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1395 lines
49 KiB
Java
1395 lines
49 KiB
Java
/*
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* Copyright (c) 2007, 2015, Oracle and/or its affiliates. All rights reserved.
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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*
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* This code is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License version 2 only, as
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* published by the Free Software Foundation. Oracle designates this
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* particular file as subject to the "Classpath" exception as provided
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* by Oracle in the LICENSE file that accompanied this code.
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*
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* This code is distributed in the hope that it will be useful, but WITHOUT
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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* version 2 for more details (a copy is included in the LICENSE file that
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* accompanied this code).
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*
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* You should have received a copy of the GNU General Public License version
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* 2 along with this work; if not, write to the Free Software Foundation,
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* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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*
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* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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* or visit www.oracle.com if you need additional information or have any
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* questions.
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*/
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package sun.java2d.marlin;
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import java.util.Arrays;
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import static java.lang.Math.ulp;
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import static java.lang.Math.sqrt;
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import sun.awt.geom.PathConsumer2D;
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import sun.java2d.marlin.Curve.BreakPtrIterator;
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// TODO: some of the arithmetic here is too verbose and prone to hard to
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// debug typos. We should consider making a small Point/Vector class that
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// has methods like plus(Point), minus(Point), dot(Point), cross(Point)and such
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final class Stroker implements PathConsumer2D, MarlinConst {
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private static final int MOVE_TO = 0;
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private static final int DRAWING_OP_TO = 1; // ie. curve, line, or quad
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private static final int CLOSE = 2;
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/**
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* Constant value for join style.
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*/
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public static final int JOIN_MITER = 0;
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/**
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* Constant value for join style.
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*/
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public static final int JOIN_ROUND = 1;
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/**
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* Constant value for join style.
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*/
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public static final int JOIN_BEVEL = 2;
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/**
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* Constant value for end cap style.
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*/
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public static final int CAP_BUTT = 0;
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/**
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* Constant value for end cap style.
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*/
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public static final int CAP_ROUND = 1;
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/**
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* Constant value for end cap style.
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*/
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public static final int CAP_SQUARE = 2;
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// pisces used to use fixed point arithmetic with 16 decimal digits. I
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// didn't want to change the values of the constant below when I converted
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// it to floating point, so that's why the divisions by 2^16 are there.
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private static final float ROUND_JOIN_THRESHOLD = 1000/65536f;
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private static final float C = 0.5522847498307933f;
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private static final int MAX_N_CURVES = 11;
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private PathConsumer2D out;
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private int capStyle;
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private int joinStyle;
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private float lineWidth2;
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private float invHalfLineWidth2Sq;
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private final float[] offset0 = new float[2];
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private final float[] offset1 = new float[2];
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private final float[] offset2 = new float[2];
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private final float[] miter = new float[2];
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private float miterLimitSq;
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private int prev;
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// The starting point of the path, and the slope there.
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private float sx0, sy0, sdx, sdy;
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// the current point and the slope there.
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private float cx0, cy0, cdx, cdy; // c stands for current
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// vectors that when added to (sx0,sy0) and (cx0,cy0) respectively yield the
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// first and last points on the left parallel path. Since this path is
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// parallel, it's slope at any point is parallel to the slope of the
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// original path (thought they may have different directions), so these
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// could be computed from sdx,sdy and cdx,cdy (and vice versa), but that
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// would be error prone and hard to read, so we keep these anyway.
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private float smx, smy, cmx, cmy;
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private final PolyStack reverse;
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// This is where the curve to be processed is put. We give it
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// enough room to store 2 curves: one for the current subdivision, the
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// other for the rest of the curve.
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private final float[] middle = new float[2 * 8];
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private final float[] lp = new float[8];
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private final float[] rp = new float[8];
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private final float[] subdivTs = new float[MAX_N_CURVES - 1];
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// per-thread renderer context
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final RendererContext rdrCtx;
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// dirty curve
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final Curve curve;
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/**
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* Constructs a <code>Stroker</code>.
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* @param rdrCtx per-thread renderer context
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*/
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Stroker(final RendererContext rdrCtx) {
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this.rdrCtx = rdrCtx;
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this.reverse = new PolyStack(rdrCtx);
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this.curve = rdrCtx.curve;
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}
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/**
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* Inits the <code>Stroker</code>.
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*
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* @param pc2d an output <code>PathConsumer2D</code>.
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* @param lineWidth the desired line width in pixels
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* @param capStyle the desired end cap style, one of
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* <code>CAP_BUTT</code>, <code>CAP_ROUND</code> or
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* <code>CAP_SQUARE</code>.
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* @param joinStyle the desired line join style, one of
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* <code>JOIN_MITER</code>, <code>JOIN_ROUND</code> or
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* <code>JOIN_BEVEL</code>.
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* @param miterLimit the desired miter limit
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* @return this instance
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*/
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Stroker init(PathConsumer2D pc2d,
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float lineWidth,
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int capStyle,
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int joinStyle,
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float miterLimit)
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{
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this.out = pc2d;
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this.lineWidth2 = lineWidth / 2f;
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this.invHalfLineWidth2Sq = 1f / (2f * lineWidth2 * lineWidth2);
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this.capStyle = capStyle;
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this.joinStyle = joinStyle;
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float limit = miterLimit * lineWidth2;
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this.miterLimitSq = limit * limit;
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this.prev = CLOSE;
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rdrCtx.stroking = 1;
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return this; // fluent API
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}
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/**
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* Disposes this stroker:
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* clean up before reusing this instance
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*/
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void dispose() {
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reverse.dispose();
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if (doCleanDirty) {
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// Force zero-fill dirty arrays:
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Arrays.fill(offset0, 0f);
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Arrays.fill(offset1, 0f);
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Arrays.fill(offset2, 0f);
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Arrays.fill(miter, 0f);
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Arrays.fill(middle, 0f);
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Arrays.fill(lp, 0f);
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Arrays.fill(rp, 0f);
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Arrays.fill(subdivTs, 0f);
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}
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}
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private static void computeOffset(final float lx, final float ly,
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final float w, final float[] m)
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{
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float len = lx*lx + ly*ly;
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if (len == 0f) {
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m[0] = 0f;
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m[1] = 0f;
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} else {
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len = (float) sqrt(len);
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m[0] = (ly * w) / len;
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m[1] = -(lx * w) / len;
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}
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}
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// Returns true if the vectors (dx1, dy1) and (dx2, dy2) are
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// clockwise (if dx1,dy1 needs to be rotated clockwise to close
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// the smallest angle between it and dx2,dy2).
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// This is equivalent to detecting whether a point q is on the right side
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// of a line passing through points p1, p2 where p2 = p1+(dx1,dy1) and
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// q = p2+(dx2,dy2), which is the same as saying p1, p2, q are in a
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// clockwise order.
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// NOTE: "clockwise" here assumes coordinates with 0,0 at the bottom left.
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private static boolean isCW(final float dx1, final float dy1,
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final float dx2, final float dy2)
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{
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return dx1 * dy2 <= dy1 * dx2;
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}
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private void drawRoundJoin(float x, float y,
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float omx, float omy, float mx, float my,
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boolean rev,
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float threshold)
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{
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if ((omx == 0 && omy == 0) || (mx == 0 && my == 0)) {
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return;
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}
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float domx = omx - mx;
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float domy = omy - my;
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float len = domx*domx + domy*domy;
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if (len < threshold) {
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return;
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}
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if (rev) {
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omx = -omx;
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omy = -omy;
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mx = -mx;
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my = -my;
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}
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drawRoundJoin(x, y, omx, omy, mx, my, rev);
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}
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private void drawRoundJoin(float cx, float cy,
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float omx, float omy,
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float mx, float my,
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boolean rev)
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{
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// The sign of the dot product of mx,my and omx,omy is equal to the
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// the sign of the cosine of ext
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// (ext is the angle between omx,omy and mx,my).
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final float cosext = omx * mx + omy * my;
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// If it is >=0, we know that abs(ext) is <= 90 degrees, so we only
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// need 1 curve to approximate the circle section that joins omx,omy
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// and mx,my.
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final int numCurves = (cosext >= 0f) ? 1 : 2;
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switch (numCurves) {
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case 1:
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drawBezApproxForArc(cx, cy, omx, omy, mx, my, rev);
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break;
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case 2:
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// we need to split the arc into 2 arcs spanning the same angle.
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// The point we want will be one of the 2 intersections of the
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// perpendicular bisector of the chord (omx,omy)->(mx,my) and the
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// circle. We could find this by scaling the vector
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// (omx+mx, omy+my)/2 so that it has length=lineWidth2 (and thus lies
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// on the circle), but that can have numerical problems when the angle
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// between omx,omy and mx,my is close to 180 degrees. So we compute a
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// normal of (omx,omy)-(mx,my). This will be the direction of the
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// perpendicular bisector. To get one of the intersections, we just scale
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// this vector that its length is lineWidth2 (this works because the
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// perpendicular bisector goes through the origin). This scaling doesn't
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// have numerical problems because we know that lineWidth2 divided by
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// this normal's length is at least 0.5 and at most sqrt(2)/2 (because
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// we know the angle of the arc is > 90 degrees).
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float nx = my - omy, ny = omx - mx;
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float nlen = (float) sqrt(nx*nx + ny*ny);
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float scale = lineWidth2/nlen;
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float mmx = nx * scale, mmy = ny * scale;
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// if (isCW(omx, omy, mx, my) != isCW(mmx, mmy, mx, my)) then we've
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// computed the wrong intersection so we get the other one.
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// The test above is equivalent to if (rev).
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if (rev) {
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mmx = -mmx;
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mmy = -mmy;
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}
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drawBezApproxForArc(cx, cy, omx, omy, mmx, mmy, rev);
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drawBezApproxForArc(cx, cy, mmx, mmy, mx, my, rev);
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break;
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default:
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}
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}
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// the input arc defined by omx,omy and mx,my must span <= 90 degrees.
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private void drawBezApproxForArc(final float cx, final float cy,
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final float omx, final float omy,
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final float mx, final float my,
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boolean rev)
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{
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final float cosext2 = (omx * mx + omy * my) * invHalfLineWidth2Sq;
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// check round off errors producing cos(ext) > 1 and a NaN below
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// cos(ext) == 1 implies colinear segments and an empty join anyway
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if (cosext2 >= 0.5f) {
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// just return to avoid generating a flat curve:
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return;
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}
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// cv is the length of P1-P0 and P2-P3 divided by the radius of the arc
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// (so, cv assumes the arc has radius 1). P0, P1, P2, P3 are the points that
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// define the bezier curve we're computing.
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// It is computed using the constraints that P1-P0 and P3-P2 are parallel
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// to the arc tangents at the endpoints, and that |P1-P0|=|P3-P2|.
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float cv = (float) ((4.0 / 3.0) * sqrt(0.5 - cosext2) /
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(1.0 + sqrt(cosext2 + 0.5)));
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// if clockwise, we need to negate cv.
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if (rev) { // rev is equivalent to isCW(omx, omy, mx, my)
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cv = -cv;
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}
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final float x1 = cx + omx;
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final float y1 = cy + omy;
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final float x2 = x1 - cv * omy;
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final float y2 = y1 + cv * omx;
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final float x4 = cx + mx;
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final float y4 = cy + my;
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final float x3 = x4 + cv * my;
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final float y3 = y4 - cv * mx;
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emitCurveTo(x1, y1, x2, y2, x3, y3, x4, y4, rev);
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}
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private void drawRoundCap(float cx, float cy, float mx, float my) {
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emitCurveTo(cx+mx-C*my, cy+my+C*mx,
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cx-my+C*mx, cy+mx+C*my,
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cx-my, cy+mx);
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emitCurveTo(cx-my-C*mx, cy+mx-C*my,
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cx-mx-C*my, cy-my+C*mx,
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cx-mx, cy-my);
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}
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// Put the intersection point of the lines (x0, y0) -> (x1, y1)
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// and (x0p, y0p) -> (x1p, y1p) in m[off] and m[off+1].
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// If the lines are parallel, it will put a non finite number in m.
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private static void computeIntersection(final float x0, final float y0,
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final float x1, final float y1,
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final float x0p, final float y0p,
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final float x1p, final float y1p,
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final float[] m, int off)
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{
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float x10 = x1 - x0;
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float y10 = y1 - y0;
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float x10p = x1p - x0p;
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float y10p = y1p - y0p;
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float den = x10*y10p - x10p*y10;
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float t = x10p*(y0-y0p) - y10p*(x0-x0p);
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t /= den;
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m[off++] = x0 + t*x10;
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m[off] = y0 + t*y10;
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}
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private void drawMiter(final float pdx, final float pdy,
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final float x0, final float y0,
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final float dx, final float dy,
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float omx, float omy, float mx, float my,
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boolean rev)
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{
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if ((mx == omx && my == omy) ||
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(pdx == 0f && pdy == 0f) ||
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(dx == 0f && dy == 0f))
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{
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return;
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}
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if (rev) {
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omx = -omx;
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omy = -omy;
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mx = -mx;
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my = -my;
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}
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computeIntersection((x0 - pdx) + omx, (y0 - pdy) + omy, x0 + omx, y0 + omy,
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(dx + x0) + mx, (dy + y0) + my, x0 + mx, y0 + my,
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miter, 0);
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final float miterX = miter[0];
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final float miterY = miter[1];
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float lenSq = (miterX-x0)*(miterX-x0) + (miterY-y0)*(miterY-y0);
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// If the lines are parallel, lenSq will be either NaN or +inf
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// (actually, I'm not sure if the latter is possible. The important
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// thing is that -inf is not possible, because lenSq is a square).
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// For both of those values, the comparison below will fail and
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// no miter will be drawn, which is correct.
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if (lenSq < miterLimitSq) {
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emitLineTo(miterX, miterY, rev);
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}
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}
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@Override
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public void moveTo(float x0, float y0) {
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if (prev == DRAWING_OP_TO) {
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finish();
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}
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this.sx0 = this.cx0 = x0;
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this.sy0 = this.cy0 = y0;
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this.cdx = this.sdx = 1;
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this.cdy = this.sdy = 0;
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this.prev = MOVE_TO;
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}
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@Override
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public void lineTo(float x1, float y1) {
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float dx = x1 - cx0;
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float dy = y1 - cy0;
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if (dx == 0f && dy == 0f) {
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dx = 1f;
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}
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computeOffset(dx, dy, lineWidth2, offset0);
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final float mx = offset0[0];
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final float my = offset0[1];
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drawJoin(cdx, cdy, cx0, cy0, dx, dy, cmx, cmy, mx, my);
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emitLineTo(cx0 + mx, cy0 + my);
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emitLineTo( x1 + mx, y1 + my);
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emitLineToRev(cx0 - mx, cy0 - my);
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emitLineToRev( x1 - mx, y1 - my);
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this.cmx = mx;
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this.cmy = my;
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this.cdx = dx;
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this.cdy = dy;
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this.cx0 = x1;
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this.cy0 = y1;
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this.prev = DRAWING_OP_TO;
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}
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@Override
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public void closePath() {
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if (prev != DRAWING_OP_TO) {
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if (prev == CLOSE) {
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return;
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}
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emitMoveTo(cx0, cy0 - lineWidth2);
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this.cmx = this.smx = 0;
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this.cmy = this.smy = -lineWidth2;
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this.cdx = this.sdx = 1;
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this.cdy = this.sdy = 0;
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finish();
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return;
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}
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if (cx0 != sx0 || cy0 != sy0) {
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lineTo(sx0, sy0);
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}
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drawJoin(cdx, cdy, cx0, cy0, sdx, sdy, cmx, cmy, smx, smy);
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emitLineTo(sx0 + smx, sy0 + smy);
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emitMoveTo(sx0 - smx, sy0 - smy);
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emitReverse();
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this.prev = CLOSE;
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emitClose();
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}
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private void emitReverse() {
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reverse.popAll(out);
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}
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@Override
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public void pathDone() {
|
|
if (prev == DRAWING_OP_TO) {
|
|
finish();
|
|
}
|
|
|
|
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() {
|
|
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 (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);
|
|
}
|
|
|
|
emitClose();
|
|
}
|
|
|
|
private void emitMoveTo(final float x0, final float y0) {
|
|
out.moveTo(x0, y0);
|
|
}
|
|
|
|
private void emitLineTo(final float x1, final float y1) {
|
|
out.lineTo(x1, y1);
|
|
}
|
|
|
|
private void emitLineToRev(final float x1, final float y1) {
|
|
reverse.pushLine(x1, y1);
|
|
}
|
|
|
|
private void emitLineTo(final float x1, final float y1,
|
|
final boolean rev)
|
|
{
|
|
if (rev) {
|
|
emitLineToRev(x1, y1);
|
|
} else {
|
|
emitLineTo(x1, y1);
|
|
}
|
|
}
|
|
|
|
private void emitQuadTo(final float x1, final float y1,
|
|
final float x2, final float y2)
|
|
{
|
|
out.quadTo(x1, y1, x2, y2);
|
|
}
|
|
|
|
private void emitQuadToRev(final float x0, final float y0,
|
|
final float x1, final float y1)
|
|
{
|
|
reverse.pushQuad(x0, y0, x1, y1);
|
|
}
|
|
|
|
private void emitCurveTo(final float x1, final float y1,
|
|
final float x2, final float y2,
|
|
final float x3, final float y3)
|
|
{
|
|
out.curveTo(x1, y1, x2, y2, x3, y3);
|
|
}
|
|
|
|
private void emitCurveToRev(final float x0, final float y0,
|
|
final float x1, final float y1,
|
|
final float x2, final float y2)
|
|
{
|
|
reverse.pushCubic(x0, y0, x1, y1, x2, y2);
|
|
}
|
|
|
|
private void emitCurveTo(final float x0, final float y0,
|
|
final float x1, final float y1,
|
|
final float x2, final float y2,
|
|
final float x3, final float 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(float pdx, float pdy,
|
|
float x0, float y0,
|
|
float dx, float dy,
|
|
float omx, float omy,
|
|
float mx, float my)
|
|
{
|
|
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, offset0);
|
|
final float mx = offset0[0];
|
|
final float 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(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, 6f * ulp(y2));
|
|
final boolean p3eqp4 = within(x3,y3,x4,y4, 6f * 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;
|
|
float l1sq = dx1 * dx1 + dy1 * dy1, l4sq = dx4 * dx4 + dy4 * dy4;
|
|
if (Helpers.within(dotsq, l1sq * l4sq, 4f * 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 = (x1 + 3f * (x2 + x3) + x4) / 8f;
|
|
float y = (y1 + 3f * (y2 + y3) + y4) / 8f;
|
|
// (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, offset0);
|
|
computeOffset(dxm, dym, lineWidth2, offset1);
|
|
computeOffset(dx4, dy4, lineWidth2, offset2);
|
|
float x1p = x1 + offset0[0]; // start
|
|
float y1p = y1 + offset0[1]; // point
|
|
float xi = x + offset1[0]; // interpolation
|
|
float yi = y + offset1[1]; // point
|
|
float x4p = x4 + offset2[0]; // end
|
|
float y4p = y4 + offset2[1]; // point
|
|
|
|
float invdet43 = 4f / (3f * (dx1 * dy4 - dy1 * dx4));
|
|
|
|
float two_pi_m_p1_m_p4x = 2f * xi - x1p - x4p;
|
|
float two_pi_m_p1_m_p4y = 2f * 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 - offset0[0]; y1p = y1 - offset0[1];
|
|
xi = xi - 2f * offset1[0]; yi = yi - 2f * offset1[1];
|
|
x4p = x4 - offset2[0]; y4p = y4 - offset2[1];
|
|
|
|
two_pi_m_p1_m_p4x = 2f * xi - x1p - x4p;
|
|
two_pi_m_p1_m_p4y = 2f * 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, offset0);
|
|
computeOffset(dx3, dy3, lineWidth2, offset1);
|
|
|
|
leftOff[0] = x1 + offset0[0]; leftOff[1] = y1 + offset0[1];
|
|
leftOff[4] = x3 + offset1[0]; leftOff[5] = y3 + offset1[1];
|
|
rightOff[0] = x1 - offset0[0]; rightOff[1] = y1 - offset0[1];
|
|
rightOff[4] = x3 - offset1[0]; rightOff[5] = y3 - offset1[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] = 2f * x2 - cx;
|
|
leftOff[3] = 2f * y2 - cy;
|
|
return 6;
|
|
}
|
|
|
|
// rightOff[2,3] = (x2,y2) - ((left_x2, left_y2) - (x2, y2))
|
|
// == 2*(x2, y2) - (left_x2, left_y2)
|
|
rightOff[2] = 2f * x2 - cx;
|
|
rightOff[3] = 2f * y2 - cy;
|
|
return 6;
|
|
}
|
|
|
|
private static boolean isFinite(float x) {
|
|
return (Float.NEGATIVE_INFINITY < x && x < Float.POSITIVE_INFINITY);
|
|
}
|
|
|
|
// 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, offset0);
|
|
final float mx = offset0[0];
|
|
final float my = offset0[1];
|
|
drawJoin(cdx, cdy, cx0, cy0, dxs, dys, cmx, cmy, mx, my);
|
|
|
|
int nSplits = findSubdivPoints(curve, middle, subdivTs, type, lineWidth2);
|
|
|
|
int kind = 0;
|
|
BreakPtrIterator 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[2], lp[3], lp[4], lp[5], lp[6], lp[7]);
|
|
emitCurveToRev(rp[0], rp[1], rp[2], rp[3], rp[4], rp[5]);
|
|
break;
|
|
case 6:
|
|
emitQuadTo(lp[2], lp[3], lp[4], lp[5]);
|
|
emitQuadToRev(rp[0], rp[1], rp[2], rp[3]);
|
|
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 int findSubdivPoints(final Curve c, 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;
|
|
default:
|
|
}
|
|
} 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)
|
|
{
|
|
final float[] mid = middle;
|
|
|
|
mid[0] = cx0; mid[1] = cy0;
|
|
mid[2] = x1; mid[3] = y1;
|
|
mid[4] = x2; mid[5] = y2;
|
|
mid[6] = x3; mid[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 = mid[6], yf = mid[7];
|
|
float dxs = mid[2] - mid[0];
|
|
float dys = mid[3] - mid[1];
|
|
float dxf = mid[6] - mid[4];
|
|
float dyf = mid[7] - mid[5];
|
|
|
|
boolean p1eqp2 = (dxs == 0f && dys == 0f);
|
|
boolean p3eqp4 = (dxf == 0f && dyf == 0f);
|
|
if (p1eqp2) {
|
|
dxs = mid[4] - mid[0];
|
|
dys = mid[5] - mid[1];
|
|
if (dxs == 0f && dys == 0f) {
|
|
dxs = mid[6] - mid[0];
|
|
dys = mid[7] - mid[1];
|
|
}
|
|
}
|
|
if (p3eqp4) {
|
|
dxf = mid[6] - mid[2];
|
|
dyf = mid[7] - mid[3];
|
|
if (dxf == 0f && dyf == 0f) {
|
|
dxf = mid[6] - mid[0];
|
|
dyf = mid[7] - mid[1];
|
|
}
|
|
}
|
|
if (dxs == 0f && dys == 0f) {
|
|
// this happens if the "curve" is just a point
|
|
lineTo(mid[0], mid[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, offset0);
|
|
drawJoin(cdx, cdy, cx0, cy0, dxs, dys, cmx, cmy, offset0[0], offset0[1]);
|
|
|
|
int nSplits = findSubdivPoints(curve, mid, subdivTs, 8, lineWidth2);
|
|
|
|
final float[] l = lp;
|
|
final float[] r = rp;
|
|
|
|
int kind = 0;
|
|
BreakPtrIterator it = curve.breakPtsAtTs(mid, 8, subdivTs, nSplits);
|
|
while(it.hasNext()) {
|
|
int curCurveOff = it.next();
|
|
|
|
kind = computeOffsetCubic(mid, curCurveOff, 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.cmx = (l[kind - 2] - r[kind - 2]) / 2f;
|
|
this.cmy = (l[kind - 1] - r[kind - 1]) / 2f;
|
|
this.cdx = dxf;
|
|
this.cdy = dyf;
|
|
this.cx0 = xf;
|
|
this.cy0 = yf;
|
|
this.prev = DRAWING_OP_TO;
|
|
}
|
|
|
|
@Override public void quadTo(float x1, float y1, float x2, float y2) {
|
|
final float[] mid = middle;
|
|
|
|
mid[0] = cx0; mid[1] = cy0;
|
|
mid[2] = x1; mid[3] = y1;
|
|
mid[4] = x2; mid[5] = y2;
|
|
|
|
// 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 = mid[4], yf = mid[5];
|
|
float dxs = mid[2] - mid[0];
|
|
float dys = mid[3] - mid[1];
|
|
float dxf = mid[4] - mid[2];
|
|
float dyf = mid[5] - mid[3];
|
|
if ((dxs == 0f && dys == 0f) || (dxf == 0f && dyf == 0f)) {
|
|
dxs = dxf = mid[4] - mid[0];
|
|
dys = dyf = mid[5] - mid[1];
|
|
}
|
|
if (dxs == 0f && dys == 0f) {
|
|
// this happens if the "curve" is just a point
|
|
lineTo(mid[0], mid[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, offset0);
|
|
drawJoin(cdx, cdy, cx0, cy0, dxs, dys, cmx, cmy, offset0[0], offset0[1]);
|
|
|
|
int nSplits = findSubdivPoints(curve, mid, subdivTs, 6, lineWidth2);
|
|
|
|
final float[] l = lp;
|
|
final float[] r = rp;
|
|
|
|
int kind = 0;
|
|
BreakPtrIterator it = curve.breakPtsAtTs(mid, 6, subdivTs, nSplits);
|
|
while(it.hasNext()) {
|
|
int curCurveOff = it.next();
|
|
|
|
kind = computeOffsetQuad(mid, curCurveOff, 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.cmx = (l[kind - 2] - r[kind - 2]) / 2f;
|
|
this.cmy = (l[kind - 1] - r[kind - 1]) / 2f;
|
|
this.cdx = dxf;
|
|
this.cdy = dyf;
|
|
this.cx0 = xf;
|
|
this.cy0 = yf;
|
|
this.prev = DRAWING_OP_TO;
|
|
}
|
|
|
|
@Override public long getNativeConsumer() {
|
|
throw new InternalError("Stroker doesn't use a native consumer");
|
|
}
|
|
|
|
// a stack of polynomial curves where each curve shares endpoints with
|
|
// adjacent ones.
|
|
static final class PolyStack {
|
|
private static final byte TYPE_LINETO = (byte) 0;
|
|
private static final byte TYPE_QUADTO = (byte) 1;
|
|
private static final byte TYPE_CUBICTO = (byte) 2;
|
|
|
|
float[] curves;
|
|
int end;
|
|
byte[] curveTypes;
|
|
int numCurves;
|
|
|
|
// per-thread renderer context
|
|
final RendererContext rdrCtx;
|
|
|
|
// per-thread initial arrays (large enough to satisfy most usages: 8192)
|
|
// +1 to avoid recycling in Helpers.widenArray()
|
|
private final float[] curves_initial = new float[INITIAL_LARGE_ARRAY + 1]; // 32K
|
|
private final byte[] curveTypes_initial = new byte[INITIAL_LARGE_ARRAY + 1]; // 8K
|
|
|
|
// used marks (stats only)
|
|
int curveTypesUseMark;
|
|
int curvesUseMark;
|
|
|
|
/**
|
|
* Constructor
|
|
* @param rdrCtx per-thread renderer context
|
|
*/
|
|
PolyStack(final RendererContext rdrCtx) {
|
|
this.rdrCtx = rdrCtx;
|
|
|
|
curves = curves_initial;
|
|
curveTypes = curveTypes_initial;
|
|
end = 0;
|
|
numCurves = 0;
|
|
|
|
if (doStats) {
|
|
curveTypesUseMark = 0;
|
|
curvesUseMark = 0;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Disposes this PolyStack:
|
|
* clean up before reusing this instance
|
|
*/
|
|
void dispose() {
|
|
end = 0;
|
|
numCurves = 0;
|
|
|
|
if (doStats) {
|
|
RendererContext.stats.stat_rdr_poly_stack_types
|
|
.add(curveTypesUseMark);
|
|
RendererContext.stats.stat_rdr_poly_stack_curves
|
|
.add(curvesUseMark);
|
|
// reset marks
|
|
curveTypesUseMark = 0;
|
|
curvesUseMark = 0;
|
|
}
|
|
|
|
// Return arrays:
|
|
// curves and curveTypes are kept dirty
|
|
if (curves != curves_initial) {
|
|
rdrCtx.putDirtyFloatArray(curves);
|
|
curves = curves_initial;
|
|
}
|
|
|
|
if (curveTypes != curveTypes_initial) {
|
|
rdrCtx.putDirtyByteArray(curveTypes);
|
|
curveTypes = curveTypes_initial;
|
|
}
|
|
}
|
|
|
|
private void ensureSpace(final int n) {
|
|
// use substraction to avoid integer overflow:
|
|
if (curves.length - end < n) {
|
|
if (doStats) {
|
|
RendererContext.stats.stat_array_stroker_polystack_curves
|
|
.add(end + n);
|
|
}
|
|
curves = rdrCtx.widenDirtyFloatArray(curves, end, end + n);
|
|
}
|
|
if (curveTypes.length <= numCurves) {
|
|
if (doStats) {
|
|
RendererContext.stats.stat_array_stroker_polystack_curveTypes
|
|
.add(numCurves + 1);
|
|
}
|
|
curveTypes = rdrCtx.widenDirtyByteArray(curveTypes,
|
|
numCurves,
|
|
numCurves + 1);
|
|
}
|
|
}
|
|
|
|
void pushCubic(float x0, float y0,
|
|
float x1, float y1,
|
|
float x2, float y2)
|
|
{
|
|
ensureSpace(6);
|
|
curveTypes[numCurves++] = TYPE_CUBICTO;
|
|
// we reverse the coordinate order to make popping easier
|
|
final float[] _curves = curves;
|
|
int e = end;
|
|
_curves[e++] = x2; _curves[e++] = y2;
|
|
_curves[e++] = x1; _curves[e++] = y1;
|
|
_curves[e++] = x0; _curves[e++] = y0;
|
|
end = e;
|
|
}
|
|
|
|
void pushQuad(float x0, float y0,
|
|
float x1, float y1)
|
|
{
|
|
ensureSpace(4);
|
|
curveTypes[numCurves++] = TYPE_QUADTO;
|
|
final float[] _curves = curves;
|
|
int e = end;
|
|
_curves[e++] = x1; _curves[e++] = y1;
|
|
_curves[e++] = x0; _curves[e++] = y0;
|
|
end = e;
|
|
}
|
|
|
|
void pushLine(float x, float y) {
|
|
ensureSpace(2);
|
|
curveTypes[numCurves++] = TYPE_LINETO;
|
|
curves[end++] = x; curves[end++] = y;
|
|
}
|
|
|
|
void popAll(PathConsumer2D io) {
|
|
if (doStats) {
|
|
// update used marks:
|
|
if (numCurves > curveTypesUseMark) {
|
|
curveTypesUseMark = numCurves;
|
|
}
|
|
if (end > curvesUseMark) {
|
|
curvesUseMark = end;
|
|
}
|
|
}
|
|
final byte[] _curveTypes = curveTypes;
|
|
final float[] _curves = curves;
|
|
int nc = numCurves;
|
|
int e = end;
|
|
|
|
while (nc != 0) {
|
|
switch(_curveTypes[--nc]) {
|
|
case TYPE_LINETO:
|
|
e -= 2;
|
|
io.lineTo(_curves[e], _curves[e+1]);
|
|
continue;
|
|
case TYPE_QUADTO:
|
|
e -= 4;
|
|
io.quadTo(_curves[e+0], _curves[e+1],
|
|
_curves[e+2], _curves[e+3]);
|
|
continue;
|
|
case TYPE_CUBICTO:
|
|
e -= 6;
|
|
io.curveTo(_curves[e+0], _curves[e+1],
|
|
_curves[e+2], _curves[e+3],
|
|
_curves[e+4], _curves[e+5]);
|
|
continue;
|
|
default:
|
|
}
|
|
}
|
|
numCurves = 0;
|
|
end = 0;
|
|
}
|
|
|
|
@Override
|
|
public String toString() {
|
|
String ret = "";
|
|
int nc = numCurves;
|
|
int e = end;
|
|
int len;
|
|
while (nc != 0) {
|
|
switch(curveTypes[--nc]) {
|
|
case TYPE_LINETO:
|
|
len = 2;
|
|
ret += "line: ";
|
|
break;
|
|
case TYPE_QUADTO:
|
|
len = 4;
|
|
ret += "quad: ";
|
|
break;
|
|
case TYPE_CUBICTO:
|
|
len = 6;
|
|
ret += "cubic: ";
|
|
break;
|
|
default:
|
|
len = 0;
|
|
}
|
|
e -= len;
|
|
ret += Arrays.toString(Arrays.copyOfRange(curves, e, e+len))
|
|
+ "\n";
|
|
}
|
|
return ret;
|
|
}
|
|
}
|
|
}
|