| /* |
| * Copyright (c) 2007, 2017, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| package sun.java2d.marlin; |
| |
| import java.util.Arrays; |
| import sun.java2d.marlin.DHelpers.PolyStack; |
| import sun.java2d.marlin.DTransformingPathConsumer2D.CurveBasicMonotonizer; |
| import sun.java2d.marlin.DTransformingPathConsumer2D.CurveClipSplitter; |
| |
| // TODO: some of the arithmetic here is too verbose and prone to hard to |
| // debug typos. We should consider making a small Point/Vector class that |
| // has methods like plus(Point), minus(Point), dot(Point), cross(Point)and such |
| final class DStroker implements DPathConsumer2D, MarlinConst { |
| |
| private static final int MOVE_TO = 0; |
| private static final int DRAWING_OP_TO = 1; // ie. curve, line, or quad |
| private static final int CLOSE = 2; |
| |
| // round join threshold = 1 subpixel |
| private static final double ERR_JOIN = (1.0f / MIN_SUBPIXELS); |
| private static final double ROUND_JOIN_THRESHOLD = ERR_JOIN * ERR_JOIN; |
| |
| // kappa = (4/3) * (SQRT(2) - 1) |
| private static final double C = (4.0d * (Math.sqrt(2.0d) - 1.0d) / 3.0d); |
| |
| // SQRT(2) |
| private static final double SQRT_2 = Math.sqrt(2.0d); |
| |
| private DPathConsumer2D out; |
| |
| private int capStyle; |
| private int joinStyle; |
| |
| private double lineWidth2; |
| private double invHalfLineWidth2Sq; |
| |
| private final double[] offset0 = new double[2]; |
| private final double[] offset1 = new double[2]; |
| private final double[] offset2 = new double[2]; |
| private final double[] miter = new double[2]; |
| private double miterLimitSq; |
| |
| private int prev; |
| |
| // The starting point of the path, and the slope there. |
| private double sx0, sy0, sdx, sdy; |
| // the current point and the slope there. |
| private double cx0, cy0, cdx, cdy; // c stands for current |
| // vectors that when added to (sx0,sy0) and (cx0,cy0) respectively yield the |
| // first and last points on the left parallel path. Since this path is |
| // parallel, it's slope at any point is parallel to the slope of the |
| // original path (thought they may have different directions), so these |
| // could be computed from sdx,sdy and cdx,cdy (and vice versa), but that |
| // would be error prone and hard to read, so we keep these anyway. |
| private double smx, smy, cmx, cmy; |
| |
| private final PolyStack reverse; |
| |
| private final double[] lp = new double[8]; |
| private final double[] rp = new double[8]; |
| |
| // per-thread renderer context |
| final DRendererContext rdrCtx; |
| |
| // dirty curve |
| final DCurve curve; |
| |
| // Bounds of the drawing region, at pixel precision. |
| private double[] clipRect; |
| |
| // the outcode of the current point |
| private int cOutCode = 0; |
| |
| // the outcode of the starting point |
| private int sOutCode = 0; |
| |
| // flag indicating if the path is opened (clipped) |
| private boolean opened = false; |
| // flag indicating if the starting point's cap is done |
| private boolean capStart = false; |
| // flag indicating to monotonize curves |
| private boolean monotonize; |
| |
| private boolean subdivide = false; |
| private final CurveClipSplitter curveSplitter; |
| |
| /** |
| * Constructs a <code>DStroker</code>. |
| * @param rdrCtx per-thread renderer context |
| */ |
| DStroker(final DRendererContext rdrCtx) { |
| this.rdrCtx = rdrCtx; |
| |
| this.reverse = (rdrCtx.stats != null) ? |
| new PolyStack(rdrCtx, |
| rdrCtx.stats.stat_str_polystack_types, |
| rdrCtx.stats.stat_str_polystack_curves, |
| rdrCtx.stats.hist_str_polystack_curves, |
| rdrCtx.stats.stat_array_str_polystack_curves, |
| rdrCtx.stats.stat_array_str_polystack_types) |
| : new PolyStack(rdrCtx); |
| |
| this.curve = rdrCtx.curve; |
| this.curveSplitter = rdrCtx.curveClipSplitter; |
| } |
| |
| /** |
| * Inits the <code>DStroker</code>. |
| * |
| * @param pc2d an output <code>DPathConsumer2D</code>. |
| * @param lineWidth the desired line width in pixels |
| * @param capStyle the desired end cap style, one of |
| * <code>CAP_BUTT</code>, <code>CAP_ROUND</code> or |
| * <code>CAP_SQUARE</code>. |
| * @param joinStyle the desired line join style, one of |
| * <code>JOIN_MITER</code>, <code>JOIN_ROUND</code> or |
| * <code>JOIN_BEVEL</code>. |
| * @param miterLimit the desired miter limit |
| * @param scale scaling factor applied to clip boundaries |
| * @param subdivideCurves true to indicate to subdivide curves, false if dasher does |
| * @return this instance |
| */ |
| DStroker init(final DPathConsumer2D pc2d, |
| final double lineWidth, |
| final int capStyle, |
| final int joinStyle, |
| final double miterLimit, |
| final double scale, |
| final boolean subdivideCurves) |
| { |
| this.out = pc2d; |
| |
| this.lineWidth2 = lineWidth / 2.0d; |
| this.invHalfLineWidth2Sq = 1.0d / (2.0d * lineWidth2 * lineWidth2); |
| this.monotonize = subdivideCurves; |
| |
| this.capStyle = capStyle; |
| this.joinStyle = joinStyle; |
| |
| final double limit = miterLimit * lineWidth2; |
| this.miterLimitSq = limit * limit; |
| |
| this.prev = CLOSE; |
| |
| rdrCtx.stroking = 1; |
| |
| if (rdrCtx.doClip) { |
| // Adjust the clipping rectangle with the stroker margin (miter limit, width) |
| double rdrOffX = 0.0d, rdrOffY = 0.0d; |
| double margin = lineWidth2; |
| |
| if (capStyle == CAP_SQUARE) { |
| margin *= SQRT_2; |
| } |
| if ((joinStyle == JOIN_MITER) && (margin < limit)) { |
| margin = limit; |
| } |
| if (scale != 1.0d) { |
| margin *= scale; |
| rdrOffX = scale * DRenderer.RDR_OFFSET_X; |
| rdrOffY = scale * DRenderer.RDR_OFFSET_Y; |
| } |
| // add a small rounding error: |
| margin += 1e-3d; |
| |
| // bounds as half-open intervals: minX <= x < maxX and minY <= y < maxY |
| // adjust clip rectangle (ymin, ymax, xmin, xmax): |
| final double[] _clipRect = rdrCtx.clipRect; |
| _clipRect[0] -= margin - rdrOffY; |
| _clipRect[1] += margin + rdrOffY; |
| _clipRect[2] -= margin - rdrOffX; |
| _clipRect[3] += margin + rdrOffX; |
| this.clipRect = _clipRect; |
| |
| // initialize curve splitter here for stroker & dasher: |
| if (DO_CLIP_SUBDIVIDER) { |
| subdivide = subdivideCurves; |
| // adjust padded clip rectangle: |
| curveSplitter.init(); |
| } else { |
| subdivide = false; |
| } |
| } else { |
| this.clipRect = null; |
| this.cOutCode = 0; |
| this.sOutCode = 0; |
| } |
| return this; // fluent API |
| } |
| |
| void disableClipping() { |
| this.clipRect = null; |
| this.cOutCode = 0; |
| this.sOutCode = 0; |
| } |
| |
| /** |
| * Disposes this stroker: |
| * clean up before reusing this instance |
| */ |
| void dispose() { |
| reverse.dispose(); |
| |
| opened = false; |
| capStart = false; |
| |
| if (DO_CLEAN_DIRTY) { |
| // Force zero-fill dirty arrays: |
| Arrays.fill(offset0, 0.0d); |
| Arrays.fill(offset1, 0.0d); |
| Arrays.fill(offset2, 0.0d); |
| Arrays.fill(miter, 0.0d); |
| Arrays.fill(lp, 0.0d); |
| Arrays.fill(rp, 0.0d); |
| } |
| } |
| |
| private static void computeOffset(final double lx, final double ly, |
| final double w, final double[] m) |
| { |
| double len = lx*lx + ly*ly; |
| if (len == 0.0d) { |
| m[0] = 0.0d; |
| m[1] = 0.0d; |
| } else { |
| len = Math.sqrt(len); |
| m[0] = (ly * w) / len; |
| m[1] = -(lx * w) / len; |
| } |
| } |
| |
| // Returns true if the vectors (dx1, dy1) and (dx2, dy2) are |
| // clockwise (if dx1,dy1 needs to be rotated clockwise to close |
| // the smallest angle between it and dx2,dy2). |
| // This is equivalent to detecting whether a point q is on the right side |
| // of a line passing through points p1, p2 where p2 = p1+(dx1,dy1) and |
| // q = p2+(dx2,dy2), which is the same as saying p1, p2, q are in a |
| // clockwise order. |
| // NOTE: "clockwise" here assumes coordinates with 0,0 at the bottom left. |
| private static boolean isCW(final double dx1, final double dy1, |
| final double dx2, final double dy2) |
| { |
| return dx1 * dy2 <= dy1 * dx2; |
| } |
| |
| private void mayDrawRoundJoin(double cx, double cy, |
| double omx, double omy, |
| double mx, double my, |
| boolean rev) |
| { |
| if ((omx == 0.0d && omy == 0.0d) || (mx == 0.0d && my == 0.0d)) { |
| return; |
| } |
| |
| final double domx = omx - mx; |
| final double domy = omy - my; |
| final double lenSq = domx*domx + domy*domy; |
| |
| if (lenSq < ROUND_JOIN_THRESHOLD) { |
| return; |
| } |
| |
| if (rev) { |
| omx = -omx; |
| omy = -omy; |
| mx = -mx; |
| my = -my; |
| } |
| drawRoundJoin(cx, cy, omx, omy, mx, my, rev); |
| } |
| |
| private void drawRoundJoin(double cx, double cy, |
| double omx, double omy, |
| double mx, double my, |
| boolean rev) |
| { |
| // The sign of the dot product of mx,my and omx,omy is equal to the |
| // the sign of the cosine of ext |
| // (ext is the angle between omx,omy and mx,my). |
| final double cosext = omx * mx + omy * my; |
| // If it is >=0, we know that abs(ext) is <= 90 degrees, so we only |
| // need 1 curve to approximate the circle section that joins omx,omy |
| // and mx,my. |
| final int numCurves = (cosext >= 0.0d) ? 1 : 2; |
| |
| switch (numCurves) { |
| case 1: |
| drawBezApproxForArc(cx, cy, omx, omy, mx, my, rev); |
| break; |
| case 2: |
| // we need to split the arc into 2 arcs spanning the same angle. |
| // The point we want will be one of the 2 intersections of the |
| // perpendicular bisector of the chord (omx,omy)->(mx,my) and the |
| // circle. We could find this by scaling the vector |
| // (omx+mx, omy+my)/2 so that it has length=lineWidth2 (and thus lies |
| // on the circle), but that can have numerical problems when the angle |
| // between omx,omy and mx,my is close to 180 degrees. So we compute a |
| // normal of (omx,omy)-(mx,my). This will be the direction of the |
| // perpendicular bisector. To get one of the intersections, we just scale |
| // this vector that its length is lineWidth2 (this works because the |
| // perpendicular bisector goes through the origin). This scaling doesn't |
| // have numerical problems because we know that lineWidth2 divided by |
| // this normal's length is at least 0.5 and at most sqrt(2)/2 (because |
| // we know the angle of the arc is > 90 degrees). |
| double nx = my - omy, ny = omx - mx; |
| double nlen = Math.sqrt(nx*nx + ny*ny); |
| double scale = lineWidth2/nlen; |
| double mmx = nx * scale, mmy = ny * scale; |
| |
| // if (isCW(omx, omy, mx, my) != isCW(mmx, mmy, mx, my)) then we've |
| // computed the wrong intersection so we get the other one. |
| // The test above is equivalent to if (rev). |
| if (rev) { |
| mmx = -mmx; |
| mmy = -mmy; |
| } |
| drawBezApproxForArc(cx, cy, omx, omy, mmx, mmy, rev); |
| drawBezApproxForArc(cx, cy, mmx, mmy, mx, my, rev); |
| break; |
| default: |
| } |
| } |
| |
| // the input arc defined by omx,omy and mx,my must span <= 90 degrees. |
| private void drawBezApproxForArc(final double cx, final double cy, |
| final double omx, final double omy, |
| final double mx, final double my, |
| boolean rev) |
| { |
| final double cosext2 = (omx * mx + omy * my) * invHalfLineWidth2Sq; |
| |
| // check round off errors producing cos(ext) > 1 and a NaN below |
| // cos(ext) == 1 implies colinear segments and an empty join anyway |
| if (cosext2 >= 0.5d) { |
| // just return to avoid generating a flat curve: |
| return; |
| } |
| |
| // cv is the length of P1-P0 and P2-P3 divided by the radius of the arc |
| // (so, cv assumes the arc has radius 1). P0, P1, P2, P3 are the points that |
| // define the bezier curve we're computing. |
| // It is computed using the constraints that P1-P0 and P3-P2 are parallel |
| // to the arc tangents at the endpoints, and that |P1-P0|=|P3-P2|. |
| double cv = ((4.0d / 3.0d) * Math.sqrt(0.5d - cosext2) / |
| (1.0d + Math.sqrt(cosext2 + 0.5d))); |
| // if clockwise, we need to negate cv. |
| if (rev) { // rev is equivalent to isCW(omx, omy, mx, my) |
| cv = -cv; |
| } |
| final double x1 = cx + omx; |
| final double y1 = cy + omy; |
| final double x2 = x1 - cv * omy; |
| final double y2 = y1 + cv * omx; |
| |
| final double x4 = cx + mx; |
| final double y4 = cy + my; |
| final double x3 = x4 + cv * my; |
| final double y3 = y4 - cv * mx; |
| |
| emitCurveTo(x1, y1, x2, y2, x3, y3, x4, y4, rev); |
| } |
| |
| private void drawRoundCap(double cx, double cy, double mx, double my) { |
| final double Cmx = C * mx; |
| final double Cmy = C * my; |
| emitCurveTo(cx + mx - Cmy, cy + my + Cmx, |
| cx - my + Cmx, cy + mx + Cmy, |
| cx - my, cy + mx); |
| emitCurveTo(cx - my - Cmx, cy + mx - Cmy, |
| cx - mx - Cmy, cy - my + Cmx, |
| cx - mx, cy - my); |
| } |
| |
| // Return the intersection point of the lines (x0, y0) -> (x1, y1) |
| // and (x0p, y0p) -> (x1p, y1p) in m[off] and m[off+1] |
| private static void computeMiter(final double x0, final double y0, |
| final double x1, final double y1, |
| final double x0p, final double y0p, |
| final double x1p, final double y1p, |
| final double[] m) |
| { |
| double x10 = x1 - x0; |
| double y10 = y1 - y0; |
| double x10p = x1p - x0p; |
| double y10p = y1p - y0p; |
| |
| // if this is 0, the lines are parallel. If they go in the |
| // same direction, there is no intersection so m[off] and |
| // m[off+1] will contain infinity, so no miter will be drawn. |
| // If they go in the same direction that means that the start of the |
| // current segment and the end of the previous segment have the same |
| // tangent, in which case this method won't even be involved in |
| // miter drawing because it won't be called by drawMiter (because |
| // (mx == omx && my == omy) will be true, and drawMiter will return |
| // immediately). |
| double den = x10*y10p - x10p*y10; |
| double t = x10p*(y0-y0p) - y10p*(x0-x0p); |
| t /= den; |
| m[0] = x0 + t*x10; |
| m[1] = y0 + t*y10; |
| } |
| |
| // Return the intersection point of the lines (x0, y0) -> (x1, y1) |
| // and (x0p, y0p) -> (x1p, y1p) in m[off] and m[off+1] |
| private static void safeComputeMiter(final double x0, final double y0, |
| final double x1, final double y1, |
| final double x0p, final double y0p, |
| final double x1p, final double y1p, |
| final double[] m) |
| { |
| double x10 = x1 - x0; |
| double y10 = y1 - y0; |
| double x10p = x1p - x0p; |
| double y10p = y1p - y0p; |
| |
| // if this is 0, the lines are parallel. If they go in the |
| // same direction, there is no intersection so m[off] and |
| // m[off+1] will contain infinity, so no miter will be drawn. |
| // If they go in the same direction that means that the start of the |
| // current segment and the end of the previous segment have the same |
| // tangent, in which case this method won't even be involved in |
| // miter drawing because it won't be called by drawMiter (because |
| // (mx == omx && my == omy) will be true, and drawMiter will return |
| // immediately). |
| double den = x10*y10p - x10p*y10; |
| if (den == 0.0d) { |
| m[2] = (x0 + x0p) / 2.0d; |
| m[3] = (y0 + y0p) / 2.0d; |
| } else { |
| double t = x10p*(y0-y0p) - y10p*(x0-x0p); |
| t /= den; |
| m[2] = x0 + t*x10; |
| m[3] = y0 + t*y10; |
| } |
| } |
| |
| private void drawMiter(final double pdx, final double pdy, |
| final double x0, final double y0, |
| final double dx, final double dy, |
| double omx, double omy, |
| double mx, double my, |
| boolean rev) |
| { |
| if ((mx == omx && my == omy) || |
| (pdx == 0.0d && pdy == 0.0d) || |
| (dx == 0.0d && dy == 0.0d)) |
| { |
| return; |
| } |
| |
| if (rev) { |
| omx = -omx; |
| omy = -omy; |
| mx = -mx; |
| my = -my; |
| } |
| |
| computeMiter((x0 - pdx) + omx, (y0 - pdy) + omy, x0 + omx, y0 + omy, |
| (dx + x0) + mx, (dy + y0) + my, x0 + mx, y0 + my, miter); |
| |
| final double miterX = miter[0]; |
| final double miterY = miter[1]; |
| double lenSq = (miterX-x0)*(miterX-x0) + (miterY-y0)*(miterY-y0); |
| |
| // If the lines are parallel, lenSq will be either NaN or +inf |
| // (actually, I'm not sure if the latter is possible. The important |
| // thing is that -inf is not possible, because lenSq is a square). |
| // For both of those values, the comparison below will fail and |
| // no miter will be drawn, which is correct. |
| if (lenSq < miterLimitSq) { |
| emitLineTo(miterX, miterY, rev); |
| } |
| } |
| |
| @Override |
| public void moveTo(final double x0, final double y0) { |
| _moveTo(x0, y0, cOutCode); |
| // update starting point: |
| this.sx0 = x0; |
| this.sy0 = y0; |
| this.sdx = 1.0d; |
| this.sdy = 0.0d; |
| this.opened = false; |
| this.capStart = false; |
| |
| if (clipRect != null) { |
| final int outcode = DHelpers.outcode(x0, y0, clipRect); |
| this.cOutCode = outcode; |
| this.sOutCode = outcode; |
| } |
| } |
| |
| private void _moveTo(final double x0, final double y0, |
| final int outcode) |
| { |
| if (prev == MOVE_TO) { |
| this.cx0 = x0; |
| this.cy0 = y0; |
| } else { |
| if (prev == DRAWING_OP_TO) { |
| finish(outcode); |
| } |
| this.prev = MOVE_TO; |
| this.cx0 = x0; |
| this.cy0 = y0; |
| this.cdx = 1.0d; |
| this.cdy = 0.0d; |
| } |
| } |
| |
| @Override |
| public void lineTo(final double x1, final double y1) { |
| lineTo(x1, y1, false); |
| } |
| |
| private void lineTo(final double x1, final double y1, |
| final boolean force) |
| { |
| final int outcode0 = this.cOutCode; |
| |
| if (!force && clipRect != null) { |
| final int outcode1 = DHelpers.outcode(x1, y1, clipRect); |
| |
| // Should clip |
| final int orCode = (outcode0 | outcode1); |
| if (orCode != 0) { |
| final int sideCode = outcode0 & outcode1; |
| |
| // basic rejection criteria: |
| if (sideCode == 0) { |
| // ovelap clip: |
| if (subdivide) { |
| // avoid reentrance |
| subdivide = false; |
| // subdivide curve => callback with subdivided parts: |
| boolean ret = curveSplitter.splitLine(cx0, cy0, x1, y1, |
| orCode, this); |
| // reentrance is done: |
| subdivide = true; |
| if (ret) { |
| return; |
| } |
| } |
| // already subdivided so render it |
| } else { |
| this.cOutCode = outcode1; |
| _moveTo(x1, y1, outcode0); |
| opened = true; |
| return; |
| } |
| } |
| |
| this.cOutCode = outcode1; |
| } |
| |
| double dx = x1 - cx0; |
| double dy = y1 - cy0; |
| if (dx == 0.0d && dy == 0.0d) { |
| dx = 1.0d; |
| } |
| computeOffset(dx, dy, lineWidth2, offset0); |
| final double mx = offset0[0]; |
| final double my = offset0[1]; |
| |
| drawJoin(cdx, cdy, cx0, cy0, dx, dy, cmx, cmy, mx, my, outcode0); |
| |
| emitLineTo(cx0 + mx, cy0 + my); |
| emitLineTo( x1 + mx, y1 + my); |
| |
| emitLineToRev(cx0 - mx, cy0 - my); |
| emitLineToRev( x1 - mx, y1 - my); |
| |
| this.prev = DRAWING_OP_TO; |
| this.cx0 = x1; |
| this.cy0 = y1; |
| this.cdx = dx; |
| this.cdy = dy; |
| this.cmx = mx; |
| this.cmy = my; |
| } |
| |
| @Override |
| public void closePath() { |
| // distinguish empty path at all vs opened path ? |
| if (prev != DRAWING_OP_TO && !opened) { |
| if (prev == CLOSE) { |
| return; |
| } |
| emitMoveTo(cx0, cy0 - lineWidth2); |
| |
| this.sdx = 1.0d; |
| this.sdy = 0.0d; |
| this.cdx = 1.0d; |
| this.cdy = 0.0d; |
| |
| this.smx = 0.0d; |
| this.smy = -lineWidth2; |
| this.cmx = 0.0d; |
| this.cmy = -lineWidth2; |
| |
| finish(cOutCode); |
| return; |
| } |
| |
| // basic acceptance criteria |
| if ((sOutCode & cOutCode) == 0) { |
| if (cx0 != sx0 || cy0 != sy0) { |
| lineTo(sx0, sy0, true); |
| } |
| |
| drawJoin(cdx, cdy, cx0, cy0, sdx, sdy, cmx, cmy, smx, smy, sOutCode); |
| |
| emitLineTo(sx0 + smx, sy0 + smy); |
| |
| if (opened) { |
| emitLineTo(sx0 - smx, sy0 - smy); |
| } else { |
| emitMoveTo(sx0 - smx, sy0 - smy); |
| } |
| } |
| // Ignore caps like finish(false) |
| emitReverse(); |
| |
| this.prev = CLOSE; |
| |
| if (opened) { |
| // do not emit close |
| opened = false; |
| } else { |
| emitClose(); |
| } |
| } |
| |
| private void emitReverse() { |
| reverse.popAll(out); |
| } |
| |
| @Override |
| public void pathDone() { |
| if (prev == DRAWING_OP_TO) { |
| finish(cOutCode); |
| } |
| |
| out.pathDone(); |
| |
| // this shouldn't matter since this object won't be used |
| // after the call to this method. |
| this.prev = CLOSE; |
| |
| // Dispose this instance: |
| dispose(); |
| } |
| |
| private void finish(final int outcode) { |
| // Problem: impossible to guess if the path will be closed in advance |
| // i.e. if caps must be drawn or not ? |
| // Solution: use the ClosedPathDetector before Stroker to determine |
| // if the path is a closed path or not |
| if (!rdrCtx.closedPath) { |
| if (outcode == 0) { |
| // current point = end's cap: |
| if (capStyle == CAP_ROUND) { |
| drawRoundCap(cx0, cy0, cmx, cmy); |
| } else if (capStyle == CAP_SQUARE) { |
| emitLineTo(cx0 - cmy + cmx, cy0 + cmx + cmy); |
| emitLineTo(cx0 - cmy - cmx, cy0 + cmx - cmy); |
| } |
| } |
| emitReverse(); |
| |
| if (!capStart) { |
| capStart = true; |
| |
| if (sOutCode == 0) { |
| // starting point = initial cap: |
| if (capStyle == CAP_ROUND) { |
| drawRoundCap(sx0, sy0, -smx, -smy); |
| } else if (capStyle == CAP_SQUARE) { |
| emitLineTo(sx0 + smy - smx, sy0 - smx - smy); |
| emitLineTo(sx0 + smy + smx, sy0 - smx + smy); |
| } |
| } |
| } |
| } else { |
| emitReverse(); |
| } |
| emitClose(); |
| } |
| |
| private void emitMoveTo(final double x0, final double y0) { |
| out.moveTo(x0, y0); |
| } |
| |
| private void emitLineTo(final double x1, final double y1) { |
| out.lineTo(x1, y1); |
| } |
| |
| private void emitLineToRev(final double x1, final double y1) { |
| reverse.pushLine(x1, y1); |
| } |
| |
| private void emitLineTo(final double x1, final double y1, |
| final boolean rev) |
| { |
| if (rev) { |
| emitLineToRev(x1, y1); |
| } else { |
| emitLineTo(x1, y1); |
| } |
| } |
| |
| private void emitQuadTo(final double x1, final double y1, |
| final double x2, final double y2) |
| { |
| out.quadTo(x1, y1, x2, y2); |
| } |
| |
| private void emitQuadToRev(final double x0, final double y0, |
| final double x1, final double y1) |
| { |
| reverse.pushQuad(x0, y0, x1, y1); |
| } |
| |
| private void emitCurveTo(final double x1, final double y1, |
| final double x2, final double y2, |
| final double x3, final double y3) |
| { |
| out.curveTo(x1, y1, x2, y2, x3, y3); |
| } |
| |
| private void emitCurveToRev(final double x0, final double y0, |
| final double x1, final double y1, |
| final double x2, final double y2) |
| { |
| reverse.pushCubic(x0, y0, x1, y1, x2, y2); |
| } |
| |
| private void emitCurveTo(final double x0, final double y0, |
| final double x1, final double y1, |
| final double x2, final double y2, |
| final double x3, final double y3, final boolean rev) |
| { |
| if (rev) { |
| reverse.pushCubic(x0, y0, x1, y1, x2, y2); |
| } else { |
| out.curveTo(x1, y1, x2, y2, x3, y3); |
| } |
| } |
| |
| private void emitClose() { |
| out.closePath(); |
| } |
| |
| private void drawJoin(double pdx, double pdy, |
| double x0, double y0, |
| double dx, double dy, |
| double omx, double omy, |
| double mx, double my, |
| final int outcode) |
| { |
| if (prev != DRAWING_OP_TO) { |
| emitMoveTo(x0 + mx, y0 + my); |
| if (!opened) { |
| this.sdx = dx; |
| this.sdy = dy; |
| this.smx = mx; |
| this.smy = my; |
| } |
| } else { |
| final boolean cw = isCW(pdx, pdy, dx, dy); |
| if (outcode == 0) { |
| if (joinStyle == JOIN_MITER) { |
| drawMiter(pdx, pdy, x0, y0, dx, dy, omx, omy, mx, my, cw); |
| } else if (joinStyle == JOIN_ROUND) { |
| mayDrawRoundJoin(x0, y0, omx, omy, mx, my, cw); |
| } |
| } |
| emitLineTo(x0, y0, !cw); |
| } |
| prev = DRAWING_OP_TO; |
| } |
| |
| private static boolean within(final double x1, final double y1, |
| final double x2, final double y2, |
| final double err) |
| { |
| assert err > 0 : ""; |
| // compare taxicab distance. ERR will always be small, so using |
| // true distance won't give much benefit |
| return (DHelpers.within(x1, x2, err) && // we want to avoid calling Math.abs |
| DHelpers.within(y1, y2, err)); // this is just as good. |
| } |
| |
| private void getLineOffsets(final double x1, final double y1, |
| final double x2, final double y2, |
| final double[] left, final double[] right) |
| { |
| computeOffset(x2 - x1, y2 - y1, lineWidth2, offset0); |
| final double mx = offset0[0]; |
| final double my = offset0[1]; |
| left[0] = x1 + mx; |
| left[1] = y1 + my; |
| left[2] = x2 + mx; |
| left[3] = y2 + my; |
| |
| right[0] = x1 - mx; |
| right[1] = y1 - my; |
| right[2] = x2 - mx; |
| right[3] = y2 - my; |
| } |
| |
| private int computeOffsetCubic(final double[] pts, final int off, |
| final double[] leftOff, |
| final double[] 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 widen |
| // 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 double x1 = pts[off ], y1 = pts[off + 1]; |
| final double x2 = pts[off + 2], y2 = pts[off + 3]; |
| final double x3 = pts[off + 4], y3 = pts[off + 5]; |
| final double x4 = pts[off + 6], y4 = pts[off + 7]; |
| |
| double dx4 = x4 - x3; |
| double dy4 = y4 - y3; |
| double dx1 = x2 - x1; |
| double 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, 6.0d * Math.ulp(y2)); |
| final boolean p3eqp4 = within(x3, y3, x4, y4, 6.0d * Math.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 |
| double dotsq = (dx1 * dx4 + dy1 * dy4); |
| dotsq *= dotsq; |
| double l1sq = dx1 * dx1 + dy1 * dy1, l4sq = dx4 * dx4 + dy4 * dy4; |
| |
| if (DHelpers.within(dotsq, l1sq * l4sq, 4.0d * Math.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. |
| |
| double x = (x1 + 3.0d * (x2 + x3) + x4) / 8.0d; |
| double y = (y1 + 3.0d * (y2 + y3) + y4) / 8.0d; |
| // (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. |
| double 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, offset0); |
| computeOffset(dxm, dym, lineWidth2, offset1); |
| computeOffset(dx4, dy4, lineWidth2, offset2); |
| double x1p = x1 + offset0[0]; // start |
| double y1p = y1 + offset0[1]; // point |
| double xi = x + offset1[0]; // interpolation |
| double yi = y + offset1[1]; // point |
| double x4p = x4 + offset2[0]; // end |
| double y4p = y4 + offset2[1]; // point |
| |
| double invdet43 = 4.0d / (3.0d * (dx1 * dy4 - dy1 * dx4)); |
| |
| double two_pi_m_p1_m_p4x = 2.0d * xi - x1p - x4p; |
| double two_pi_m_p1_m_p4y = 2.0d * yi - y1p - y4p; |
| double c1 = invdet43 * (dy4 * two_pi_m_p1_m_p4x - dx4 * two_pi_m_p1_m_p4y); |
| double c2 = invdet43 * (dx1 * two_pi_m_p1_m_p4y - dy1 * two_pi_m_p1_m_p4x); |
| |
| double 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 - offset0[0]; y1p = y1 - offset0[1]; |
| xi = xi - 2.0d * offset1[0]; yi = yi - 2.0d * offset1[1]; |
| x4p = x4 - offset2[0]; y4p = y4 - offset2[1]; |
| |
| two_pi_m_p1_m_p4x = 2.0d * xi - x1p - x4p; |
| two_pi_m_p1_m_p4y = 2.0d * 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; |
| } |
| |
| // compute offset curves using bezier spline through t=0.5 (i.e. |
| // ComputedCurve(0.5) == IdealParallelCurve(0.5)) |
| // return the kind of curve in the right and left arrays. |
| private int computeOffsetQuad(final double[] pts, final int off, |
| final double[] leftOff, |
| final double[] rightOff) |
| { |
| final double x1 = pts[off ], y1 = pts[off + 1]; |
| final double x2 = pts[off + 2], y2 = pts[off + 3]; |
| final double x3 = pts[off + 4], y3 = pts[off + 5]; |
| |
| final double dx3 = x3 - x2; |
| final double dy3 = y3 - y2; |
| final double dx1 = x2 - x1; |
| final double dy1 = y2 - y1; |
| |
| // 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 widen |
| // 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. |
| |
| // if p1 == p2 && p3 == p4: draw line from p1->p4, unless p1 == p4, |
| // in which case ignore. |
| final boolean p1eqp2 = within(x1, y1, x2, y2, 6.0d * Math.ulp(y2)); |
| final boolean p2eqp3 = within(x2, y2, x3, y3, 6.0d * Math.ulp(y3)); |
| |
| if (p1eqp2 || p2eqp3) { |
| getLineOffsets(x1, y1, x3, y3, leftOff, rightOff); |
| return 4; |
| } |
| |
| // if p2-p1 and p4-p3 are parallel, that must mean this curve is a line |
| double dotsq = (dx1 * dx3 + dy1 * dy3); |
| dotsq *= dotsq; |
| double l1sq = dx1 * dx1 + dy1 * dy1, l3sq = dx3 * dx3 + dy3 * dy3; |
| |
| if (DHelpers.within(dotsq, l1sq * l3sq, 4.0d * Math.ulp(dotsq))) { |
| getLineOffsets(x1, y1, x3, y3, leftOff, rightOff); |
| return 4; |
| } |
| |
| // 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, offset0); |
| computeOffset(dx3, dy3, lineWidth2, offset1); |
| |
| double x1p = x1 + offset0[0]; // start |
| double y1p = y1 + offset0[1]; // point |
| double x3p = x3 + offset1[0]; // end |
| double y3p = y3 + offset1[1]; // point |
| safeComputeMiter(x1p, y1p, x1p+dx1, y1p+dy1, x3p, y3p, x3p-dx3, y3p-dy3, leftOff); |
| leftOff[0] = x1p; leftOff[1] = y1p; |
| leftOff[4] = x3p; leftOff[5] = y3p; |
| |
| x1p = x1 - offset0[0]; y1p = y1 - offset0[1]; |
| x3p = x3 - offset1[0]; y3p = y3 - offset1[1]; |
| safeComputeMiter(x1p, y1p, x1p+dx1, y1p+dy1, x3p, y3p, x3p-dx3, y3p-dy3, rightOff); |
| rightOff[0] = x1p; rightOff[1] = y1p; |
| rightOff[4] = x3p; rightOff[5] = y3p; |
| return 6; |
| } |
| |
| @Override |
| public void curveTo(final double x1, final double y1, |
| final double x2, final double y2, |
| final double x3, final double y3) |
| { |
| final int outcode0 = this.cOutCode; |
| |
| if (clipRect != null) { |
| final int outcode1 = DHelpers.outcode(x1, y1, clipRect); |
| final int outcode2 = DHelpers.outcode(x2, y2, clipRect); |
| final int outcode3 = DHelpers.outcode(x3, y3, clipRect); |
| |
| // Should clip |
| final int orCode = (outcode0 | outcode1 | outcode2 | outcode3); |
| if (orCode != 0) { |
| final int sideCode = outcode0 & outcode1 & outcode2 & outcode3; |
| |
| // basic rejection criteria: |
| if (sideCode == 0) { |
| // ovelap clip: |
| if (subdivide) { |
| // avoid reentrance |
| subdivide = false; |
| // subdivide curve => callback with subdivided parts: |
| boolean ret = curveSplitter.splitCurve(cx0, cy0, x1, y1, |
| x2, y2, x3, y3, |
| orCode, this); |
| // reentrance is done: |
| subdivide = true; |
| if (ret) { |
| return; |
| } |
| } |
| // already subdivided so render it |
| } else { |
| this.cOutCode = outcode3; |
| _moveTo(x3, y3, outcode0); |
| opened = true; |
| return; |
| } |
| } |
| |
| this.cOutCode = outcode3; |
| } |
| _curveTo(x1, y1, x2, y2, x3, y3, outcode0); |
| } |
| |
| private void _curveTo(final double x1, final double y1, |
| final double x2, final double y2, |
| final double x3, final double y3, |
| final int outcode0) |
| { |
| // need these so we can update the state at the end of this method |
| double dxs = x1 - cx0; |
| double dys = y1 - cy0; |
| double dxf = x3 - x2; |
| double dyf = y3 - y2; |
| |
| if ((dxs == 0.0d) && (dys == 0.0d)) { |
| dxs = x2 - cx0; |
| dys = y2 - cy0; |
| if ((dxs == 0.0d) && (dys == 0.0d)) { |
| dxs = x3 - cx0; |
| dys = y3 - cy0; |
| } |
| } |
| if ((dxf == 0.0d) && (dyf == 0.0d)) { |
| dxf = x3 - x1; |
| dyf = y3 - y1; |
| if ((dxf == 0.0d) && (dyf == 0.0d)) { |
| dxf = x3 - cx0; |
| dyf = y3 - cy0; |
| } |
| } |
| if ((dxs == 0.0d) && (dys == 0.0d)) { |
| // this happens if the "curve" is just a point |
| // fix outcode0 for lineTo() call: |
| if (clipRect != null) { |
| this.cOutCode = outcode0; |
| } |
| lineTo(cx0, cy0); |
| return; |
| } |
| |
| // if these vectors are too small, normalize them, to avoid future |
| // precision problems. |
| if (Math.abs(dxs) < 0.1d && Math.abs(dys) < 0.1d) { |
| final double len = Math.sqrt(dxs * dxs + dys * dys); |
| dxs /= len; |
| dys /= len; |
| } |
| if (Math.abs(dxf) < 0.1d && Math.abs(dyf) < 0.1d) { |
| final double len = Math.sqrt(dxf * dxf + dyf * dyf); |
| dxf /= len; |
| dyf /= len; |
| } |
| |
| computeOffset(dxs, dys, lineWidth2, offset0); |
| drawJoin(cdx, cdy, cx0, cy0, dxs, dys, cmx, cmy, offset0[0], offset0[1], outcode0); |
| |
| int nSplits = 0; |
| final double[] mid; |
| final double[] l = lp; |
| |
| if (monotonize) { |
| // monotonize curve: |
| final CurveBasicMonotonizer monotonizer |
| = rdrCtx.monotonizer.curve(cx0, cy0, x1, y1, x2, y2, x3, y3); |
| |
| nSplits = monotonizer.nbSplits; |
| mid = monotonizer.middle; |
| } else { |
| // use left instead: |
| mid = l; |
| mid[0] = cx0; mid[1] = cy0; |
| mid[2] = x1; mid[3] = y1; |
| mid[4] = x2; mid[5] = y2; |
| mid[6] = x3; mid[7] = y3; |
| } |
| final double[] r = rp; |
| |
| int kind = 0; |
| for (int i = 0, off = 0; i <= nSplits; i++, off += 6) { |
| kind = computeOffsetCubic(mid, off, l, r); |
| |
| emitLineTo(l[0], l[1]); |
| |
| switch(kind) { |
| case 8: |
| emitCurveTo(l[2], l[3], l[4], l[5], l[6], l[7]); |
| emitCurveToRev(r[0], r[1], r[2], r[3], r[4], r[5]); |
| break; |
| case 4: |
| emitLineTo(l[2], l[3]); |
| emitLineToRev(r[0], r[1]); |
| break; |
| default: |
| } |
| emitLineToRev(r[kind - 2], r[kind - 1]); |
| } |
| |
| this.prev = DRAWING_OP_TO; |
| this.cx0 = x3; |
| this.cy0 = y3; |
| this.cdx = dxf; |
| this.cdy = dyf; |
| this.cmx = (l[kind - 2] - r[kind - 2]) / 2.0d; |
| this.cmy = (l[kind - 1] - r[kind - 1]) / 2.0d; |
| } |
| |
| @Override |
| public void quadTo(final double x1, final double y1, |
| final double x2, final double y2) |
| { |
| final int outcode0 = this.cOutCode; |
| |
| if (clipRect != null) { |
| final int outcode1 = DHelpers.outcode(x1, y1, clipRect); |
| final int outcode2 = DHelpers.outcode(x2, y2, clipRect); |
| |
| // Should clip |
| final int orCode = (outcode0 | outcode1 | outcode2); |
| if (orCode != 0) { |
| final int sideCode = outcode0 & outcode1 & outcode2; |
| |
| // basic rejection criteria: |
| if (sideCode == 0) { |
| // ovelap clip: |
| if (subdivide) { |
| // avoid reentrance |
| subdivide = false; |
| // subdivide curve => call lineTo() with subdivided curves: |
| boolean ret = curveSplitter.splitQuad(cx0, cy0, x1, y1, |
| x2, y2, orCode, this); |
| // reentrance is done: |
| subdivide = true; |
| if (ret) { |
| return; |
| } |
| } |
| // already subdivided so render it |
| } else { |
| this.cOutCode = outcode2; |
| _moveTo(x2, y2, outcode0); |
| opened = true; |
| return; |
| } |
| } |
| |
| this.cOutCode = outcode2; |
| } |
| _quadTo(x1, y1, x2, y2, outcode0); |
| } |
| |
| private void _quadTo(final double x1, final double y1, |
| final double x2, final double y2, |
| final int outcode0) |
| { |
| // need these so we can update the state at the end of this method |
| double dxs = x1 - cx0; |
| double dys = y1 - cy0; |
| double dxf = x2 - x1; |
| double dyf = y2 - y1; |
| |
| if (((dxs == 0.0d) && (dys == 0.0d)) || ((dxf == 0.0d) && (dyf == 0.0d))) { |
| dxs = dxf = x2 - cx0; |
| dys = dyf = y2 - cy0; |
| } |
| if ((dxs == 0.0d) && (dys == 0.0d)) { |
| // this happens if the "curve" is just a point |
| // fix outcode0 for lineTo() call: |
| if (clipRect != null) { |
| this.cOutCode = outcode0; |
| } |
| lineTo(cx0, cy0); |
| return; |
| } |
| // if these vectors are too small, normalize them, to avoid future |
| // precision problems. |
| if (Math.abs(dxs) < 0.1d && Math.abs(dys) < 0.1d) { |
| final double len = Math.sqrt(dxs * dxs + dys * dys); |
| dxs /= len; |
| dys /= len; |
| } |
| if (Math.abs(dxf) < 0.1d && Math.abs(dyf) < 0.1d) { |
| final double len = Math.sqrt(dxf * dxf + dyf * dyf); |
| dxf /= len; |
| dyf /= len; |
| } |
| computeOffset(dxs, dys, lineWidth2, offset0); |
| drawJoin(cdx, cdy, cx0, cy0, dxs, dys, cmx, cmy, offset0[0], offset0[1], outcode0); |
| |
| int nSplits = 0; |
| final double[] mid; |
| final double[] l = lp; |
| |
| if (monotonize) { |
| // monotonize quad: |
| final CurveBasicMonotonizer monotonizer |
| = rdrCtx.monotonizer.quad(cx0, cy0, x1, y1, x2, y2); |
| |
| nSplits = monotonizer.nbSplits; |
| mid = monotonizer.middle; |
| } else { |
| // use left instead: |
| mid = l; |
| mid[0] = cx0; mid[1] = cy0; |
| mid[2] = x1; mid[3] = y1; |
| mid[4] = x2; mid[5] = y2; |
| } |
| final double[] r = rp; |
| |
| int kind = 0; |
| for (int i = 0, off = 0; i <= nSplits; i++, off += 4) { |
| kind = computeOffsetQuad(mid, off, l, r); |
| |
| emitLineTo(l[0], l[1]); |
| |
| switch(kind) { |
| case 6: |
| emitQuadTo(l[2], l[3], l[4], l[5]); |
| emitQuadToRev(r[0], r[1], r[2], r[3]); |
| break; |
| case 4: |
| emitLineTo(l[2], l[3]); |
| emitLineToRev(r[0], r[1]); |
| break; |
| default: |
| } |
| emitLineToRev(r[kind - 2], r[kind - 1]); |
| } |
| |
| this.prev = DRAWING_OP_TO; |
| this.cx0 = x2; |
| this.cy0 = y2; |
| this.cdx = dxf; |
| this.cdy = dyf; |
| this.cmx = (l[kind - 2] - r[kind - 2]) / 2.0d; |
| this.cmy = (l[kind - 1] - r[kind - 1]) / 2.0d; |
| } |
| |
| @Override public long getNativeConsumer() { |
| throw new InternalError("Stroker doesn't use a native consumer"); |
| } |
| } |
