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        if (prev != DRAWING_OP_TO) {            emitMoveTo(x0 + mx, y0 + my);            this.sdx = dx;            this.sdy = dy;            this.smx = mx;            this.smy = my;        } else {            boolean cw = isCW(pdx, pdy, dx, dy);            if (joinStyle == JOIN_MITER) {                drawMiter(pdx, pdy, x0, y0, dx, dy, omx, omy, mx, my, cw);            } else if (joinStyle == JOIN_ROUND) {                drawRoundJoin(x0, y0,                              omx, omy,                              mx, my, cw,                              ROUND_JOIN_THRESHOLD);            }            emitLineTo(x0, y0, !cw);        }        prev = DRAWING_OP_TO;    }     private static boolean within(final float x1, final float y1,                                  final float x2, final float y2,                                  final float ERR)    {        assert ERR > 0 : "";        // compare taxicab distance. ERR will always be small, so using        // true distance won't give much benefit        return (Helpers.within(x1, x2, ERR) &&  // we want to avoid calling Math.abs                Helpers.within(y1, y2, ERR)); // this is just as good.    }     private void getLineOffsets(float x1, float y1,                                float x2, float y2,                                float[] left, float[] right) {        computeOffset(x2 - x1, y2 - y1, lineWidth2, offset[0]);        left[0] = x1 + offset[0][0];        left[1] = y1 + offset[0][1];        left[2] = x2 + offset[0][0];        left[3] = y2 + offset[0][1];        right[0] = x1 - offset[0][0];        right[1] = y1 - offset[0][1];        right[2] = x2 - offset[0][0];        right[3] = y2 - offset[0][1];    }     private int computeOffsetCubic(float[] pts, final int off,                                   float[] leftOff, float[] rightOff)    {        // if p1=p2 or p3=p4 it means that the derivative at the endpoint        // vanishes, which creates problems with computeOffset. Usually        // this happens when this stroker object is trying to winden        // a curve with a cusp. What happens is that curveTo splits        // the input curve at the cusp, and passes it to this function.        // because of inaccuracies in the splitting, we consider points        // equal if they're very close to each other.        final float x1 = pts[off + 0], y1 = pts[off + 1];        final float x2 = pts[off + 2], y2 = pts[off + 3];        final float x3 = pts[off + 4], y3 = pts[off + 5];        final float x4 = pts[off + 6], y4 = pts[off + 7];         float dx4 = x4 - x3;        float dy4 = y4 - y3;        float dx1 = x2 - x1;        float dy1 = y2 - y1;         // if p1 == p2 && p3 == p4: draw line from p1->p4, unless p1 == p4,        // in which case ignore if p1 == p2        final boolean p1eqp2 = within(x1,y1,x2,y2, 6 * ulp(y2));        final boolean p3eqp4 = within(x3,y3,x4,y4, 6 * ulp(y4));        if (p1eqp2 && p3eqp4) {            getLineOffsets(x1, y1, x4, y4, leftOff, rightOff);            return 4;        } else if (p1eqp2) {            dx1 = x3 - x1;            dy1 = y3 - y1;        } else if (p3eqp4) {            dx4 = x4 - x2;            dy4 = y4 - y2;        }         // if p2-p1 and p4-p3 are parallel, that must mean this curve is a line        float dotsq = (dx1 * dx4 + dy1 * dy4);        dotsq = dotsq * dotsq;        float l1sq = dx1 * dx1 + dy1 * dy1, l4sq = dx4 * dx4 + dy4 * dy4;        if (Helpers.within(dotsq, l1sq * l4sq, 4 * ulp(dotsq))) {            getLineOffsets(x1, y1, x4, y4, leftOff, rightOff);            return 4;        } //      What we're trying to do in this function is to approximate an ideal//      offset curve (call it I) of the input curve B using a bezier curve Bp.//      The constraints I use to get the equations are:////      1. The computed curve Bp should go through I(0) and I(1). These are//      x1p, y1p, x4p, y4p, which are p1p and p4p. We still need to find//      4 variables: the x and y components of p2p and p3p (i.e. x2p, y2p, x3p, y3p).////      2. Bp should have slope equal in absolute value to I at the endpoints. So,//      (by the way, the operator || in the comments below means "aligned with".//      It is defined on vectors, so when we say I'(0) || Bp'(0) we mean that//      vectors I'(0) and Bp'(0) are aligned, which is the same as saying//      that the tangent lines of I and Bp at 0 are parallel. Mathematically//      this means (I'(t) || Bp'(t)) <==> (I'(t) = c * Bp'(t)) where c is some//      nonzero constant.)//      I'(0) || Bp'(0) and I'(1) || Bp'(1). Obviously, I'(0) || B'(0) and//      I'(1) || B'(1); therefore, Bp'(0) || B'(0) and Bp'(1) || B'(1).//      We know that Bp'(0) || (p2p-p1p) and Bp'(1) || (p4p-p3p) and the same//      is true for any bezier curve; therefore, we get the equations//          (1) p2p = c1 * (p2-p1) + p1p//          (2) p3p = c2 * (p4-p3) + p4p//      We know p1p, p4p, p2, p1, p3, and p4; therefore, this reduces the number//      of unknowns from 4 to 2 (i.e. just c1 and c2).//      To eliminate these 2 unknowns we use the following constraint:////      3. Bp(0.5) == I(0.5). Bp(0.5)=(x,y) and I(0.5)=(xi,yi), and I should note//      that I(0.5) is *the only* reason for computing dxm,dym. This gives us//          (3) Bp(0.5) = (p1p + 3 * (p2p + p3p) + p4p)/8, which is equivalent to//          (4) p2p + p3p = (Bp(0.5)*8 - p1p - p4p) / 3//      We can substitute (1) and (2) from above into (4) and we get://          (5) c1*(p2-p1) + c2*(p4-p3) = (Bp(0.5)*8 - p1p - p4p)/3 - p1p - p4p//      which is equivalent to//          (6) c1*(p2-p1) + c2*(p4-p3) = (4/3) * (Bp(0.5) * 2 - p1p - p4p)////      The right side of this is a 2D vector, and we know I(0.5), which gives us//      Bp(0.5), which gives us the value of the right side.//      The left side is just a matrix vector multiplication in disguise. It is////      [x2-x1, x4-x3][c1]//      [y2-y1, y4-y3][c2]//      which, is equal to//      [dx1, dx4][c1]//      [dy1, dy4][c2]//      At this point we are left with a simple linear system and we solve it by//      getting the inverse of the matrix above. Then we use [c1,c2] to compute//      p2p and p3p.         float x = 0.125f * (x1 + 3 * (x2 + x3) + x4);        float y = 0.125f * (y1 + 3 * (y2 + y3) + y4);        // (dxm,dym) is some tangent of B at t=0.5. This means it's equal to        // c*B'(0.5) for some constant c.        float dxm = x3 + x4 - x1 - x2, dym = y3 + y4 - y1 - y2;         // this computes the offsets at t=0, 0.5, 1, using the property that        // for any bezier curve the vectors p2-p1 and p4-p3 are parallel to        // the (dx/dt, dy/dt) vectors at the endpoints.        computeOffset(dx1, dy1, lineWidth2, offset[0]);        computeOffset(dxm, dym, lineWidth2, offset[1]);        computeOffset(dx4, dy4, lineWidth2, offset[2]);        float x1p = x1 + offset[0][0]; // start        float y1p = y1 + offset[0][1]; // point        float xi  = x + offset[1][0]; // interpolation        float yi  = y + offset[1][1]; // point        float x4p = x4 + offset[2][0]; // end        float y4p = y4 + offset[2][1]; // point         float invdet43 = 4f / (3f * (dx1 * dy4 - dy1 * dx4));         float two_pi_m_p1_m_p4x = 2*xi - x1p - x4p;        float two_pi_m_p1_m_p4y = 2*yi - y1p - y4p;        float c1 = invdet43 * (dy4 * two_pi_m_p1_m_p4x - dx4 * two_pi_m_p1_m_p4y);        float c2 = invdet43 * (dx1 * two_pi_m_p1_m_p4y - dy1 * two_pi_m_p1_m_p4x);         float x2p, y2p, x3p, y3p;        x2p = x1p + c1*dx1;        y2p = y1p + c1*dy1;        x3p = x4p + c2*dx4;        y3p = y4p + c2*dy4;         leftOff[0] = x1p; leftOff[1] = y1p;        leftOff[2] = x2p; leftOff[3] = y2p;        leftOff[4] = x3p; leftOff[5] = y3p;        leftOff[6] = x4p; leftOff[7] = y4p;         x1p = x1 - offset[0][0]; y1p = y1 - offset[0][1];        xi = xi - 2 * offset[1][0]; yi = yi - 2 * offset[1][1];        x4p = x4 - offset[2][0]; y4p = y4 - offset[2][1];         two_pi_m_p1_m_p4x = 2*xi - x1p - x4p;        two_pi_m_p1_m_p4y = 2*yi - y1p - y4p;        c1 = invdet43 * (dy4 * two_pi_m_p1_m_p4x - dx4 * two_pi_m_p1_m_p4y);        c2 = invdet43 * (dx1 * two_pi_m_p1_m_p4y - dy1 * two_pi_m_p1_m_p4x);         x2p = x1p + c1*dx1;        y2p = y1p + c1*dy1;        x3p = x4p + c2*dx4;        y3p = y4p + c2*dy4;         rightOff[0] = x1p; rightOff[1] = y1p;        rightOff[2] = x2p; rightOff[3] = y2p;        rightOff[4] = x3p; rightOff[5] = y3p;        rightOff[6] = x4p; rightOff[7] = y4p;        return 8;    }     // return the kind of curve in the right and left arrays.    private int computeOffsetQuad(float[] pts, final int off,                                  float[] leftOff, float[] rightOff)    {        final float x1 = pts[off + 0], y1 = pts[off + 1];        final float x2 = pts[off + 2], y2 = pts[off + 3];        final float x3 = pts[off + 4], y3 = pts[off + 5];         final float dx3 = x3 - x2;        final float dy3 = y3 - y2;        final float dx1 = x2 - x1;        final float dy1 = y2 - y1;         // this computes the offsets at t = 0, 1        computeOffset(dx1, dy1, lineWidth2, offset[0]);        computeOffset(dx3, dy3, lineWidth2, offset[1]);         leftOff[0]  = x1 + offset[0][0];  leftOff[1] = y1 + offset[0][1];        leftOff[4]  = x3 + offset[1][0];  leftOff[5] = y3 + offset[1][1];        rightOff[0] = x1 - offset[0][0]; rightOff[1] = y1 - offset[0][1];        rightOff[4] = x3 - offset[1][0]; rightOff[5] = y3 - offset[1][1];         float x1p = leftOff[0]; // start        float y1p = leftOff[1]; // point        float x3p = leftOff[4]; // end        float y3p = leftOff[5]; // point         // Corner cases:        // 1. If the two control vectors are parallel, we'll end up with NaN's        //    in leftOff (and rightOff in the body of the if below), so we'll        //    do getLineOffsets, which is right.        // 2. If the first or second two points are equal, then (dx1,dy1)==(0,0)        //    or (dx3,dy3)==(0,0), so (x1p, y1p)==(x1p+dx1, y1p+dy1)        //    or (x3p, y3p)==(x3p-dx3, y3p-dy3), which means that        //    computeIntersection will put NaN's in leftOff and right off, and        //    we will do getLineOffsets, which is right.        computeIntersection(x1p, y1p, x1p+dx1, y1p+dy1, x3p, y3p, x3p-dx3, y3p-dy3, leftOff, 2);        float cx = leftOff[2];        float cy = leftOff[3];         if (!(isFinite(cx) && isFinite(cy))) {            // maybe the right path is not degenerate.            x1p = rightOff[0];            y1p = rightOff[1];            x3p = rightOff[4];            y3p = rightOff[5];            computeIntersection(x1p, y1p, x1p+dx1, y1p+dy1, x3p, y3p, x3p-dx3, y3p-dy3, rightOff, 2);            cx = rightOff[2];            cy = rightOff[3];            if (!(isFinite(cx) && isFinite(cy))) {                // both are degenerate. This curve is a line.                getLineOffsets(x1, y1, x3, y3, leftOff, rightOff);                return 4;            }            // {left,right}Off[0,1,4,5] are already set to the correct values.            leftOff[2] = 2*x2 - cx;            leftOff[3] = 2*y2 - cy;            return 6;        }         // rightOff[2,3] = (x2,y2) - ((left_x2, left_y2) - (x2, y2))        // == 2*(x2, y2) - (left_x2, left_y2)        rightOff[2] = 2*x2 - cx;        rightOff[3] = 2*y2 - cy;        return 6;    }     private static boolean isFinite(float x) {        return (Float.NEGATIVE_INFINITY < x && x < Float.POSITIVE_INFINITY);    }     // This is where the curve to be processed is put. We give it    // enough room to store 2 curves: one for the current subdivision, the    // other for the rest of the curve.    private float[] middle = new float[2*8];    private float[] lp = new float[8];    private float[] rp = new float[8];    private static final int MAX_N_CURVES = 11;    private float[] subdivTs = new float[MAX_N_CURVES - 1];     // If this class is compiled with ecj, then Hotspot crashes when OSR    // compiling this function. See bugs 7004570 and 6675699    // TODO: until those are fixed, we should work around that by    // manually inlining this into curveTo and quadTo./******************************* WORKAROUND **********************************    private void somethingTo(final int type) {        // need these so we can update the state at the end of this method        final float xf = middle[type-2], yf = middle[type-1];        float dxs = middle[2] - middle[0];        float dys = middle[3] - middle[1];        float dxf = middle[type - 2] - middle[type - 4];        float dyf = middle[type - 1] - middle[type - 3];        switch(type) {        case 6:            if ((dxs == 0f && dys == 0f) ||                (dxf == 0f && dyf == 0f)) {               dxs = dxf = middle[4] - middle[0];               dys = dyf = middle[5] - middle[1];            }            break;        case 8:            boolean p1eqp2 = (dxs == 0f && dys == 0f);            boolean p3eqp4 = (dxf == 0f && dyf == 0f);            if (p1eqp2) {                dxs = middle[4] - middle[0];                dys = middle[5] - middle[1];                if (dxs == 0f && dys == 0f) {                    dxs = middle[6] - middle[0];                    dys = middle[7] - middle[1];                }            }            if (p3eqp4) {                dxf = middle[6] - middle[2];                dyf = middle[7] - middle[3];                if (dxf == 0f && dyf == 0f) {                    dxf = middle[6] - middle[0];                    dyf = middle[7] - middle[1];                }            }        }        if (dxs == 0f && dys == 0f) {            // this happens iff the "curve" is just a point            lineTo(middle[0], middle[1]);            return;        }        // if these vectors are too small, normalize them, to avoid future        // precision problems.        if (Math.abs(dxs) < 0.1f && Math.abs(dys) < 0.1f) {            float len = (float) sqrt(dxs*dxs + dys*dys);            dxs /= len;            dys /= len;        }        if (Math.abs(dxf) < 0.1f && Math.abs(dyf) < 0.1f) {            float len = (float) sqrt(dxf*dxf + dyf*dyf);            dxf /= len;            dyf /= len;        }         computeOffset(dxs, dys, lineWidth2, offset[0]);        final float mx = offset[0][0];        final float my = offset[0][1];        drawJoin(cdx, cdy, cx0, cy0, dxs, dys, cmx, cmy, mx, my);         int nSplits = findSubdivPoints(middle, subdivTs, type, lineWidth2);         int kind = 0;        Iterator<Integer> it = Curve.breakPtsAtTs(middle, type, subdivTs, nSplits);        while(it.hasNext()) {            int curCurveOff = it.next();             switch (type) {            case 8:                kind = computeOffsetCubic(middle, curCurveOff, lp, rp);                break;            case 6:                kind = computeOffsetQuad(middle, curCurveOff, lp, rp);                break;            }            emitLineTo(lp[0], lp[1]);            switch(kind) {            case 8:                emitCurveTo(lp[0], lp[1], lp[2], lp[3], lp[4], lp[5], lp[6], lp[7], false);                emitCurveTo(rp[0], rp[1], rp[2], rp[3], rp[4], rp[5], rp[6], rp[7], true);                break;            case 6:                emitQuadTo(lp[0], lp[1], lp[2], lp[3], lp[4], lp[5], false);                emitQuadTo(rp[0], rp[1], rp[2], rp[3], rp[4], rp[5], true);                break;            case 4:                emitLineTo(lp[2], lp[3]);                emitLineTo(rp[0], rp[1], true);                break;            }            emitLineTo(rp[kind - 2], rp[kind - 1], true);        }         this.cmx = (lp[kind - 2] - rp[kind - 2]) / 2;        this.cmy = (lp[kind - 1] - rp[kind - 1]) / 2;        this.cdx = dxf;        this.cdy = dyf;        this.cx0 = xf;        this.cy0 = yf;        this.prev = DRAWING_OP_TO;    }****************************** END WORKAROUND *******************************/     // finds values of t where the curve in pts should be subdivided in order    // to get good offset curves a distance of w away from the middle curve.    // Stores the points in ts, and returns how many of them there were.    private static Curve c = new Curve();    private static int findSubdivPoints(float[] pts, float[] ts, final int type, final float w)    {        final float x12 = pts[2] - pts[0];        final float y12 = pts[3] - pts[1];        // if the curve is already parallel to either axis we gain nothing        // from rotating it.        if (y12 != 0f && x12 != 0f) {            // we rotate it so that the first vector in the control polygon is            // parallel to the x-axis. This will ensure that rotated quarter            // circles won't be subdivided.            final float hypot = (float) sqrt(x12 * x12 + y12 * y12);            final float cos = x12 / hypot;            final float sin = y12 / hypot;            final float x1 = cos * pts[0] + sin * pts[1];            final float y1 = cos * pts[1] - sin * pts[0];            final float x2 = cos * pts[2] + sin * pts[3];            final float y2 = cos * pts[3] - sin * pts[2];            final float x3 = cos * pts[4] + sin * pts[5];            final float y3 = cos * pts[5] - sin * pts[4];            switch(type) {            case 8:                final float x4 = cos * pts[6] + sin * pts[7];                final float y4 = cos * pts[7] - sin * pts[6];                c.set(x1, y1, x2, y2, x3, y3, x4, y4);                break;            case 6:                c.set(x1, y1, x2, y2, x3, y3);                break;            }        } else {            c.set(pts, type);        }         int ret = 0;        // we subdivide at values of t such that the remaining rotated        // curves are monotonic in x and y.        ret += c.dxRoots(ts, ret);        ret += c.dyRoots(ts, ret);        // subdivide at inflection points.        if (type == 8) {            // quadratic curves can't have inflection points            ret += c.infPoints(ts, ret);        }         // now we must subdivide at points where one of the offset curves will have        // a cusp. This happens at ts where the radius of curvature is equal to w.        ret += c.rootsOfROCMinusW(ts, ret, w, 0.0001f);         ret = Helpers.filterOutNotInAB(ts, 0, ret, 0.0001f, 0.9999f);        Helpers.isort(ts, 0, ret);        return ret;    }     @Override public void curveTo(float x1, float y1,                                  float x2, float y2,                                  float x3, float y3)    {        middle[0] = cx0; middle[1] = cy0;        middle[2] = x1;  middle[3] = y1;        middle[4] = x2;  middle[5] = y2;        middle[6] = x3;  middle[7] = y3;         // inlined version of somethingTo(8);        // See the TODO on somethingTo         // need these so we can update the state at the end of this method        final float xf = middle[6], yf = middle[7];        float dxs = middle[2] - middle[0];        float dys = middle[3] - middle[1];        float dxf = middle[6] - middle[4];        float dyf = middle[7] - middle[5];         boolean p1eqp2 = (dxs == 0f && dys == 0f);        boolean p3eqp4 = (dxf == 0f && dyf == 0f);        if (p1eqp2) {            dxs = middle[4] - middle[0];            dys = middle[5] - middle[1];            if (dxs == 0f && dys == 0f) {                dxs = middle[6] - middle[0];                dys = middle[7] - middle[1];            }        }        if (p3eqp4) {            dxf = middle[6] - middle[2];            dyf = middle[7] - middle[3];            if (dxf == 0f && dyf == 0f) {                dxf = middle[6] - middle[0];                dyf = middle[7] - middle[1];            }        }        if (dxs == 0f && dys == 0f) {            // this happens iff the "curve" is just a point            lineTo(middle[0], middle[1]);            return;        }         // if these vectors are too small, normalize them, to avoid future        // precision problems.        if (Math.abs(dxs) < 0.1f && Math.abs(dys) < 0.1f) {            float len = (float) sqrt(dxs*dxs + dys*dys);            dxs /= len;            dys /= len;        }        if (Math.abs(dxf) < 0.1f && Math.abs(dyf) < 0.1f) {            float len = (float) sqrt(dxf*dxf + dyf*dyf);            dxf /= len;            dyf /= len;        }         computeOffset(dxs, dys, lineWidth2, offset[0]);        final float mx = offset[0][0];        final float my = offset[0][1];        drawJoin(cdx, cdy, cx0, cy0, dxs, dys, cmx, cmy, mx, my);         int nSplits = findSubdivPoints(middle, subdivTs, 8, lineWidth2);

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