C++ SkPath::addArc方法代码示例

	virtual void getWarpParams(WarpFrameT& warpFrame, SkMatrix& warpMatrix) const
	{
		SkPath bSkeleton, tSkeleton;

		SkRect r;
		r.set(SkIntToScalar(0), SkIntToScalar(0),
				SkIntToScalar(600), SkIntToScalar(340));

		//bottom
		{
			SkRect rb(r);
			rb.inset(SkIntToScalar(-240), SkIntToScalar(-140));

			SkPath tmp;
			tmp.addArc(rb, SkIntToScalar(0), SkIntToScalar(180));
			bSkeleton.reverseAddPath(tmp);

			warpFrame.push_back(bSkeleton);
		}

		//top
		{
			

			SkPath tmp;
			tmp.addArc(r, SkIntToScalar(0), SkIntToScalar(180));
			tSkeleton.reverseAddPath(tmp);

			warpFrame.push_back(tSkeleton);
		}
	}

void GraphicsContext::strokeArc(const IntRect& r, int startAngle, int angleSpan)
{
    if (paintingDisabled())
        return;

    SkPaint paint;
    SkRect oval = r;
    if (strokeStyle() == NoStroke) {
        // Stroke using the fill color.
        // TODO(brettw) is this really correct? It seems unreasonable.
        platformContext()->setupPaintForFilling(&paint);
        paint.setStyle(SkPaint::kStroke_Style);
        paint.setStrokeWidth(WebCoreFloatToSkScalar(strokeThickness()));
    } else
        platformContext()->setupPaintForStroking(&paint, 0, 0);

    // We do this before converting to scalar, so we don't overflow SkFixed.
    startAngle = fastMod(startAngle, 360);
    angleSpan = fastMod(angleSpan, 360);

    SkPath path;
    path.addArc(oval, SkIntToScalar(-startAngle), SkIntToScalar(-angleSpan));
    if (!isPathSkiaSafe(getCTM(), path))
        return;
    platformContext()->canvas()->drawPath(path, paint);
}

    void onDraw(SkCanvas* canvas) override {
        canvas->translate(20, 20);

        SkRect r = SkRect::MakeWH(1000, 1000);

        SkPaint paint;
        paint.setAntiAlias(true);
        paint.setStyle(SkPaint::kStroke_Style);
        paint.setStrokeWidth(15);

        const SkScalar inset = paint.getStrokeWidth() + 4;
        const SkScalar sweepAngle = 345;
        SkRandom rand;

        SkScalar sign = 1;
        while (r.width() > paint.getStrokeWidth() * 3) {
            paint.setColor(sk_tool_utils::color_to_565(rand.nextU() | (0xFF << 24)));
            SkScalar startAngle = rand.nextUScalar1() * 360;

            SkScalar speed = SkScalarSqrt(16 / r.width()) * 0.5f;
            startAngle += fRotate * 360 * speed * sign;

            SkPath path;
            path.addArc(r, startAngle, sweepAngle);
            canvas->drawPath(path, paint);

            r.inset(inset, inset);
            sign = -sign;
        }
    }

static void textStrokePath(SkCanvas* canvas) {
    SkPaint paint;
    SkPath  path;
    SkRect  rect;

    canvas->save();
    canvas->scale(SkIntToScalar(250),SkIntToScalar(250));

    rect.set(0.0f,  0.21f,
             0.78f, 0.99f);

    path.addArc(rect, SkIntToScalar(280), SkIntToScalar(350));

    paint.setAntiAlias(true);
    paint.setStyle(SkPaint::kStroke_Style);
    paint.setColor(0xFFFF0000);
    paint.setTextSize(0.085f);
    paint.setStrokeWidth(.005f);

    canvas->drawPath(path, paint);

    paint.setLooper(SkBlurDrawLooper::Create(SK_ColorBLACK,
                                             SkBlurMask::ConvertRadiusToSigma(0.002f),
                                             0.0f,
                                             0.0f))->unref();

    const char* text = "DRAWING STROKED TEXT WITH A BLUR ON A PATH";
    size_t      len = strlen(text);

    canvas->drawTextOnPathHV(text, len, path, 0,
                             -0.025f, paint);
    canvas->restore();
}

void ACanvasSkia::DrawEllipse(ARect r)
{
	_clip();
	_SetPaint_Draw();
	SkPath path;
	path.addArc(ToSkRect(r),0,360);
	m_pCanvas->drawPath(path,m_Paint);
	Reset();
}

//.........这里部分代码省略.........
            unevenTighterQuad->quadTo(SkIntToScalar(100), SkIntToScalar(100), p.fX, p.fY);
        }

        {
            SkPath* reallyTightQuad = &fPaths.push_back();
            reallyTightQuad->moveTo(0, -1 * SK_Scalar1);
            reallyTightQuad->quadTo(SkIntToScalar(100), SkIntToScalar(100), -1 * SK_Scalar1, 0);
        }

        {
            SkPath* closedQuad = &fPaths.push_back();
            closedQuad->moveTo(0, -0);
            closedQuad->quadTo(SkIntToScalar(100), SkIntToScalar(100), 0, 0);
        }

        {
            SkPath* unevenClosedQuad = &fPaths.push_back();
            unevenClosedQuad->moveTo(0, -0);
            unevenClosedQuad->quadTo(SkIntToScalar(100), SkIntToScalar(100),
                                     SkIntToScalar(75), SkIntToScalar(75));
        }

        // Two problem cases for gpu hairline renderer found by shapeops testing. These used
        // to assert that the computed bounding box didn't contain all the vertices.
        {
            SkPath* problem1 = &fPaths.push_back();
            problem1->moveTo(SkIntToScalar(4), SkIntToScalar(6));
            problem1->cubicTo(SkIntToScalar(5), SkIntToScalar(6),
                              SkIntToScalar(5), SkIntToScalar(4),
                              SkIntToScalar(4), SkIntToScalar(0));
            problem1->close();
        }

        {
            SkPath* problem2 = &fPaths.push_back();
            problem2->moveTo(SkIntToScalar(5), SkIntToScalar(1));
            problem2->lineTo(4.32787323f, 1.67212653f);
            problem2->cubicTo(2.75223875f, 3.24776125f,
                              3.00581908f, 4.51236057f,
                              3.7580452f, 4.37367964f);
            problem2->cubicTo(4.66472578f, 3.888381f,
                              5.f, 2.875f,
                              5.f, 1.f);
            problem2->close();
        }

        // Three paths that show the same bug (missing end caps)
        {
            // A caret (crbug.com/131770)
            SkPath* bug0 = &fPaths.push_back();
            bug0->moveTo(6.5f,5.5f);
            bug0->lineTo(3.5f,0.5f);
            bug0->moveTo(0.5f,5.5f);
            bug0->lineTo(3.5f,0.5f);
        }

        {
            // An X (crbug.com/137317)
            SkPath* bug1 = &fPaths.push_back();

            bug1->moveTo(1, 1);
            bug1->lineTo(6, 6);
            bug1->moveTo(1, 6);
            bug1->lineTo(6, 1);
        }

        {
            // A right angle (crbug.com/137465 and crbug.com/256776)
            SkPath* bug2 = &fPaths.push_back();

            bug2->moveTo(5.5f, 5.5f);
            bug2->lineTo(5.5f, 0.5f);
            bug2->lineTo(0.5f, 0.5f);
        }

        {
            // Arc example to test imperfect truncation bug (crbug.com/295626)
            static const SkScalar kRad = SkIntToScalar(2000);
            static const SkScalar kStartAngle = 262.59717f;
            static const SkScalar kSweepAngle = SkScalarHalf(17.188717f);

            SkPath* bug = &fPaths.push_back();

            // Add a circular arc
            SkRect circle = SkRect::MakeLTRB(-kRad, -kRad, kRad, kRad);
            bug->addArc(circle, kStartAngle, kSweepAngle);

            // Now add the chord that should cap the circular arc
            SkScalar cosV, sinV = SkScalarSinCos(SkDegreesToRadians(kStartAngle), &cosV);

            SkPoint p0 = SkPoint::Make(kRad * cosV, kRad * sinV);

            sinV = SkScalarSinCos(SkDegreesToRadians(kStartAngle + kSweepAngle), &cosV);

            SkPoint p1 = SkPoint::Make(kRad * cosV, kRad * sinV);

            bug->moveTo(p0);
            bug->lineTo(p1);
        }
    }

SkPath makePath() {
    SkPath path;
    for (uint32_t cIndex = 0; cIndex < fPathContourCount; ++cIndex) {
        uint32_t segments = makeSegmentCount();
        for (uint32_t sIndex = 0; sIndex < segments; ++sIndex) {
            RandomAddPath addPathType = makeAddPathType();
            ++fAddCount;
            if (fPrintName) {
                SkDebugf("%.*s%s\n", fPathDepth * 3, fTab,
                        gRandomAddPathNames[addPathType]);
            }
            switch (addPathType) {
                case kAddArc: {
                    SkRect oval = makeRect();
                    SkScalar startAngle = makeAngle();
                    SkScalar sweepAngle = makeAngle();
                    path.addArc(oval, startAngle, sweepAngle);
                    validate(path);
                    } break;
                case kAddRoundRect1: {
                    SkRect rect = makeRect();
                    SkScalar rx = makeScalar(), ry = makeScalar();
                    SkPath::Direction dir = makeDirection();
                    path.addRoundRect(rect, rx, ry, dir);
                    validate(path);
                    } break;
                case kAddRoundRect2: {
                    SkRect rect = makeRect();
                    SkScalar radii[8];
                    makeScalarArray(SK_ARRAY_COUNT(radii), radii);
                    SkPath::Direction dir = makeDirection();
                    path.addRoundRect(rect, radii, dir);
                    validate(path);
                    } break;
                case kAddRRect: {
                    SkRRect rrect = makeRRect();
                    SkPath::Direction dir = makeDirection();
                    path.addRRect(rrect, dir);
                    validate(path);
                    } break;
                case kAddPoly: {
                    SkTDArray<SkPoint> points;
                    makePointArray(&points);
                    bool close = makeBool();
                    path.addPoly(&points[0], points.count(), close);
                    validate(path);
                    } break;
                case kAddPath1:
                    if (fPathDepth < fPathDepthLimit) {
                        ++fPathDepth;
                        SkPath src = makePath();
                        validate(src);
                        SkScalar dx = makeScalar();
                        SkScalar dy = makeScalar();
                        SkPath::AddPathMode mode = makeAddPathMode();
                        path.addPath(src, dx, dy, mode);
                        --fPathDepth;
                        validate(path);
                    }
                    break;
                case kAddPath2:
                    if (fPathDepth < fPathDepthLimit) {
                        ++fPathDepth;
                        SkPath src = makePath();
                        validate(src);
                        SkPath::AddPathMode mode = makeAddPathMode();
                        path.addPath(src, mode);
                        --fPathDepth;
                        validate(path);
                    }
                    break;
                case kAddPath3:
                    if (fPathDepth < fPathDepthLimit) {
                        ++fPathDepth;
                        SkPath src = makePath();
                        validate(src);
                        SkMatrix matrix = makeMatrix();
                        SkPath::AddPathMode mode = makeAddPathMode();
                        path.addPath(src, matrix, mode);
                        --fPathDepth;
                        validate(path);
                    }
                    break;
                case kReverseAddPath:
                    if (fPathDepth < fPathDepthLimit) {
                        ++fPathDepth;
                        SkPath src = makePath();
                        validate(src);
                        path.reverseAddPath(src);
                        --fPathDepth;
                        validate(path);
                    }
                    break;
                case kMoveToPath: {
                    SkScalar x = makeScalar();
                    SkScalar y = makeScalar();
                    path.moveTo(x, y);
                    validate(path);
                    } break;
                case kRMoveToPath: {
//.........这里部分代码省略.........