1 /*
2 * Copyright 2014 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
10 #include "Resources.h"
11 #include "SampleCode.h"
12 #include "SkBlurMaskFilter.h"
13 #include "SkCanvas.h"
14 #include "SkColorPriv.h"
15 #include "SkImageDecoder.h"
16 #include "SkRandom.h"
17 #include "SkStream.h"
18
19 // Intended to exercise pixel snapping observed with scaled images (and
20 // with non-scaled images, but for a different reason): Bug 1145
21
22 class SubpixelTranslateView : public SampleView {
23 public:
SubpixelTranslateView(const char imageFilename[],float horizontalVelocity,float verticalVelocity)24 SubpixelTranslateView(const char imageFilename[],
25 float horizontalVelocity,
26 float verticalVelocity)
27 : fHorizontalVelocity(horizontalVelocity),
28 fVerticalVelocity(verticalVelocity) {
29 SkString resourcePath = GetResourcePath(imageFilename);
30 SkImageDecoder* codec = nullptr;
31 SkFILEStream stream(resourcePath.c_str());
32 if (stream.isValid()) {
33 codec = SkImageDecoder::Factory(&stream);
34 }
35 if (codec) {
36 stream.rewind();
37 codec->decode(&stream, &fBM, kN32_SkColorType, SkImageDecoder::kDecodePixels_Mode);
38 delete codec;
39 } else {
40 fBM.allocN32Pixels(1, 1);
41 *(fBM.getAddr32(0,0)) = 0xFF0000FF; // red == bad
42 }
43 fCurPos = SkPoint::Make(0,0);
44 fSize = 200;
45 }
46
47 protected:
48 SkBitmap fBM;
49 SkScalar fSize;
50 float fHorizontalVelocity, fVerticalVelocity;
51
52 SkPoint fCurPos;
53
54 // overrides from SkEventSink
onQuery(SkEvent * evt)55 bool onQuery(SkEvent* evt) override {
56 if (SampleCode::TitleQ(*evt)) {
57 SampleCode::TitleR(evt, "SubpixelTranslate");
58 return true;
59 }
60 return this->INHERITED::onQuery(evt);
61 }
62
onDrawContent(SkCanvas * canvas)63 void onDrawContent(SkCanvas* canvas) override {
64
65 static const SkFilterQuality gQualitys[] = {
66 kNone_SkFilterQuality,
67 kLow_SkFilterQuality,
68 kMedium_SkFilterQuality,
69 kHigh_SkFilterQuality
70 };
71
72 SkPaint paint;
73 paint.setTextSize(48);
74 paint.setSubpixelText(true);
75
76 paint.setAntiAlias(true);
77 for (size_t i = 0; i < SK_ARRAY_COUNT(gQualitys); ++i) {
78 paint.setFilterQuality(gQualitys[i]);
79 SkRect r = SkRect::MakeXYWH( fCurPos.fX + i * (fSize + 10), fCurPos.fY, fSize, fSize );
80 canvas->drawBitmapRect( fBM, r, &paint );
81 }
82
83 canvas->drawText( "AA Scaled", strlen("AA Scaled"), fCurPos.fX + SK_ARRAY_COUNT(gQualitys) * (fSize + 10), fCurPos.fY + fSize/2, paint );
84
85 paint.setAntiAlias(false);
86 for (size_t i = 0; i < SK_ARRAY_COUNT(gQualitys); ++i) {
87 paint.setFilterQuality(gQualitys[i]);
88 SkRect r = SkRect::MakeXYWH( fCurPos.fX + i * (fSize + 10), fCurPos.fY + fSize + 10, fSize, fSize );
89 canvas->drawBitmapRect( fBM, r, &paint );
90 }
91 canvas->drawText( "Scaled", strlen("Scaled"), fCurPos.fX + SK_ARRAY_COUNT(gQualitys) * (fSize + 10), fCurPos.fY + fSize + 10 + fSize/2, paint );
92
93 paint.setAntiAlias(true);
94 for (size_t i = 0; i < SK_ARRAY_COUNT(gQualitys); ++i) {
95 paint.setFilterQuality(gQualitys[i]);
96 canvas->drawBitmap( fBM, fCurPos.fX + i * (fBM.width() + 10), fCurPos.fY + 2*(fSize + 10), &paint );
97 }
98
99 canvas->drawText( "AA No Scale", strlen("AA No Scale"), fCurPos.fX + SK_ARRAY_COUNT(gQualitys) * (fBM.width() + 10), fCurPos.fY + 2*(fSize + 10) + fSize/2, paint );
100
101 paint.setAntiAlias(false);
102 for (size_t i = 0; i < SK_ARRAY_COUNT(gQualitys); ++i) {
103 paint.setFilterQuality(gQualitys[i]);
104 canvas->drawBitmap( fBM, fCurPos.fX + i * (fBM.width() + 10), fCurPos.fY + 2*(fSize + 10) + fBM.height() + 10, &paint );
105 }
106
107 canvas->drawText( "No Scale", strlen("No Scale"), fCurPos.fX + SK_ARRAY_COUNT(gQualitys) * (fBM.width() + 10), fCurPos.fY + 2*(fSize + 10) + fBM.height() + 10 + fSize/2, paint );
108
109
110 fCurPos.fX += fHorizontalVelocity;
111 fCurPos.fY += fVerticalVelocity;
112 this->inval(nullptr);
113 }
114
115 private:
116 typedef SampleView INHERITED;
117 };
118
119 //////////////////////////////////////////////////////////////////////////////
120
MyFactory()121 static SkView* MyFactory() { return new SubpixelTranslateView("mandrill_256.png", .05f, .05f); }
122 static SkViewRegister reg(MyFactory);
123