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 "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/SkImageFilter.h"
13 #include "include/core/SkMatrix.h"
14 #include "include/core/SkPaint.h"
15 #include "include/core/SkRect.h"
16 #include "include/core/SkRefCnt.h"
17 #include "include/core/SkSamplingOptions.h"
18 #include "include/core/SkScalar.h"
19 #include "include/core/SkSize.h"
20 #include "include/core/SkString.h"
21 #include "include/effects/SkImageFilters.h"
22 #include "tools/ToolUtils.h"
23
24 #include <utility>
25
make_bm(SkBitmap * bm)26 static void make_bm(SkBitmap* bm) {
27 bm->allocN32Pixels(100, 100);
28 bm->eraseColor(SK_ColorBLUE);
29
30 SkCanvas canvas(*bm);
31 SkPaint paint;
32 paint.setAntiAlias(true);
33 paint.setColor(SK_ColorRED);
34 canvas.drawCircle(50, 50, 50, paint);
35 }
36
draw_1_bitmap(SkCanvas * canvas,const SkBitmap & bm,bool doClip,int dx,int dy,sk_sp<SkImageFilter> filter)37 static void draw_1_bitmap(SkCanvas* canvas, const SkBitmap& bm, bool doClip,
38 int dx, int dy, sk_sp<SkImageFilter> filter) {
39 SkAutoCanvasRestore acr(canvas, true);
40 SkPaint paint;
41
42 SkRect clipR = SkRect::MakeXYWH(SkIntToScalar(dx),
43 SkIntToScalar(dy),
44 SkIntToScalar(bm.width()),
45 SkIntToScalar(bm.height()));
46
47 paint.setImageFilter(std::move(filter));
48 clipR.inset(5, 5);
49
50 canvas->translate(SkIntToScalar(bm.width() + 20), 0);
51
52 if (doClip) {
53 canvas->save();
54 canvas->clipRect(clipR);
55 }
56 canvas->drawImage(bm.asImage(), SkIntToScalar(dx), SkIntToScalar(dy),
57 SkSamplingOptions(), &paint);
58 if (doClip) {
59 canvas->restore();
60 }
61 }
62
63 /**
64 * Compare output of drawSprite and drawBitmap (esp. clipping and imagefilters)
65 */
66 class SpriteBitmapGM : public skiagm::GM {
67 public:
SpriteBitmapGM()68 SpriteBitmapGM() {}
69
70 protected:
getName() const71 SkString getName() const override { return SkString("spritebitmap"); }
72
getISize()73 SkISize getISize() override { return SkISize::Make(640, 480); }
74
onDraw(SkCanvas * canvas)75 void onDraw(SkCanvas* canvas) override {
76 SkBitmap bm;
77 make_bm(&bm);
78
79 int dx = 10;
80 int dy = 10;
81
82 SkScalar sigma = 8;
83 sk_sp<SkImageFilter> filter(SkImageFilters::Blur(sigma, sigma, nullptr));
84
85 draw_1_bitmap(canvas, bm, false, dx, dy, nullptr);
86 dy += bm.height() + 20;
87 draw_1_bitmap(canvas, bm, false, dx, dy, filter);
88 dy += bm.height() + 20;
89 draw_1_bitmap(canvas, bm, true, dx, dy, nullptr);
90 dy += bm.height() + 20;
91 draw_1_bitmap(canvas, bm, true, dx, dy, filter);
92 }
93
94 private:
95 using INHERITED = GM;
96 };
97 DEF_GM( return new SpriteBitmapGM; )
98
99 // b/41322892 : The CPU backend tries to detect when an image draw is landing perfectly on pixel
100 // centers, so it can use a faster sprite-blitting path. That code just assumes that ANY translation
101 // can be pixel-snapped. Image-shaders used to behave like this, but were fixed long-ago.
102 // The correct result here is for ALL rectangles to be averaged to grey, rather than a pixel-snapped
103 // black and white checkerboard.
104 //
105 // This GM now tests that linear filtering is preserved for subpixel translation, across several
106 // different possible methods of drawing.
107 DEF_SIMPLE_GM_BG(drawimagerect_filter, canvas, 180, 60, SK_ColorWHITE) {
108 auto image = ToolUtils::create_checkerboard_image(50, 50, SK_ColorWHITE, SK_ColorBLACK, 1);
109 SkSamplingOptions sampling{SkFilterMode::kLinear};
110
111 canvas->translate(5, 5);
112 canvas->drawImage(image, 0.5f, 0.5f, sampling);
113
114 canvas->translate(60, 0);
115 canvas->drawImageRect(image, {0.5f, 0.5f, 50.5f, 50.5f}, sampling);
116
117 auto shader = image->makeShader(sampling);
118 canvas->translate(60, 0);
119 SkPaint paint;
120 SkMatrix offset = SkMatrix::Translate(0.5f, 0.5f);
121 paint.setShader(image->makeShader(sampling, &offset));
122 canvas->drawRect({0.0f, 0.0f, 50.0f, 50.0f}, paint);
123 }
124