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/gm.h"
9 #include "include/core/SkBitmap.h"
10 #include "include/core/SkCanvas.h"
11 #include "include/core/SkColor.h"
12 #include "include/core/SkImage.h"
13 #include "include/core/SkImageFilter.h"
14 #include "include/core/SkImageInfo.h"
15 #include "include/core/SkPaint.h"
16 #include "include/core/SkRect.h"
17 #include "include/core/SkRefCnt.h"
18 #include "include/core/SkScalar.h"
19 #include "include/core/SkSize.h"
20 #include "include/core/SkString.h"
21 #include "include/core/SkSurface.h"
22 #include "include/effects/SkImageFilters.h"
23 #include "tools/ToolUtils.h"
24
25 #include <initializer_list>
26 #include <utility>
27
make_image(SkCanvas * canvas,int direction)28 static sk_sp<SkImage> make_image(SkCanvas* canvas, int direction) {
29 SkImageInfo info = SkImageInfo::MakeN32Premul(250, 200);
30 auto surface = ToolUtils::makeSurface(canvas, info);
31 SkCanvas* c = surface->getCanvas();
32 SkPaint paint;
33 paint.setAntiAlias(true);
34
35 const SkColor colors[] = {
36 SK_ColorRED, SK_ColorBLUE, SK_ColorGREEN, SK_ColorYELLOW, SK_ColorBLACK
37 };
38
39 int width = 25;
40 bool xDirection = (direction & 0x1) == 1;
41 bool yDirection = (direction & 0x2) == 2;
42 if (xDirection) {
43 for (int x = 0; x < info.width(); x += width) {
44 paint.setColor(colors[x/width % 5]);
45 if (yDirection) {
46 paint.setAlphaf(0.5f);
47 }
48 c->drawRect(SkRect::MakeXYWH(x, 0, width, info.height()), paint);
49 }
50 }
51
52 if (yDirection) {
53 for (int y = 0; y < info.height(); y += width) {
54 paint.setColor(colors[y/width % 5]);
55 if (xDirection) {
56 paint.setAlphaf(0.5f);
57 }
58 c->drawRect(SkRect::MakeXYWH(0, y, info.width(), width), paint);
59 }
60 }
61 return surface->makeImageSnapshot();
62 }
63
draw_image(SkCanvas * canvas,const sk_sp<SkImage> image,sk_sp<SkImageFilter> filter)64 static void draw_image(SkCanvas* canvas, const sk_sp<SkImage> image, sk_sp<SkImageFilter> filter) {
65 SkAutoCanvasRestore acr(canvas, true);
66 SkPaint paint;
67 paint.setImageFilter(std::move(filter));
68
69 canvas->translate(SkIntToScalar(30), 0);
70 canvas->clipIRect(image->bounds());
71 canvas->drawImage(image, 0, 0, SkSamplingOptions(), &paint);
72 }
73
74 namespace skiagm {
75
76 // This GM draws a colorful grids with different blur settings.
77 class ImageBlurRepeatModeGM : public GM {
78 public:
ImageBlurRepeatModeGM()79 ImageBlurRepeatModeGM() {
80 this->setBGColor(0xFFCCCCCC);
81 }
82
83 protected:
getName() const84 SkString getName() const override { return SkString("imageblurrepeatmode"); }
85
getISize()86 SkISize getISize() override { return SkISize::Make(850, 920); }
87
runAsBench() const88 bool runAsBench() const override { return true; }
89
onDraw(SkCanvas * canvas)90 void onDraw(SkCanvas* canvas) override {
91 sk_sp<SkImage> image[] =
92 { make_image(canvas, 1), make_image(canvas, 2), make_image(canvas, 3) };
93 sk_sp<SkImageFilter> filter;
94
95 canvas->translate(0, 30);
96 // Test different kernel size, including the one to launch 2d Gaussian
97 // blur.
98 for (auto sigma: { 0.6f, 3.0f, 8.0f, 20.0f }) {
99 // FIXME crops
100 canvas->save();
101 filter = SkImageFilters::Blur(
102 sigma, 0.0f, SkTileMode::kRepeat, nullptr, image[0]->bounds());
103 draw_image(canvas, image[0], std::move(filter));
104 canvas->translate(image[0]->width() + 20, 0);
105
106 filter = SkImageFilters::Blur(
107 0.0f, sigma, SkTileMode::kRepeat, nullptr, image[1]->bounds());
108 draw_image(canvas, image[1], std::move(filter));
109 canvas->translate(image[1]->width() + 20, 0);
110
111 filter = SkImageFilters::Blur(
112 sigma, sigma, SkTileMode::kRepeat, nullptr, image[2]->bounds());
113 draw_image(canvas, image[2], std::move(filter));
114 canvas->translate(image[2]->width() + 20, 0);
115
116 canvas->restore();
117 canvas->translate(0, image[0]->height() + 20);
118 }
119 }
120
121 private:
122 using INHERITED = GM;
123 };
124
125 //////////////////////////////////////////////////////////////////////////////
126
127 DEF_GM(return new ImageBlurRepeatModeGM;)
128 } // namespace skiagm
129
130 // See skbug.com/10145 for more context, but if the blur doesn't have its own crop rect and
131 // the canvas is not clipped, repeat can behave strangely (before fixes, this meant:
132 // 1. The filtered results became semi-transparent when they should have remained opaque.
133 // 2. The filtered results clip to 3xSigma, which makes sense for the decal tile mode, but not
134 // the others.
135 // 3. The repeat filter interacts non-intuitively when an expanded clip rect intersects the draw
136 // geometry (it repeats across the edges of the intersection instead of repeating across the
137 // draw and then clipping)).
138 DEF_SIMPLE_GM(imageblurrepeatunclipped, canvas, 256, 128) {
139 // To show translucency
140 auto checkerboard = ToolUtils::create_checkerboard_image(256, 128, SK_ColorLTGRAY,
141 SK_ColorGRAY, 8);
142 canvas->drawImage(checkerboard, 0, 0);
143
144 // Make an image with one red and one blue band
145 SkBitmap bmp;
146 bmp.allocN32Pixels(100, 20);
147 bmp.eraseArea(SkIRect::MakeWH(100, 10), SK_ColorRED);
148 bmp.eraseArea(SkIRect::MakeXYWH(0, 10, 100, 10), SK_ColorBLUE);
149
150 auto img = bmp.asImage();
151 // The blur filter uses a repeat crop applied to the image bounds to define the tiling geometry,
152 // but the crop IF is created directly since the tilemode factory for ::Blur also adds a kDecal
153 // post-crop that is undesired for this GM.
154 auto filter = SkImageFilters::Blur(0, 10,
155 SkImageFilters::Crop(SkRect::Make(img->bounds()), SkTileMode::kRepeat, nullptr));
156 SkPaint paint;
157 paint.setImageFilter(std::move(filter));
158
159 // Draw the blurred image once with a clip that shows the repeat is tiled several times.
160 // 3xsigma is used to match the historic, but underspecified behavior for when kRepeat was used
161 // with no crop rect (which must now be provided or kRepeat is ignored).
162 canvas->translate(0, 50);
163 canvas->save();
164 canvas->clipIRect(img->bounds().makeOutset(0, 30));
165 canvas->drawImage(img, 0, 0, SkSamplingOptions(), &paint);
166 canvas->restore();
167
168 // Draw the blurred image with a clip positioned such that the draw would be excluded except
169 // that the image filter causes it to intersect with the clip. It should look like the
170 // left image, but clipped to the debug-black rectangle.
171 canvas->translate(110, 0);
172 canvas->save();
173 canvas->clipIRect(SkIRect::MakeXYWH(0, -30, 100, 10));
174 canvas->drawImage(img, 0, 0, SkSamplingOptions(), &paint);
175 canvas->restore();
176
177 // Visualize the clip
178 SkPaint line;
179 line.setStyle(SkPaint::kStroke_Style);
180 canvas->drawRect(SkRect::MakeXYWH(0, -30, 99, 9), line);
181 }
182