1 /*
2  * Copyright 2013 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 #include "SkDrawLooper.h"
9 #include "SkCanvas.h"
10 #include "SkMatrix.h"
11 #include "SkPaint.h"
12 #include "SkRect.h"
13 #include "SkSmallAllocator.h"
14 
canComputeFastBounds(const SkPaint & paint) const15 bool SkDrawLooper::canComputeFastBounds(const SkPaint& paint) const {
16     SkCanvas canvas;
17     SkSmallAllocator<1, 32> allocator;
18     void* buffer = allocator.reserveT<SkDrawLooper::Context>(this->contextSize());
19 
20     SkDrawLooper::Context* context = this->createContext(&canvas, buffer);
21     for (;;) {
22         SkPaint p(paint);
23         if (context->next(&canvas, &p)) {
24             p.setLooper(NULL);
25             if (!p.canComputeFastBounds()) {
26                 return false;
27             }
28         } else {
29             break;
30         }
31     }
32     return true;
33 }
34 
computeFastBounds(const SkPaint & paint,const SkRect & s,SkRect * dst) const35 void SkDrawLooper::computeFastBounds(const SkPaint& paint, const SkRect& s,
36                                      SkRect* dst) const {
37     // src and dst rects may alias and we need to keep the original src, so copy it.
38     const SkRect src = s;
39 
40     SkCanvas canvas;
41     SkSmallAllocator<1, 32> allocator;
42     void* buffer = allocator.reserveT<SkDrawLooper::Context>(this->contextSize());
43 
44     *dst = src;   // catch case where there are no loops
45     SkDrawLooper::Context* context = this->createContext(&canvas, buffer);
46     for (bool firstTime = true;; firstTime = false) {
47         SkPaint p(paint);
48         if (context->next(&canvas, &p)) {
49             SkRect r(src);
50 
51             p.setLooper(NULL);
52             p.computeFastBounds(r, &r);
53             canvas.getTotalMatrix().mapRect(&r);
54 
55             if (firstTime) {
56                 *dst = r;
57             } else {
58                 dst->join(r);
59             }
60         } else {
61             break;
62         }
63     }
64 }
65 
asABlurShadow(BlurShadowRec *) const66 bool SkDrawLooper::asABlurShadow(BlurShadowRec*) const {
67     return false;
68 }
69