1 /*
2  * Copyright 2015 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 #include "sk_tool_utils.h"
10 #include "SkCanvas.h"
11 #include "SkImage.h"
12 #include "SkRandom.h"
13 #include "SkSurface.h"
14 
15 static sk_sp<SkImage> make_image() {
16     const SkImageInfo info = SkImageInfo::MakeN32Premul(319, 52);
17     auto surface(SkSurface::MakeRaster(info));
18     SkCanvas* canvas = surface->getCanvas();
19     canvas->drawColor(sk_tool_utils::color_to_565(0xFFF8F8F8));
20 
21     SkPaint paint;
22     paint.setAntiAlias(true);
23 
24     paint.setStyle(SkPaint::kStroke_Style);
25     for (int i = 0; i < 20; ++i) {
26         canvas->drawCircle(-4, 25, 20, paint);
27         canvas->translate(25, 0);
28     }
29     return surface->makeImageSnapshot();
30 }
31 
32 DEF_SIMPLE_GM(mipmap, canvas, 400, 200) {
33     sk_sp<SkImage> img(make_image());//SkImage::NewFromEncoded(data));
34 
35     SkPaint paint;
36     const SkRect dst = SkRect::MakeWH(177, 15);
37 
38     paint.setTextSize(30);
39     SkString str;
40     str.printf("scale %g %g", dst.width() / img->width(), dst.height() / img->height());
41 //    canvas->drawString(str, 300, 100, paint);
42 
43     canvas->translate(20, 20);
44     for (int i = 0; i < 4; ++i) {
45         paint.setFilterQuality(SkFilterQuality(i));
46         canvas->drawImageRect(img.get(), dst, &paint);
47         canvas->translate(0, 20);
48     }
49     canvas->drawImage(img.get(), 20, 20, nullptr);
50 }
51 
52 ///////////////////////////////////////////////////////////////////////////////////////////////////
53 
54 // create a circle image computed raw, so we can wrap it as a linear or srgb image
55 static sk_sp<SkImage> make(sk_sp<SkColorSpace> cs) {
56     const int N = 100;
57     SkImageInfo info = SkImageInfo::Make(N, N, kN32_SkColorType, kPremul_SkAlphaType, cs);
58     SkBitmap bm;
59     bm.allocPixels(info);
60 
61     for (int y = 0; y < N; ++y) {
62         for (int x = 0; x < N; ++x) {
63             *bm.getAddr32(x, y) = (x ^ y) & 1 ? 0xFFFFFFFF : 0xFF000000;
64         }
65     }
66     bm.setImmutable();
67     return SkImage::MakeFromBitmap(bm);
68 }
69 
70 static void show_mips(SkCanvas* canvas, SkImage* img) {
71     SkPaint paint;
72     paint.setFilterQuality(kMedium_SkFilterQuality);
73 
74     // Want to ensure we never draw fractional pixels, so we use an IRect
75     SkIRect dst = SkIRect::MakeWH(img->width(), img->height());
76     while (dst.width() > 5) {
77         canvas->drawImageRect(img, SkRect::Make(dst), &paint);
78         dst.offset(dst.width() + 10, 0);
79         dst.fRight = dst.fLeft + dst.width()/2;
80         dst.fBottom = dst.fTop + dst.height()/2;
81     }
82 }
83 
84 /*
85  *  Ensure that in L32 drawing mode, both images/mips look the same as each other, and
86  *  their mips are darker than the original (since the mips should ignore the gamma in L32).
87  *
88  *  Ensure that in S32 drawing mode, all images/mips look the same, and look correct (i.e.
89  *  the mip levels match the original in brightness).
90  */
91 DEF_SIMPLE_GM(mipmap_srgb, canvas, 260, 230) {
92     sk_sp<SkImage> limg = make(nullptr);
93     sk_sp<SkImage> simg = make(SkColorSpace::MakeSRGB());
94 
95     canvas->translate(10, 10);
96     show_mips(canvas, limg.get());
97     canvas->translate(0, limg->height() + 10.0f);
98     show_mips(canvas, simg.get());
99 }
100 
101 ///////////////////////////////////////////////////////////////////////////////////////////////////
102 
103 // create a gradient image computed raw, so we can wrap it as a linear or srgb image
104 static sk_sp<SkImage> make_g8_gradient(sk_sp<SkColorSpace> cs) {
105     const int N = 100;
106     SkImageInfo info = SkImageInfo::Make(N, N, kGray_8_SkColorType, kOpaque_SkAlphaType, cs);
107     SkBitmap bm;
108     bm.allocPixels(info);
109 
110     for (int y = 0; y < N; ++y) {
111         for (int x = 0; x < N; ++x) {
112             *bm.getAddr8(x, y) = static_cast<uint8_t>(255.0f * ((x + y) / (2.0f * (N - 1))));
113         }
114     }
115     bm.setImmutable();
116     return SkImage::MakeFromBitmap(bm);
117 }
118 
119 static void show_mips_only(SkCanvas* canvas, SkImage* img) {
120     SkPaint paint;
121     paint.setFilterQuality(kMedium_SkFilterQuality);
122 
123     // Want to ensure we never draw fractional pixels, so we use an IRect
124     SkIRect dst = SkIRect::MakeWH(img->width() / 2, img->height() / 2);
125     while (dst.width() > 5) {
126         canvas->drawImageRect(img, SkRect::Make(dst), &paint);
127         dst.offset(dst.width() + 10, 0);
128         dst.fRight = dst.fLeft + dst.width() / 2;
129         dst.fBottom = dst.fTop + dst.height() / 2;
130     }
131 }
132 
133 /*
134  *  Ensure that in L32 drawing mode, both images/mips look the same as each other, and
135  *  their mips are darker than the original (since the mips should ignore the gamma in L32).
136  *
137  *  Ensure that in S32 drawing mode, all images/mips look the same, and look correct (i.e.
138  *  the mip levels match the original in brightness).
139  */
140 DEF_SIMPLE_GM(mipmap_gray8_srgb, canvas, 260, 230) {
141     sk_sp<SkImage> limg = make_g8_gradient(nullptr);
142     sk_sp<SkImage> simg = make_g8_gradient(SkColorSpace::MakeSRGB());
143 
144     canvas->translate(10, 10);
145     show_mips_only(canvas, limg.get());
146     canvas->translate(0, limg->height() + 10.0f);
147     show_mips_only(canvas, simg.get());
148 }
149