text: /*
   * Copyright 2011 Google Inc.
   *
   * Use of this source code is governed by a BSD-style license that can be
   * found in the LICENSE file.
   */
  
  #include <functional>
  #include "gm.h"
  #include "SkData.h"
  #include "SkCanvas.h"
  #include "SkRandom.h"
  #include "SkStream.h"
  #include "SkSurface.h"
  
  #if SK_SUPPORT_GPU
  #include "GrContext.h"
  #endif
  
  static void drawJpeg(SkCanvas* canvas, const SkISize& size) {
      // TODO: Make this draw a file that is checked in, so it can
      // be exercised on machines other than mike's. Will require a
      // rebaseline.
      SkAutoDataUnref data(SkData::NewFromFileName("/Users/mike/Downloads/skia.google.jpeg"));
      if (nullptr == data.get()) {
          return;
      }
      SkImage* image = SkImage::NewFromEncoded(data);
      if (image) {
          SkAutoCanvasRestore acr(canvas, true);
          canvas->scale(size.width() * 1.0f / image->width(),
                        size.height() * 1.0f / image->height());
          canvas->drawImage(image, 0, 0, nullptr);
          image->unref();
      }
  }
  
  static void drawContents(SkSurface* surface, SkColor fillC) {
      SkSize size = SkSize::Make(SkIntToScalar(surface->width()),
                                 SkIntToScalar(surface->height()));
      SkCanvas* canvas = surface->getCanvas();
  
      SkScalar stroke = size.fWidth / 10;
      SkScalar radius = (size.fWidth - stroke) / 2;
  
      SkPaint paint;
  
      paint.setAntiAlias(true);
      paint.setColor(fillC);
      canvas->drawCircle(size.fWidth/2, size.fHeight/2, radius, paint);
  
      paint.setStyle(SkPaint::kStroke_Style);
      paint.setStrokeWidth(stroke);
      paint.setColor(SK_ColorBLACK);
      canvas->drawCircle(size.fWidth/2, size.fHeight/2, radius, paint);
  }
  
  static void test_surface(SkCanvas* canvas, SkSurface* surf, bool usePaint) {
      drawContents(surf, SK_ColorRED);
      SkImage* imgR = surf->newImageSnapshot();
  
      if (true) {
          SkImage* imgR2 = surf->newImageSnapshot();
          SkASSERT(imgR == imgR2);
          imgR2->unref();
      }
  
      drawContents(surf, SK_ColorGREEN);
      SkImage* imgG = surf->newImageSnapshot();
  
      // since we've drawn after we snapped imgR, imgG will be a different obj
      SkASSERT(imgR != imgG);
  
      drawContents(surf, SK_ColorBLUE);
  
      SkPaint paint;
  //    paint.setFilterBitmap(true);
  //    paint.setAlpha(0x80);
  
      canvas->drawImage(imgR, 0, 0, usePaint ? &paint : nullptr);
      canvas->drawImage(imgG, 0, 80, usePaint ? &paint : nullptr);
      surf->draw(canvas, 0, 160, usePaint ? &paint : nullptr);
  
      SkRect src1, src2, src3;
      src1.iset(0, 0, surf->width(), surf->height());
      src2.iset(-surf->width() / 2, -surf->height() / 2,
               surf->width(), surf->height());
      src3.iset(0, 0, surf->width() / 2, surf->height() / 2);
  
      SkRect dst1, dst2, dst3, dst4;
      dst1.set(0, 240, 65, 305);
      dst2.set(0, 320, 65, 385);
      dst3.set(0, 400, 65, 465);
      dst4.set(0, 480, 65, 545);
  
      canvas->drawImageRect(imgR, src1, dst1, usePaint ? &paint : nullptr);
      canvas->drawImageRect(imgG, src2, dst2, usePaint ? &paint : nullptr);
      canvas->drawImageRect(imgR, src3, dst3, usePaint ? &paint : nullptr);
      canvas->drawImageRect(imgG, dst4, usePaint ? &paint : nullptr);
  
      imgG->unref();
      imgR->unref();
  }
  
  class ImageGM : public skiagm::GM {
      void*   fBuffer;
      size_t  fBufferSize;
      SkSize  fSize;
      enum {
          W = 64,
          H = 64,
          RB = W * 4 + 8,
      };
  public:
      ImageGM() {
          fBufferSize = RB * H;
          fBuffer = sk_malloc_throw(fBufferSize);
          fSize.set(SkIntToScalar(W), SkIntToScalar(H));
      }
  
      virtual ~ImageGM() {
          sk_free(fBuffer);
      }
  
  protected:
      SkString onShortName() override {
          return SkString("image-surface");
      }
  
      SkISize onISize() override {
          return SkISize::Make(960, 1200);
      }
  
      void onDraw(SkCanvas* canvas) override {
          drawJpeg(canvas, this->getISize());
  
          canvas->scale(2, 2);
  
          static const char* kLabel1 = "Original Img";
          static const char* kLabel2 = "Modified Img";
          static const char* kLabel3 = "Cur Surface";
          static const char* kLabel4 = "Full Crop";
          static const char* kLabel5 = "Over-crop";
          static const char* kLabel6 = "Upper-left";
          static const char* kLabel7 = "No Crop";
  
          static const char* kLabel8 = "Pre-Alloc Img";
          static const char* kLabel9 = "New Alloc Img";
          static const char* kLabel10 = "GPU";
  
          SkPaint textPaint;
          textPaint.setAntiAlias(true);
          sk_tool_utils::set_portable_typeface(&textPaint);
          textPaint.setTextSize(8);
  
          canvas->drawText(kLabel1, strlen(kLabel1), 10,  60, textPaint);
          canvas->drawText(kLabel2, strlen(kLabel2), 10, 140, textPaint);
          canvas->drawText(kLabel3, strlen(kLabel3), 10, 220, textPaint);
          canvas->drawText(kLabel4, strlen(kLabel4), 10, 300, textPaint);
          canvas->drawText(kLabel5, strlen(kLabel5), 10, 380, textPaint);
          canvas->drawText(kLabel6, strlen(kLabel6), 10, 460, textPaint);
          canvas->drawText(kLabel7, strlen(kLabel7), 10, 540, textPaint);
  
          canvas->drawText(kLabel8, strlen(kLabel8),  80, 10, textPaint);
          canvas->drawText(kLabel9, strlen(kLabel9), 160, 10, textPaint);
          canvas->drawText(kLabel10, strlen(kLabel10), 265, 10, textPaint);
  
          canvas->translate(80, 20);
  
          // since we draw into this directly, we need to start fresh
          sk_bzero(fBuffer, fBufferSize);
  
          SkImageInfo info = SkImageInfo::MakeN32Premul(W, H);
          SkAutoTUnref<SkSurface> surf0(SkSurface::NewRasterDirect(info, fBuffer, RB));
          SkAutoTUnref<SkSurface> surf1(SkSurface::NewRaster(info));
          SkAutoTUnref<SkSurface> surf2;  // gpu
  
  #if SK_SUPPORT_GPU
          surf2.reset(SkSurface::NewRenderTarget(canvas->getGrContext(),
                                                 SkBudgeted::kNo, info));
  #endif
  
          test_surface(canvas, surf0, true);
          canvas->translate(80, 0);
          test_surface(canvas, surf1, true);
          if (surf2) {
              canvas->translate(80, 0);
              test_surface(canvas, surf2, true);
          }
      }
  
  private:
      typedef skiagm::GM INHERITED;
  };
  DEF_GM( return new ImageGM; )
  
  ///////////////////////////////////////////////////////////////////////////////////////////////////
  
  #include "SkPictureRecorder.h"
  
  static void draw_pixmap(SkCanvas* canvas, const SkPixmap& pmap) {
      SkBitmap bitmap;
      bitmap.installPixels(pmap);
      canvas->drawBitmap(bitmap, 0, 0, nullptr);
  }
  
  static void show_scaled_pixels(SkCanvas* canvas, SkImage* image) {
      SkAutoCanvasRestore acr(canvas, true);
  
      canvas->drawImage(image, 0, 0, nullptr);
      canvas->translate(110, 10);
  
      const SkImageInfo info = SkImageInfo::MakeN32Premul(40, 40);
      SkAutoPixmapStorage storage;
      storage.alloc(info);
  
      const SkImage::CachingHint chints[] = {
          SkImage::kAllow_CachingHint, SkImage::kDisallow_CachingHint,
      };
      const SkFilterQuality qualities[] = {
          kNone_SkFilterQuality, kLow_SkFilterQuality, kMedium_SkFilterQuality, kHigh_SkFilterQuality,
      };
  
      for (auto ch : chints) {
          canvas->save();
          for (auto q : qualities) {
              if (image->scalePixels(storage, q, ch)) {
                  draw_pixmap(canvas, storage);
              }
              canvas->translate(70, 0);
          }
          canvas->restore();
          canvas->translate(0, 45);
      }
  }
  
  static void draw_contents(SkCanvas* canvas) {
      SkPaint paint;
      paint.setStyle(SkPaint::kStroke_Style);
      paint.setStrokeWidth(20);
      canvas->drawCircle(50, 50, 35, paint);
  }
  
  static SkImage* make_raster(const SkImageInfo& info, GrContext*, void (*draw)(SkCanvas*)) {
      SkAutoTUnref<SkSurface> surface(SkSurface::NewRaster(info));
      draw(surface->getCanvas());
      return surface->newImageSnapshot();
  }
  
  static SkImage* make_picture(const SkImageInfo& info, GrContext*, void (*draw)(SkCanvas*)) {
      SkPictureRecorder recorder;
      draw(recorder.beginRecording(SkRect::MakeIWH(info.width(), info.height())));
      SkAutoTUnref<SkPicture> pict(recorder.endRecording());
      return SkImage::NewFromPicture(pict, info.dimensions(), nullptr, nullptr);
  }
  
  static SkImage* make_codec(const SkImageInfo& info, GrContext*, void (*draw)(SkCanvas*)) {
      SkAutoTUnref<SkImage> image(make_raster(info, nullptr, draw));
      SkAutoTUnref<SkData> data(image->encode());
      return SkImage::NewFromEncoded(data);
  }
  
  static SkImage* make_gpu(const SkImageInfo& info, GrContext* ctx, void (*draw)(SkCanvas*)) {
      if (!ctx) { return nullptr; }
      SkAutoTUnref<SkSurface> surface(SkSurface::NewRenderTarget(ctx, SkBudgeted::kNo, info));
      draw(surface->getCanvas());
      return surface->newImageSnapshot();
  }
  
  typedef SkImage* (*ImageMakerProc)(const SkImageInfo&, GrContext*, void (*)(SkCanvas*));
  
  class ScalePixelsGM : public skiagm::GM {
  public:
      ScalePixelsGM() {}
  
  protected:
      SkString onShortName() override {
          return SkString("scale-pixels");
      }
  
      SkISize onISize() override {
          return SkISize::Make(960, 1200);
      }
  
      void onDraw(SkCanvas* canvas) override {
          const SkImageInfo info = SkImageInfo::MakeN32Premul(100, 100);
  
          const ImageMakerProc procs[] = {
              make_codec, make_raster, make_picture, make_codec, make_gpu,
          };
          for (auto& proc : procs) {
              SkAutoTUnref<SkImage> image(proc(info, canvas->getGrContext(), draw_contents));
              if (image) {
                  show_scaled_pixels(canvas, image);
              }
              canvas->translate(0, 120);
          }
      }
      
  private:
      typedef skiagm::GM INHERITED;
  };
  DEF_GM( return new ScalePixelsGM; )
  
  ///////////////////////////////////////////////////////////////////////////////////////////////////
  
  #include "SkImageGenerator.h"
  
  static SkImageInfo make_info(SkImage* img) {
      return SkImageInfo::MakeN32(img->width(), img->height(),
                                  img->isOpaque() ? kOpaque_SkAlphaType : kPremul_SkAlphaType);
  }
  
  // Its simple, but I wonder if we should expose this formally?
  //
  class ImageGeneratorFromImage : public SkImageGenerator {
  public:
      ImageGeneratorFromImage(SkImage* img) : INHERITED(make_info(img)), fImg(SkRef(img)) {}
  
  protected:
      bool onGetPixels(const SkImageInfo& info, void* pixels, size_t rowBytes, SkPMColor ctable[],
                       int* ctableCount) override {
          return fImg->readPixels(info, pixels, rowBytes, 0, 0);
      }
  
  private:
      SkAutoTUnref<SkImage> fImg;
  
      typedef SkImageGenerator INHERITED;
  };
  
  static void draw_opaque_contents(SkCanvas* canvas) {
      canvas->drawColor(0xFFFF8844);
  
      SkPaint paint;
      paint.setStyle(SkPaint::kStroke_Style);
      paint.setStrokeWidth(20);
      canvas->drawCircle(50, 50, 35, paint);
  }
  
  static SkImageGenerator* gen_raster(const SkImageInfo& info) {
      SkAutoTUnref<SkSurface> surface(SkSurface::NewRaster(info));
      draw_opaque_contents(surface->getCanvas());
      SkAutoTUnref<SkImage> img(surface->newImageSnapshot());
      return new ImageGeneratorFromImage(img);
  }
  
  static SkImageGenerator* gen_picture(const SkImageInfo& info) {
      SkPictureRecorder recorder;
      draw_opaque_contents(recorder.beginRecording(SkRect::MakeIWH(info.width(), info.height())));
      SkAutoTUnref<SkPicture> pict(recorder.endRecording());
      return SkImageGenerator::NewFromPicture(info.dimensions(), pict, nullptr, nullptr);
  }
  
  static SkImageGenerator* gen_png(const SkImageInfo& info) {
      SkAutoTUnref<SkImage> image(make_raster(info, nullptr, draw_opaque_contents));
      SkAutoTUnref<SkData> data(image->encode(SkImageEncoder::kPNG_Type, 100));
      return SkImageGenerator::NewFromEncoded(data);
  }
  
  static SkImageGenerator* gen_jpg(const SkImageInfo& info) {
      SkAutoTUnref<SkImage> image(make_raster(info, nullptr, draw_opaque_contents));
      SkAutoTUnref<SkData> data(image->encode(SkImageEncoder::kJPEG_Type, 100));
      return SkImageGenerator::NewFromEncoded(data);
  }
  
  typedef SkImageGenerator* (*GeneratorMakerProc)(const SkImageInfo&);
  
  static void show_scaled_generator(SkCanvas* canvas, SkImageGenerator* gen) {
      const SkImageInfo genInfo = gen->getInfo();
  
      SkAutoCanvasRestore acr(canvas, true);
  
      SkBitmap bm;
      bm.allocPixels(genInfo);
      if (gen->getPixels(bm.info(), bm.getPixels(), bm.rowBytes())) {
          canvas->drawBitmap(bm, 0, 0, nullptr);
      }
      canvas->translate(110, 0);
  
      const float scales[] = { 0.75f, 0.5f, 0.25f };
      for (auto scale : scales) {
          SkImageGenerator::SupportedSizes sizes;
          if (gen->computeScaledDimensions(scale, &sizes)) {
              const SkImageInfo info = SkImageInfo::MakeN32Premul(sizes.fSizes[0].width(),
                                                                  sizes.fSizes[0].height());
              bm.allocPixels(info);
              SkPixmap pmap;
              bm.peekPixels(&pmap);
              if (gen->generateScaledPixels(pmap)) {
                  canvas->drawBitmap(bm, 0, SkIntToScalar(genInfo.height() - info.height())/2);
              }
          }
          canvas->translate(100, 0);
      }
  }
  
  class ScaleGeneratorGM : public skiagm::GM {
  public:
      ScaleGeneratorGM() {}
  
  protected:
      SkString onShortName() override {
          return SkString("scale-generator");
      }
  
      SkISize onISize() override {
          return SkISize::Make(500, 500);
      }
  
      void onDraw(SkCanvas* canvas) override {
          canvas->translate(10, 10);
  
          // explicitly make it opaque, so we can test JPEG (which is only ever opaque)
          const SkImageInfo info = SkImageInfo::MakeN32(100, 100, kOpaque_SkAlphaType);
  
          const GeneratorMakerProc procs[] = {
              gen_raster, gen_picture, gen_png, gen_jpg,
          };
          for (auto& proc : procs) {
              SkAutoTDelete<SkImageGenerator> gen(proc(info));
              if (gen) {
                  show_scaled_generator(canvas, gen);
              }
              canvas->translate(0, 120);
          }
      }
  
  private:
      typedef skiagm::GM INHERITED;
  };
  DEF_GM( return new ScaleGeneratorGM; )
  
  #if SK_SUPPORT_GPU
  #include "GrContextFactory.h"
  #endif
  
  DEF_SIMPLE_GM(new_texture_image, canvas, 225, 60) {
      GrContext* context = nullptr;
  #if SK_SUPPORT_GPU
      context = canvas->getGrContext();
      GrContextFactory factory;
  #endif
      if (!context) {
          skiagm::GM::DrawGpuOnlyMessage(canvas);
          return;
      }
  
      auto render_image = [](SkCanvas* canvas) {
          canvas->clear(SK_ColorBLUE);
          SkPaint paint;
          paint.setColor(SK_ColorRED);
          canvas->drawRect(SkRect::MakeXYWH(10.f,10.f,10.f,10.f), paint);
          paint.setColor(SK_ColorGREEN);
          canvas->drawRect(SkRect::MakeXYWH(30.f,10.f,10.f,10.f), paint);
          paint.setColor(SK_ColorYELLOW);
          canvas->drawRect(SkRect::MakeXYWH(10.f,30.f,10.f,10.f), paint);
          paint.setColor(SK_ColorCYAN);
          canvas->drawRect(SkRect::MakeXYWH(30.f,30.f,10.f,10.f), paint);
      };
  
      static const int kSize = 50;
      SkBitmap bmp;
      bmp.allocN32Pixels(kSize, kSize);
      SkCanvas bmpCanvas(bmp);
      render_image(&bmpCanvas);
  
      std::function<SkImage*()> imageFactories[] = {
          // Create sw raster image.
          [bmp] {
              return SkImage::NewFromBitmap(bmp);
          },
          // Create encoded image.
          [bmp] {
              SkAutoTUnref<SkData> src(
                  SkImageEncoder::EncodeData(bmp, SkImageEncoder::kPNG_Type, 100));
              return SkImage::NewFromEncoded(src);
          },
          // Create a picture image.
          [render_image] {
              SkPictureRecorder recorder;
              SkCanvas* canvas = recorder.beginRecording(SkIntToScalar(kSize), SkIntToScalar(kSize));
              render_image(canvas);
              SkAutoTUnref<SkPicture> picture(recorder.endRecording());
              return SkImage::NewFromPicture(picture, SkISize::Make(kSize, kSize), nullptr, nullptr);
          },
          // Create a texture image
          [context, render_image]() -> SkImage* {
              SkAutoTUnref<SkSurface> surface(
                  SkSurface::NewRenderTarget(context, SkBudgeted::kYes,
                                             SkImageInfo::MakeN32Premul(kSize, kSize)));
              if (!surface) {
                  return nullptr;
              }
              render_image(surface->getCanvas());
              return surface->newImageSnapshot();
          }
      };
  
      static const SkScalar kPad = 5.f;
      canvas->translate(kPad, kPad);
      for (auto factory : imageFactories) {
          SkAutoTUnref<SkImage> image(factory());
          if (!image) {
              continue;
          }
          if (context) {
              SkAutoTUnref<SkImage> texImage(image->newTextureImage(context));
              if (texImage) {
                  canvas->drawImage(texImage, 0, 0);
              }
          }
          canvas->translate(image->width() + kPad, 0);
      }
  }
  