1 /*
2  * Copyright 2017 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 "gm.h"
9 #include "SkBlurImageFilter.h"
10 
11 // For all sigma, the black box should be centered in the red outline. For small sigma,
12 // the rectangle is not blurred, but still must be centered properly.
13 
14 DEF_SIMPLE_GM(check_small_sigma_offset, canvas, 200, 1200) {
15 
16     for (auto sigma : {0.0, 0.1, 0.2, 0.3, 0.4, 0.6, 0.8, 1.0, 1.2}) {
17         // border calculation from SkBlurImageFilter
18         int border = SkScalarCeilToInt(sigma * 3);
19 
20         SkRect r = SkRect::MakeXYWH(50, 50, 100, 50);
21         SkRect b = r.makeOutset(border + 1, border + 1);
22         b.inset(0.5f, 0.5f);
23         SkPaint p;
24         p.setColor(SK_ColorRED);
25         p.setStyle(SkPaint::Style::kStroke_Style);
26 
27         canvas->drawRect(b, p);
28 
29         p.reset();
30         p.setColor(SK_ColorBLACK);
31         p.setImageFilter(SkBlurImageFilter::Make(sigma, sigma, nullptr));
32         canvas->drawRect(r, p);
33 
34         canvas->translate(0, 100);
35     }
36 }
37