submodule/skia/gm/image_shader.cpp

   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/gm.h"
   9 #include "include/core/SkBitmap.h"
  10 #include "include/core/SkCanvas.h"
  11 #include "include/core/SkColor.h"
  12 #include "include/core/SkColorSpace.h"
  13 #include "include/core/SkData.h"
  14 #include "include/core/SkEncodedImageFormat.h"
  15 #include "include/core/SkImage.h"
  16 #include "include/core/SkImageInfo.h"
  17 #include "include/core/SkMatrix.h"
  18 #include "include/core/SkPaint.h"
  19 #include "include/core/SkPicture.h"
  20 #include "include/core/SkPictureRecorder.h"
  21 #include "include/core/SkRect.h"
  22 #include "include/core/SkRefCnt.h"
  23 #include "include/core/SkShader.h"
  24 #include "include/core/SkSize.h"
  25 #include "include/core/SkString.h"
  26 #include "include/core/SkSurface.h"
  27 #include "include/core/SkTileMode.h"
  28 #include "include/core/SkTypes.h"
  29
  30 #include <utility>
  31
  32 static void draw_something(SkCanvas* canvas, const SkRect& bounds) {
  33     SkPaint paint;
  34     paint.setAntiAlias(true);
  35     paint.setColor(SK_ColorRED);
  36     paint.setStyle(SkPaint::kStroke_Style);
  37     paint.setStrokeWidth(10);
  38     canvas->drawRect(bounds, paint);
  39     paint.setStyle(SkPaint::kFill_Style);
  40     paint.setColor(SK_ColorBLUE);
  41     canvas->drawOval(bounds, paint);
  42 }
  43
  44 typedef sk_sp<SkImage> (*ImageMakerProc)(GrRecordingContext*, SkPicture*, const SkImageInfo&);
  45
  46 static sk_sp<SkImage> make_raster(GrRecordingContext*,
  47                                   SkPicture* pic,
  48                                   const SkImageInfo& info) {
  49     auto surface(SkSurface::MakeRaster(info));
  50     surface->getCanvas()->clear(0);
  51     surface->getCanvas()->drawPicture(pic);
  52     return surface->makeImageSnapshot();
  53 }
  54
  55 static sk_sp<SkImage> make_texture(GrRecordingContext* ctx,
  56                                    SkPicture* pic,
  57                                    const SkImageInfo& info) {
  58     if (!ctx) {
  59         return nullptr;
  60     }
  61     auto surface(SkSurface::MakeRenderTarget(ctx, SkBudgeted::kNo, info));
  62     if (!surface) {
  63         return nullptr;
  64     }
  65     surface->getCanvas()->clear(0);
  66     surface->getCanvas()->drawPicture(pic);
  67     return surface->makeImageSnapshot();
  68 }
  69
  70 static sk_sp<SkImage> make_pict_gen(GrRecordingContext*,
  71                                     SkPicture* pic,
  72                                     const SkImageInfo& info) {
  73     return SkImage::MakeFromPicture(sk_ref_sp(pic), info.dimensions(), nullptr, nullptr,
  74                                     SkImage::BitDepth::kU8,
  75                                     SkColorSpace::MakeSRGB());
  76 }
  77
  78 static sk_sp<SkImage> make_encode_gen(GrRecordingContext* ctx,
  79                                       SkPicture* pic,
  80                                       const SkImageInfo& info) {
  81     sk_sp<SkImage> src(make_raster(ctx, pic, info));
  82     if (!src) {
  83         return nullptr;
  84     }
  85     sk_sp<SkData> encoded = src->encodeToData(SkEncodedImageFormat::kPNG, 100);
  86     if (!encoded) {
  87         return nullptr;
  88     }
  89     return SkImage::MakeFromEncoded(std::move(encoded));
  90 }
  91
  92 const ImageMakerProc gProcs[] = {
  93     make_raster,
  94     make_texture,
  95     make_pict_gen,
  96     make_encode_gen,
  97 };
  98
  99 /*
 100  *  Exercise drawing pictures inside an image, showing that the image version is pixelated
 101  *  (correctly) when it is inside an image.
 102  */
 103 class ImageShaderGM : public skiagm::GM {
 104     sk_sp<SkPicture> fPicture;
 105
 106 public:
 107     ImageShaderGM() {}
 108
 109 protected:
 110     SkString onShortName() override {
 111         return SkString("image-shader");
 112     }
 113
 114     SkISize onISize() override {
 115         return SkISize::Make(850, 450);
 116     }
 117
 118     void onOnceBeforeDraw() override {
 119         const SkRect bounds = SkRect::MakeWH(100, 100);
 120         SkPictureRecorder recorder;
 121         draw_something(recorder.beginRecording(bounds), bounds);
 122         fPicture = recorder.finishRecordingAsPicture();
 123     }
 124
 125     void testImage(SkCanvas* canvas, SkImage* image) {
 126         SkAutoCanvasRestore acr(canvas, true);
 127
 128         canvas->drawImage(image, 0, 0);
 129         canvas->translate(0, 120);
 130
 131         const SkTileMode tile = SkTileMode::kRepeat;
 132         const SkMatrix localM = SkMatrix::Translate(-50, -50);
 133         SkPaint paint;
 134         paint.setShader(image->makeShader(tile, tile, SkSamplingOptions(), &localM));
 135         paint.setAntiAlias(true);
 136         canvas->drawCircle(50, 50, 50, paint);
 137     }
 138
 139     void onDraw(SkCanvas* canvas) override {
 140         canvas->translate(20, 20);
 141
 142         const SkImageInfo info = SkImageInfo::MakeN32Premul(100, 100);
 143
 144         for (size_t i = 0; i < SK_ARRAY_COUNT(gProcs); ++i) {
 145             sk_sp<SkImage> image(gProcs[i](canvas->recordingContext(), fPicture.get(), info));
 146             if (image) {
 147                 this->testImage(canvas, image.get());
 148             }
 149             canvas->translate(120, 0);
 150         }
 151     }
 152
 153 private:
 154     using INHERITED = skiagm::GM;
 155 };
 156 DEF_GM( return new ImageShaderGM; )
 157
 158 //////////////////////////////////////////////////////////////////////////////////////////////
 159
 160 #include "tools/ToolUtils.h"
 161
 162 static sk_sp<SkImage> make_checker_img(int w, int h, SkColor c0, SkColor c1, int size) {
 163     SkBitmap bm = ToolUtils::create_checkerboard_bitmap(w, h, c0, c1, size);
 164     bm.setImmutable();
 165     return bm.asImage();
 166 }
 167
 168 DEF_SIMPLE_GM(drawimage_sampling, canvas, 500, 500) {
 169     constexpr int N = 256;
 170     constexpr float kScale = 1.0f/6;
 171     const SkRect dst = {0, 0, kScale*N, kScale*N};
 172
 173     auto img = make_checker_img(N, N, SK_ColorBLACK, SK_ColorWHITE, 7)->withDefaultMipmaps();
 174     const SkRect src = SkRect::MakeIWH(img->width(), img->height());
 175
 176     SkMatrix mx = SkMatrix::RectToRect(src, dst);
 177
 178     SkPaint paint;
 179
 180     for (auto mm : {SkMipmapMode::kNone, SkMipmapMode::kNearest, SkMipmapMode::kLinear}) {
 181         for (auto fm : {SkFilterMode::kNearest, SkFilterMode::kLinear}) {
 182             SkSamplingOptions sampling(fm, mm);
 183
 184             canvas->save();
 185
 186             canvas->save();
 187             canvas->concat(mx);
 188             canvas->drawImage(img.get(), 0, 0, sampling);
 189             canvas->restore();
 190
 191             canvas->translate(dst.width() + 4, 0);
 192
 193             paint.setShader(img->makeShader(SkTileMode::kClamp, SkTileMode::kClamp, sampling, &mx));
 194             canvas->drawRect(dst, paint);
 195
 196             canvas->translate(dst.width() + 4, 0);
 197
 198             canvas->drawImageRect(img.get(), src, dst, sampling, nullptr,
 199                                   SkCanvas::kFast_SrcRectConstraint);
 200             canvas->restore();
 201
 202             canvas->translate(0, dst.height() + 8);
 203         }
 204     }
 205
 206 }
 207
 208 // Test case for skbug.com/12685 (texture-backed image shaders silently fail drawing to CPU canvas)
 209 DEF_SIMPLE_GM(textureimage_and_shader, canvas, 100, 50) {
 210     canvas->clear(SK_ColorGREEN);
 211
 212     sk_sp<SkImage> image;
 213     if (canvas->getSurface()) {
 214         image = canvas->getSurface()->makeImageSnapshot();
 215         canvas->clear(SK_ColorRED);
 216     } else {
 217         auto greenSurface = SkSurface::MakeRasterN32Premul(50, 50);
 218         greenSurface->getCanvas()->clear(SK_ColorGREEN);
 219         image = greenSurface->makeImageSnapshot();
 220     }
 221
 222     // At this point, 'image' contains a green image. If our original canvas is GPU-backed, then
 223     // the snapped image will be a (GPU) texture. We will try to draw that image to a non-GPU
 224     // surface, to ensure that we get automatic read-back. If all goes well, we will get a pure
 225     // green result. If either draw fails, we'll get red (most likely).
 226
 227     auto surface = SkSurface::MakeRasterN32Premul(50, 50);
 228
 229     // First, use drawImage:
 230     surface->getCanvas()->clear(SK_ColorRED);
 231     surface->getCanvas()->drawImage(image, 0, 0);
 232     canvas->drawImage(surface->makeImageSnapshot(), 0, 0);
 233
 234     // Now, use an image shader:
 235     SkPaint paint;
 236     paint.setShader(image->makeShader(SkSamplingOptions()));
 237     surface->getCanvas()->clear(SK_ColorRED);
 238     surface->getCanvas()->drawPaint(paint);
 239     canvas->drawImage(surface->makeImageSnapshot(), 50, 0);
 240 }