* canvas, const SkTextBlob& blob, SkPoint origin, const SkPaint& paint);
 
    // Serialize the slug.
    sk_sp<SkData> serialize() const;
    size_t serialize(void* buffer, size_t size) const;
 
    // Set the client parameter to the appropriate SkStrikeClient when typeface ID translation
    // is needed.
    static sk_sp<Slug> Deserialize(const void* data,
                                   size_t size,
                                   const SkStrikeClient* client = nullptr);
    static sk_sp<Slug> MakeFromBuffer(SkReadBuffer& buffer);
 
    // Allows clients to deserialize SkPictures that contain slug data
    static void AddDeserialProcs(SkDeserialProcs* procs, const SkStrikeClient* client = nullptr);
 
    // Draw the Slug obeying the canvas's mapping and clipping.
    void draw(SkCanvas* canvas, const SkPaint& paint) const;
 
    virtual SkRect sourceBounds() const = 0;
    virtual SkRect sourceBoundsWithOrigin () const = 0;
 
    virtual void doFlatten(SkWriteBuffer&) const = 0;
 
    uint32_t uniqueID() const { return fUniqueID; }
 
private:
    static uint32_t NextUniqueID();
    const uint32_t  fUniqueID{NextUniqueID()};
};
 
 
}  // namespace sktext::gpu
 
#endif  // sktext_gpu_Slug_DEFINED