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/SkBlendMode.h"
11 #include "include/core/SkCanvas.h"
12 #include "include/core/SkColor.h"
13 #include "include/core/SkColorPriv.h"
14 #include "include/core/SkImageInfo.h"
15 #include "include/core/SkPaint.h"
16 #include "include/core/SkScalar.h"
17 #include "include/core/SkSize.h"
18 #include "include/core/SkString.h"
19 #include "include/core/SkTypes.h"
20
21 /**
22 * This GM checks that bitmap pixels are unpremultiplied before being exported
23 * to other formats. If unpremultiplication is implemented properly, this
24 * GM should come out completely white. If not, this GM looks like a row of two
25 * greyscale gradients above a row of grey lines.
26 * This tests both the ARGB4444 and ARGB8888 bitmap configurations.
27 */
28
29 constexpr int SLIDE_SIZE = 256;
30
init_bitmap(SkColorType ct,SkBitmap * bitmap)31 static void init_bitmap(SkColorType ct, SkBitmap* bitmap) {
32 bitmap->allocPixels(SkImageInfo::Make(SLIDE_SIZE, SLIDE_SIZE, ct,
33 kPremul_SkAlphaType));
34 bitmap->eraseColor(SK_ColorWHITE);
35 }
36
make_argb8888_gradient()37 static SkBitmap make_argb8888_gradient() {
38 SkBitmap bitmap;
39 init_bitmap(kN32_SkColorType, &bitmap);
40 for (int y = 0; y < SLIDE_SIZE; y++) {
41 uint32_t* dst = bitmap.getAddr32(0, y);
42 for (int x = 0; x < SLIDE_SIZE; x++) {
43 dst[x] = SkPackARGB32(y, y, y, y);
44 }
45 }
46 return bitmap;
47 }
48
make_argb4444_gradient()49 static SkBitmap make_argb4444_gradient() {
50 SkBitmap bitmap;
51 init_bitmap(kARGB_4444_SkColorType, &bitmap);
52 // Using draw rather than readPixels to suppress dither
53 SkPaint paint;
54 paint.setBlendMode(SkBlendMode::kSrc);
55 SkCanvas{ bitmap }.drawBitmap(make_argb8888_gradient(), 0, 0, &paint);
56 return bitmap;
57 }
58
make_argb8888_stripes()59 static SkBitmap make_argb8888_stripes() {
60 SkBitmap bitmap;
61 init_bitmap(kN32_SkColorType, &bitmap);
62 uint8_t rowColor = 0;
63 for (int y = 0; y < SLIDE_SIZE; y++) {
64 uint32_t* dst = bitmap.getAddr32(0, y);
65 for (int x = 0; x < SLIDE_SIZE; x++) {
66 dst[x] = SkPackARGB32(rowColor, rowColor,
67 rowColor, rowColor);
68 }
69 if (rowColor == 0) {
70 rowColor = 255;
71 } else {
72 rowColor = 0;
73 }
74 }
75 return bitmap;
76 }
77
make_argb4444_stripes()78 static SkBitmap make_argb4444_stripes() {
79 SkBitmap bitmap;
80 init_bitmap(kARGB_4444_SkColorType, &bitmap);
81 // Using draw rather than readPixels to suppress dither
82 SkPaint paint;
83 paint.setBlendMode(SkBlendMode::kSrc);
84 SkCanvas{ bitmap }.drawBitmap(make_argb8888_stripes(), 0, 0, &paint);
85 return bitmap;
86 }
87
88 namespace skiagm {
89
90 class BitmapPremulGM : public GM {
91 public:
BitmapPremulGM()92 BitmapPremulGM() {
93 this->setBGColor(SK_ColorWHITE);
94 }
95
96 protected:
onShortName()97 SkString onShortName() override {
98 return SkString("bitmap_premul");
99 }
100
onISize()101 SkISize onISize() override {
102 return SkISize::Make(SLIDE_SIZE * 2, SLIDE_SIZE * 2);
103 }
104
onDraw(SkCanvas * canvas)105 void onDraw(SkCanvas* canvas) override {
106 SkScalar slideSize = SkIntToScalar(SLIDE_SIZE);
107 canvas->drawBitmap(make_argb8888_gradient(), 0, 0);
108 canvas->drawBitmap(make_argb4444_gradient(), slideSize, 0);
109 canvas->drawBitmap(make_argb8888_stripes(), 0, slideSize);
110 canvas->drawBitmap(make_argb4444_stripes(), slideSize, slideSize);
111 }
112
113 private:
114 typedef GM INHERITED;
115 };
116
117 DEF_GM( return new BitmapPremulGM; )
118 }
119