TimingSlide Class Reference

Inheritance diagram for TimingSlide:

Public Member Functions
	TimingSlide ()
void	load (SkScalar w, SkScalar h) override
void	draw (SkCanvas *canvas) override
Public Member Functions inherited from Slide
virtual SkISize	getDimensions () const
virtual void	gpuTeardown ()
virtual bool	animate (double nanos)
virtual void	resize (SkScalar winWidth, SkScalar winHeight)
virtual void	unload ()
virtual bool	onChar (SkUnichar c)
virtual bool	onMouse (SkScalar x, SkScalar y, skui::InputState state, skui::ModifierKey modifiers)
virtual bool	onGetControls (SkMetaData *)
virtual void	onSetControls (const SkMetaData &)
const SkString &	getName ()
Public Member Functions inherited from SkRefCntBase
	SkRefCntBase ()
virtual	~SkRefCntBase ()
bool	unique () const
void	ref () const
void	unref () const

Additional Inherited Members
Protected Attributes inherited from Slide
SkString	fName

Detailed Description

Definition at line 16 of file TimingSlide.cpp.

Constructor & Destructor Documentation

TimingSlide()

TimingSlide::TimingSlide ( )

inline

Definition at line 18 of file TimingSlide.cpp.

{ fName = "Timing";}

Member Function Documentation

draw()

void TimingSlide::draw ( SkCanvas *  canvas )

inlineoverridevirtual

Implements Slide.

Definition at line 26 of file TimingSlide.cpp.

                                         {
        canvas->scale(8,8);
 
        // Draw normally.
        canvas->drawImage(fImg, 0,0);
 
        canvas->translate(0,H);
 
        // Draw one pixel at a time with drawImageRect(),
        // timing how long each drawImageRect() call takes.
        double cost[H][W];
        double min = +INFINITY,
               max = -INFINITY;
        for (int y = 0; y < H; y++)
        for (int x = 0; x < W; x++) {
            auto start = std::chrono::steady_clock::now();
            canvas->drawImageRect(fImg.get(),
                                  SkRect::MakeXYWH(x,y,1,1), SkRect::MakeXYWH(x,y,1,1),
                                  SkSamplingOptions(), /*paint=*/nullptr,
                                  SkCanvas::kStrict_SrcRectConstraint);
            auto elapsed = std::chrono::steady_clock::now() - start;
 
            cost[y][x] = elapsed.count();
            min = std::min(min, cost[y][x]);
            max = std::max(max, cost[y][x]);
        }
 
        canvas->translate(0,H);
 
        // Draw using those per-pixel timings,
        // with the slowest pixel scaled to alpha=1, the fastest to alpha=0.
        for (int y = 0; y < H; y++)
        for (int x = 0; x < W; x++) {
            SkPaint p;
            p.setAlphaf( (cost[y][x] - min) / (max - min) );
            canvas->drawRect(SkRect::MakeXYWH(x,y,1,1), p);
        }
 
        canvas->translate(0,H);
 
        // Draw each pixel into offscreen, timing each draw.
        SkImageInfo info = canvas->imageInfo().makeWH(1024,1024);
        if (sk_sp<SkSurface> offscreen = canvas->makeSurface(info)) {
            min = +INFINITY;
            max = -INFINITY;
            for (int y = 0; y < H; y++)
            for (int x = 0; x < W; x++) {
                auto start = std::chrono::steady_clock::now();
                offscreen->getCanvas()->drawImageRect(fImg,
                                                      SkRect::MakeXYWH(x,y,1,1),
                                                      SkRect::MakeXYWH(0,0,1024,1024),
                                                      SkSamplingOptions(),
                                                      /*paint=*/nullptr,
                                                      SkCanvas::kStrict_SrcRectConstraint);
                auto elapsed = std::chrono::steady_clock::now() - start;
 
                cost[y][x] = elapsed.count();
                min = std::min(min, cost[y][x]);
                max = std::max(max, cost[y][x]);
            }
            for (int y = 0; y < H; y++)
            for (int x = 0; x < W; x++) {
                SkPaint p;
                p.setAlphaf( (cost[y][x] - min) / (max - min) );
                canvas->drawRect(SkRect::MakeXYWH(x,y,1,1), p);
            }
        }
    }

load()

void TimingSlide::load ( SkScalar  w, SkScalar  h  )

inlineoverridevirtual

Reimplemented from Slide.

Definition at line 20 of file TimingSlide.cpp.

                                               {
        sk_sp<SkSurface> surf = SkSurfaces::Raster(SkImageInfo::MakeN32Premul(W, H));
        surf->getCanvas()->drawString("abc", 2,H-4, ToolUtils::DefaultFont(), SkPaint{});
        fImg = surf->makeImageSnapshot();
    }

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The documentation for this class was generated from the following file:

• third_party/skia/tools/viewer/TimingSlide.cpp