1 /*
2  * Copyright 2015 Google Inc.
3  *
4  * Use of this source code is governed by a BSD-style license that can be
5  * found in the LICENSE file.
6  */
7 
8 #ifndef SkMiniRecorder_DEFINED
9 #define SkMiniRecorder_DEFINED
10 
11 #include "SkRecords.h"
12 #include "SkScalar.h"
13 #include "SkTypes.h"
14 class SkCanvas;
15 
16 // Records small pictures, but only a limited subset of the canvas API, and may fail.
17 class SkMiniRecorder : SkNoncopyable {
18 public:
19     SkMiniRecorder();
20     ~SkMiniRecorder();
21 
22     // Try to record an op.  Returns false on failure.
23     bool drawPath(const SkPath&, const SkPaint&);
24     bool drawRect(const SkRect&, const SkPaint&);
25     bool drawTextBlob(const SkTextBlob*, SkScalar x, SkScalar y, const SkPaint&);
26 
27     // Detach anything we've recorded as a picture, resetting this SkMiniRecorder.
28     sk_sp<SkPicture> detachAsPicture(const SkRect& cull);
29 
30     // Flush anything we've recorded to the canvas, resetting this SkMiniRecorder.
31     // This is logically the same as but rather more efficient than:
32     //    sk_sp<SkPicture> pic(this->detachAsPicture(SkRect::MakeEmpty()));
33     //    pic->playback(canvas);
34     void flushAndReset(SkCanvas*);
35 
36 private:
37     enum class State {
38         kEmpty,
39         kDrawPath,
40         kDrawRect,
41         kDrawTextBlob,
42     };
43 
44     State fState;
45 
46     template <size_t A, size_t B>
47     struct Max { static const size_t val = A > B ? A : B; };
48 
49     static const size_t kInlineStorage =
50         Max<sizeof(SkRecords::DrawPath),
51         Max<sizeof(SkRecords::DrawRect),
52             sizeof(SkRecords::DrawTextBlob)>::val>::val;
53     SkAlignedSStorage<kInlineStorage> fBuffer;
54 };
55 
56 #endif//SkMiniRecorder_DEFINED
57