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 "include/core/SkCanvas.h"
9 #include "include/core/SkColorPriv.h"
10 #include "include/core/SkStream.h"
11 #include "include/core/SkString.h"
12 #include "include/core/SkTypes.h"
13 #include "samplecode/DecodeFile.h"
14 #include "samplecode/Sample.h"
15 #include "src/core/SkBlurMask.h"
16 #include "src/core/SkOSFile.h"
17 #include "src/utils/SkOSPath.h"
18 #include "src/utils/SkUTF.h"
19 #include "tools/Resources.h"
20 #include "tools/ToolUtils.h"
21
22 /**
23 * Interprets c as an unpremultiplied color, and returns the
24 * premultiplied equivalent.
25 */
premultiply_unpmcolor(SkPMColor c)26 static SkPMColor premultiply_unpmcolor(SkPMColor c) {
27 U8CPU a = SkGetPackedA32(c);
28 U8CPU r = SkGetPackedR32(c);
29 U8CPU g = SkGetPackedG32(c);
30 U8CPU b = SkGetPackedB32(c);
31 return SkPreMultiplyARGB(a, r, g, b);
32 }
33
34 class UnpremulView : public Sample {
35 public:
UnpremulView(SkString res)36 UnpremulView(SkString res)
37 : fResPath(res)
38 , fPremul(true)
39 , fDecodeSucceeded(false) {
40 this->nextImage();
41 }
42
43 protected:
name()44 SkString name() override { return SkString("unpremul"); }
45
onChar(SkUnichar uni)46 bool onChar(SkUnichar uni) override {
47 char utf8[SkUTF::kMaxBytesInUTF8Sequence];
48 size_t size = SkUTF::ToUTF8(uni, utf8);
49 // Only consider events for single char keys
50 if (1 == size) {
51 switch (utf8[0]) {
52 case fNextImageChar:
53 this->nextImage();
54 return true;
55 case fTogglePremulChar:
56 this->togglePremul();
57 return true;
58 default:
59 break;
60 }
61 }
62 return false;
63 }
64
onDrawBackground(SkCanvas * canvas)65 void onDrawBackground(SkCanvas* canvas) override {
66 ToolUtils::draw_checkerboard(canvas, 0xFFCCCCCC, 0xFFFFFFFF, 12);
67 }
68
onDrawContent(SkCanvas * canvas)69 void onDrawContent(SkCanvas* canvas) override {
70 SkPaint paint;
71 paint.setAntiAlias(true);
72
73 SkFont font;
74 font.setSize(24);
75 SkScalar height = font.getMetrics(nullptr);
76 if (!fDecodeSucceeded) {
77 SkString failure;
78 if (fResPath.size() == 0) {
79 failure.printf("resource path is required!");
80 } else {
81 failure.printf("Failed to decode %s", fCurrFile.c_str());
82 }
83 canvas->drawString(failure, 0, height, font, paint);
84 return;
85 }
86
87 // Name, size of the file, and whether or not it is premultiplied.
88 SkString header(SkOSPath::Basename(fCurrFile.c_str()));
89 header.appendf(" [%dx%d] %s", fBitmap.width(), fBitmap.height(),
90 (fPremul ? "premultiplied" : "unpremultiplied"));
91 canvas->drawString(header, 0, height, font, paint);
92 canvas->translate(0, height);
93
94 // Help messages
95 header.printf("Press '%c' to move to the next image.'", fNextImageChar);
96 canvas->drawString(header, 0, height, font, paint);
97 canvas->translate(0, height);
98
99 header.printf("Press '%c' to toggle premultiplied decode.", fTogglePremulChar);
100 canvas->drawString(header, 0, height, font, paint);
101
102 // Now draw the image itself.
103 canvas->translate(height * 2, height * 2);
104 if (!fPremul) {
105 // A premultiplied bitmap cannot currently be drawn.
106 // Copy it to a bitmap which can be drawn, converting
107 // to premultiplied:
108 SkBitmap bm;
109 bm.allocN32Pixels(fBitmap.width(), fBitmap.height());
110 for (int i = 0; i < fBitmap.width(); ++i) {
111 for (int j = 0; j < fBitmap.height(); ++j) {
112 *bm.getAddr32(i, j) = premultiply_unpmcolor(*fBitmap.getAddr32(i, j));
113 }
114 }
115 canvas->drawBitmap(bm, 0, 0);
116 } else {
117 canvas->drawBitmap(fBitmap, 0, 0);
118 }
119 }
120
121 private:
122 const SkString fResPath;
123 SkString fCurrFile;
124 bool fPremul;
125 bool fDecodeSucceeded;
126 SkBitmap fBitmap;
127 SkOSFile::Iter fFileIter;
128
129 static const char fNextImageChar = 'j';
130 static const char fTogglePremulChar = 'h';
131
nextImage()132 void nextImage() {
133 if (fResPath.size() == 0) {
134 return;
135 }
136 SkString basename;
137 if (!fFileIter.next(&basename)) {
138 fFileIter.reset(fResPath.c_str());
139 if (!fFileIter.next(&basename)) {
140 // Perhaps this should draw some error message?
141 return;
142 }
143 }
144 fCurrFile = SkOSPath::Join(fResPath.c_str(), basename.c_str());
145 this->decodeCurrFile();
146 }
147
decodeCurrFile()148 void decodeCurrFile() {
149 if (fCurrFile.size() == 0) {
150 fDecodeSucceeded = false;
151 return;
152 }
153 fDecodeSucceeded = decode_file(fCurrFile.c_str(), &fBitmap, kN32_SkColorType, !fPremul);
154 }
155
togglePremul()156 void togglePremul() {
157 fPremul = !fPremul;
158 this->decodeCurrFile();
159 }
160
161 typedef Sample INHERITED;
162 };
163
164 //////////////////////////////////////////////////////////////////////////////
165
166 DEF_SAMPLE( return new UnpremulView(GetResourcePath("images")); )
167