1/*
2 * Copyright 2016 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 "SkImageGenerator.h"
13#include "SkMakeUnique.h"
14#include "SkSurface.h"
15
16namespace {
17
18const SkISize   kSize = SkISize::Make(100, 100);
19const SkIRect kSubset = SkIRect::MakeLTRB(25, 25, 75, 75);
20const SkRect    kDest = SkRect::MakeXYWH(10, 10, 100, 100);
21
22sk_sp<SkImage> make_mask(const sk_sp<SkSurface>& surface) {
23    sk_tool_utils::draw_checkerboard(surface->getCanvas(), 0x80808080, 0x00000000, 5);
24    return surface->makeImageSnapshot();
25}
26
27class MaskGenerator final : public SkImageGenerator {
28public:
29    MaskGenerator(const SkImageInfo& info) : INHERITED(info) {}
30
31    bool onGetPixels(const SkImageInfo& info, void* pixels, size_t rowBytes, SkPMColor*,
32                     int*) override {
33        if (info.colorType() == kIndex_8_SkColorType) {
34            return false;
35        }
36
37        SkImageInfo surfaceInfo = info;
38        if (kAlpha_8_SkColorType == info.colorType()) {
39            surfaceInfo = surfaceInfo.makeColorSpace(nullptr);
40        }
41
42        make_mask(SkSurface::MakeRasterDirect(surfaceInfo, pixels, rowBytes));
43        return true;
44    }
45
46private:
47    typedef SkImageGenerator INHERITED;
48};
49
50using MakerT = sk_sp<SkImage>(*)(SkCanvas*, const SkImageInfo&);
51const MakerT makers[] = {
52    // SkImage_Raster
53    [](SkCanvas*, const SkImageInfo& info) -> sk_sp<SkImage> {
54        return make_mask(SkSurface::MakeRaster(info));
55    },
56
57    // SkImage_Gpu
58    [](SkCanvas* c, const SkImageInfo& info) -> sk_sp<SkImage> {
59        sk_sp<SkSurface> surface;
60#if SK_SUPPORT_GPU
61        surface = SkSurface::MakeRenderTarget(c->getGrContext(), SkBudgeted::kNo, info);
62#endif
63        return make_mask(surface ? surface : SkSurface::MakeRaster(info));
64    },
65
66    // SkImage_Generator
67    [](SkCanvas*, const SkImageInfo& info) -> sk_sp<SkImage> {
68        return SkImage::MakeFromGenerator(skstd::make_unique<MaskGenerator>(info));
69    },
70};
71
72} // anonymous ns
73
74// Checks whether subset SkImages preserve the original color type (A8 in this case).
75DEF_SIMPLE_GM(imagemasksubset, canvas, 480, 480) {
76    SkPaint paint;
77    paint.setColor(0xff00ff00);
78
79    const SkImageInfo info = SkImageInfo::MakeA8(kSize.width(), kSize.height());
80
81    for (size_t i = 0; i < SK_ARRAY_COUNT(makers); ++i) {
82        sk_sp<SkImage> image = makers[i](canvas, info);
83        if (image) {
84            canvas->drawImageRect(image, SkRect::Make(kSubset), kDest, &paint);
85            sk_sp<SkImage> subset = image->makeSubset(kSubset);
86            canvas->drawImageRect(subset, kDest.makeOffset(kSize.width() * 1.5f, 0), &paint);
87        }
88        canvas->translate(0, kSize.height() * 1.5f);
89    }
90}
91