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.h"
9
10 #include "sk_tool_utils.h"
11 #include "Resources.h"
12 #include "SampleCode.h"
13 #include "SkBlurMask.h"
14 #include "SkBlurDrawLooper.h"
15 #include "SkCanvas.h"
16 #include "SkColorPriv.h"
17 #include "SkForceLinking.h"
18 #include "SkImageDecoder.h"
19 #include "SkOSFile.h"
20 #include "SkStream.h"
21 #include "SkString.h"
22 #include "SkSystemEventTypes.h"
23 #include "SkTypes.h"
24 #include "SkUtils.h"
25 #include "SkView.h"
26
27 __SK_FORCE_IMAGE_DECODER_LINKING;
28
29 /**
30 * Interprets c as an unpremultiplied color, and returns the
31 * premultiplied equivalent.
32 */
premultiply_unpmcolor(SkPMColor c)33 static SkPMColor premultiply_unpmcolor(SkPMColor c) {
34 U8CPU a = SkGetPackedA32(c);
35 U8CPU r = SkGetPackedR32(c);
36 U8CPU g = SkGetPackedG32(c);
37 U8CPU b = SkGetPackedB32(c);
38 return SkPreMultiplyARGB(a, r, g, b);
39 }
40
41 class UnpremulView : public SampleView {
42 public:
UnpremulView(SkString res)43 UnpremulView(SkString res)
44 : fResPath(res)
45 , fPremul(true)
46 , fDecodeSucceeded(false) {
47 this->nextImage();
48 }
49
50 protected:
51 // overrides from SkEventSink
onQuery(SkEvent * evt)52 bool onQuery(SkEvent* evt) override {
53 if (SampleCode::TitleQ(*evt)) {
54 SampleCode::TitleR(evt, "unpremul");
55 return true;
56 }
57 SkUnichar uni;
58 if (SampleCode::CharQ(*evt, &uni)) {
59 char utf8[kMaxBytesInUTF8Sequence];
60 size_t size = SkUTF8_FromUnichar(uni, utf8);
61 // Only consider events for single char keys
62 if (1 == size) {
63 switch (utf8[0]) {
64 case fNextImageChar:
65 this->nextImage();
66 return true;
67 case fTogglePremulChar:
68 this->togglePremul();
69 return true;
70 default:
71 break;
72 }
73 }
74 }
75 return this->INHERITED::onQuery(evt);
76 }
77
onDrawBackground(SkCanvas * canvas)78 void onDrawBackground(SkCanvas* canvas) override {
79 sk_tool_utils::draw_checkerboard(canvas, 0xFFCCCCCC, 0xFFFFFFFF, 12);
80 }
81
onDrawContent(SkCanvas * canvas)82 void onDrawContent(SkCanvas* canvas) override {
83 SkPaint paint;
84 paint.setAntiAlias(true);
85 paint.setTextSize(SkIntToScalar(24));
86 SkAutoTUnref<SkDrawLooper> looper(
87 SkBlurDrawLooper::Create(SK_ColorBLUE,
88 SkBlurMask::ConvertRadiusToSigma(SkIntToScalar(2)),
89 0, 0));
90 paint.setLooper(looper);
91 SkScalar height = paint.getFontMetrics(nullptr);
92 if (!fDecodeSucceeded) {
93 SkString failure;
94 if (fResPath.size() == 0) {
95 failure.printf("resource path is required!");
96 } else {
97 failure.printf("Failed to decode %s", fCurrFile.c_str());
98 }
99 canvas->drawText(failure.c_str(), failure.size(), 0, height, paint);
100 return;
101 }
102
103 // Name, size of the file, and whether or not it is premultiplied.
104 SkString header(SkOSPath::Basename(fCurrFile.c_str()));
105 header.appendf(" [%dx%d] %s", fBitmap.width(), fBitmap.height(),
106 (fPremul ? "premultiplied" : "unpremultiplied"));
107 canvas->drawText(header.c_str(), header.size(), 0, height, paint);
108 canvas->translate(0, height);
109
110 // Help messages
111 header.printf("Press '%c' to move to the next image.'", fNextImageChar);
112 canvas->drawText(header.c_str(), header.size(), 0, height, paint);
113 canvas->translate(0, height);
114
115 header.printf("Press '%c' to toggle premultiplied decode.", fTogglePremulChar);
116 canvas->drawText(header.c_str(), header.size(), 0, height, paint);
117
118 // Now draw the image itself.
119 canvas->translate(height * 2, height * 2);
120 if (!fPremul) {
121 // A premultiplied bitmap cannot currently be drawn.
122 SkAutoLockPixels alp(fBitmap);
123 // Copy it to a bitmap which can be drawn, converting
124 // to premultiplied:
125 SkBitmap bm;
126 bm.allocN32Pixels(fBitmap.width(), fBitmap.height());
127 for (int i = 0; i < fBitmap.width(); ++i) {
128 for (int j = 0; j < fBitmap.height(); ++j) {
129 *bm.getAddr32(i, j) = premultiply_unpmcolor(*fBitmap.getAddr32(i, j));
130 }
131 }
132 canvas->drawBitmap(bm, 0, 0);
133 } else {
134 canvas->drawBitmap(fBitmap, 0, 0);
135 }
136 }
137
138 private:
139 const SkString fResPath;
140 SkString fCurrFile;
141 bool fPremul;
142 bool fDecodeSucceeded;
143 SkBitmap fBitmap;
144 SkOSFile::Iter fFileIter;
145
146 static const char fNextImageChar = 'j';
147 static const char fTogglePremulChar = 'h';
148
nextImage()149 void nextImage() {
150 if (fResPath.size() == 0) {
151 return;
152 }
153 SkString basename;
154 if (!fFileIter.next(&basename)) {
155 fFileIter.reset(fResPath.c_str());
156 if (!fFileIter.next(&basename)) {
157 // Perhaps this should draw some error message?
158 return;
159 }
160 }
161 fCurrFile = SkOSPath::Join(fResPath.c_str(), basename.c_str());
162 this->decodeCurrFile();
163 }
164
decodeCurrFile()165 void decodeCurrFile() {
166 if (fCurrFile.size() == 0) {
167 fDecodeSucceeded = false;
168 return;
169 }
170 SkFILEStream stream(fCurrFile.c_str());
171 SkAutoTDelete<SkImageDecoder> decoder(SkImageDecoder::Factory(&stream));
172 if (nullptr == decoder.get()) {
173 fDecodeSucceeded = false;
174 return;
175 }
176 if (!fPremul) {
177 decoder->setRequireUnpremultipliedColors(true);
178 }
179 fDecodeSucceeded = decoder->decode(&stream, &fBitmap, kN32_SkColorType,
180 SkImageDecoder::kDecodePixels_Mode) != SkImageDecoder::kFailure;
181 this->inval(nullptr);
182 }
183
togglePremul()184 void togglePremul() {
185 fPremul = !fPremul;
186 this->decodeCurrFile();
187 }
188
189 typedef SampleView INHERITED;
190 };
191
192 //////////////////////////////////////////////////////////////////////////////
193
MyFactory()194 static SkView* MyFactory() {
195 return new UnpremulView(GetResourcePath());
196 }
197 static SkViewRegister reg(MyFactory);
198