CanvasArc Class Reference

Inheritance diagram for CanvasArc:

Public Member Functions
	CanvasArc (SkRandom *random, SkSize size)
	~CanvasArc () override=default
void	draw (SkCanvas *canvas) override
void	animate (double) override
Public Member Functions inherited from MMObject
virtual	~MMObject ()=default
virtual void	draw (SkCanvas *canvas)=0
virtual void	animate (double)=0

Detailed Description

Definition at line 330 of file MotionMarkSlide.cpp.

Constructor & Destructor Documentation

CanvasArc()

CanvasArc::CanvasArc ( SkRandom *  random, SkSize  size  )

inline

Definition at line 332 of file MotionMarkSlide.cpp.

                                             {
        constexpr float kMaxX = 6;
        constexpr float kMaxY = 3;
 
        const SkColor baseColors[3] = {
            0xff101010, 0xff808080, 0xffc0c0c0
        };
        const SkColor bonusColors[3] = {
            0xffe01040, 0xff10c030, 0xffe05010
        };
        float distanceX = size.fWidth / kMaxX;
        float distanceY = size.fHeight / (kMaxY + 1);
        int randY = random->nextRangeU(0, kMaxY);
        int randX = random->nextRangeU(0, kMaxX - 1 * (randY % 2));
 
        fPoint = SkPoint::Make(distanceX * (randX + (randY % 2) / 2), distanceY * (randY + 0.5f));
 
        fRadius = 20 + std::pow(random->nextF(), 5) * (std::min(distanceX, distanceY) / 1.8f);
        fStartAngle = random->nextRangeF(0, 2*SK_ScalarPI);
        fEndAngle = random->nextRangeF(0, 2*SK_ScalarPI);
        fOmega = (random->nextF() - 0.5f) * 0.3f;
        fCounterclockwise = random->nextBool();
        // The MotionMark code appends a random element from an array and appends it to the color
        // array, then randomly picks from that. We'll just pick that random element and use it
        // if the index is out of bounds for the base color array.
        SkColor bonusColor = bonusColors[(randX + sk_float_ceil2int(randY * 0.5f)) % 3];
        int colorIndex = random->nextRangeU(0, 3);
        fColor = colorIndex == 3 ? bonusColor : baseColors[colorIndex];
        fLineWidth = 1 + std::pow(random->nextF(), 5) * 30;
        fDoStroke = random->nextRangeU(0, 3) != 0;
    }

~CanvasArc()

CanvasArc::~CanvasArc ( )

overridedefault

Member Function Documentation

animate()

void CanvasArc::animate ( double  )

inlineoverridevirtual

Implements MMObject.

Definition at line 392 of file MotionMarkSlide.cpp.

                                    {
        fStartAngle += fOmega;
        fEndAngle += fOmega / 2;
    }

draw()

void CanvasArc::draw ( SkCanvas *  canvas )

inlineoverridevirtual

Implements MMObject.

Definition at line 366 of file MotionMarkSlide.cpp.

                                         {
        SkPaint paint;
        paint.setAntiAlias(true);
        paint.setColor(fColor);
        SkRect arcRect = SkRect::MakeXYWH(fPoint.fX - fRadius, fPoint.fY - fRadius,
                                          2*fRadius, 2*fRadius);
 
        float startAngleDeg = fStartAngle * 180.f / SK_ScalarPI;
        float endAngleDeg = fEndAngle * 180.f / SK_ScalarPI;
        canonicalize_angle(&startAngleDeg, &endAngleDeg);
        endAngleDeg = adjust_end_angle(startAngleDeg, endAngleDeg, fCounterclockwise);
 
        float sweepAngle = startAngleDeg - endAngleDeg;
 
        if (fDoStroke) {
            paint.setStrokeWidth(fLineWidth);
            paint.setStyle(SkPaint::kStroke_Style);
            canvas->drawArc(arcRect, startAngleDeg, sweepAngle, false, paint);
        } else {
            paint.setStyle(SkPaint::kFill_Style);
            // The MotionMark code creates a path for fills via lineTo(point), arc(), lineTo(point).
            // For now we'll just use drawArc for both but might need to revisit.
            canvas->drawArc(arcRect, startAngleDeg, sweepAngle, true, paint);
        }
    }

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

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