JDK14/Java14源码在线阅读
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package sun.java2d.marlin;
import java.util.Arrays;
import sun.java2d.marlin.DTransformingPathConsumer2D.CurveBasicMonotonizer;
import sun.java2d.marlin.DTransformingPathConsumer2D.CurveClipSplitter;
/**
* The <code>DDasher</code> class takes a series of linear commands
* (<code>moveTo</code>, <code>lineTo</code>, <code>close</code> and
* <code>end</code>) and breaks them into smaller segments according to a
* dash pattern array and a starting dash phase.
*
* <p> Issues: in J2Se, a zero length dash segment as drawn as a very
* short dash, whereas Pisces does not draw anything. The PostScript
* semantics are unclear.
*
*/
final class DDasher implements DPathConsumer2D, MarlinConst {
/* huge circle with radius ~ 2E9 only needs 12 subdivision levels */
static final int REC_LIMIT = 16;
static final double CURVE_LEN_ERR = MarlinProperties.getCurveLengthError(); // 0.01 initial
static final double MIN_T_INC = 1.0d / (1 << REC_LIMIT);
static final double EPS = 1e-6d;
// More than 24 bits of mantissa means we can no longer accurately
// measure the number of times cycled through the dash array so we
// punt and override the phase to just be 0 past that point.
static final double MAX_CYCLES = 16000000.0d;
private DPathConsumer2D out;
private double[] dash;
private int dashLen;
private double startPhase;
private boolean startDashOn;
private int startIdx;
private boolean starting;
private boolean needsMoveTo;
private int idx;
private boolean dashOn;
private double phase;
// The starting point of the path
private double sx0, sy0;
// the current point
private double cx0, cy0;
// temporary storage for the current curve
private final double[] curCurvepts;
// per-thread renderer context
final DRendererContext rdrCtx;
// flag to recycle dash array copy
boolean recycleDashes;
// We don't emit the first dash right away. If we did, caps would be
// drawn on it, but we need joins to be drawn if there's a closePath()
// So, we store the path elements that make up the first dash in the
// buffer below.
private double[] firstSegmentsBuffer; // dynamic array
private int firstSegidx;
// dashes ref (dirty)
final DoubleArrayCache.Reference dashes_ref;
// firstSegmentsBuffer ref (dirty)
final DoubleArrayCache.Reference firstSegmentsBuffer_ref;
// Bounds of the drawing region, at pixel precision.
private double[] clipRect;
// the outcode of the current point
private int cOutCode = 0;
private boolean subdivide = DO_CLIP_SUBDIVIDER;
private final LengthIterator li = new LengthIterator();
private final CurveClipSplitter curveSplitter;
private double cycleLen;
private boolean outside;
private double totalSkipLen;
/**
* Constructs a <code>DDasher</code>.
* @param rdrCtx per-thread renderer context
*/
DDasher(final DRendererContext rdrCtx) {
this.rdrCtx = rdrCtx;
dashes_ref = rdrCtx.newDirtyDoubleArrayRef(INITIAL_ARRAY); // 1K
firstSegmentsBuffer_ref = rdrCtx.newDirtyDoubleArrayRef(INITIAL_ARRAY); // 1K
firstSegmentsBuffer = firstSegmentsBuffer_ref.initial;
// we need curCurvepts to be able to contain 2 curves because when
// dashing curves, we need to subdivide it
curCurvepts = new double[8 * 2];
this.curveSplitter = rdrCtx.curveClipSplitter;
}
/**
* Initialize the <code>DDasher</code>.
*
* @param out an output <code>DPathConsumer2D</code>.
* @param dash an array of <code>double</code>s containing the dash pattern
* @param dashLen length of the given dash array
* @param phase a <code>double</code> containing the dash phase
* @param recycleDashes true to indicate to recycle the given dash array
* @return this instance
*/
DDasher init(final DPathConsumer2D out, final double[] dash, final int dashLen,
double phase, final boolean recycleDashes)
{
this.out = out;
// Normalize so 0 <= phase < dash[0]
int sidx = 0;
dashOn = true;
// note: BasicStroke constructor checks dash elements and sum > 0
double sum = 0.0d;
for (int i = 0; i < dashLen; i++) {
sum += dash[i];
}
this.cycleLen = sum;
double cycles = phase / sum;
if (phase < 0.0d) {
if (-cycles >= MAX_CYCLES) {
phase = 0.0d;
} else {
int fullcycles = FloatMath.floor_int(-cycles);
if ((fullcycles & dashLen & 1) != 0) {
dashOn = !dashOn;
}
phase += fullcycles * sum;
while (phase < 0.0d) {
if (--sidx < 0) {
sidx = dashLen - 1;
}
phase += dash[sidx];
dashOn = !dashOn;
}
}
} else if (phase > 0.0d) {
if (cycles >= MAX_CYCLES) {
phase = 0.0d;
} else {
int fullcycles = FloatMath.floor_int(cycles);
if ((fullcycles & dashLen & 1) != 0) {
dashOn = !dashOn;
}
phase -= fullcycles * sum;
double d;
while (phase >= (d = dash[sidx])) {
phase -= d;
sidx = (sidx + 1) % dashLen;
dashOn = !dashOn;
}
}
}
this.dash = dash;
this.dashLen = dashLen;
this.phase = phase;
this.startPhase = phase;
this.startDashOn = dashOn;
this.startIdx = sidx;
this.starting = true;
this.needsMoveTo = false;
this.firstSegidx = 0;
this.recycleDashes = recycleDashes;
if (rdrCtx.doClip) {
this.clipRect = rdrCtx.clipRect;
} else {
this.clipRect = null;
this.cOutCode = 0;
}
return this; // fluent API
}
/**
* Disposes this dasher:
* clean up before reusing this instance
*/
void dispose() {
if (DO_CLEAN_DIRTY) {
// Force zero-fill dirty arrays:
Arrays.fill(curCurvepts, 0.0d);
}
// Return arrays:
if (recycleDashes) {
dash = dashes_ref.putArray(dash);
}
firstSegmentsBuffer = firstSegmentsBuffer_ref.putArray(firstSegmentsBuffer);
}
double[] copyDashArray(final float[] dashes) {
final int len = dashes.length;
final double[] newDashes;
if (len <= MarlinConst.INITIAL_ARRAY) {
newDashes = dashes_ref.initial;
} else {
if (DO_STATS) {
rdrCtx.stats.stat_array_dasher_dasher.add(len);
}
newDashes = dashes_ref.getArray(len);
}
for (int i = 0; i < len; i++) { newDashes[i] = dashes[i]; }
return newDashes;
}
@Override
public void moveTo(final double x0, final double y0) {
if (firstSegidx != 0) {
out.moveTo(sx0, sy0);
emitFirstSegments();
}
this.needsMoveTo = true;
this.idx = startIdx;
this.dashOn = this.startDashOn;
this.phase = this.startPhase;
this.cx0 = x0;
this.cy0 = y0;
// update starting point:
this.sx0 = x0;
this.sy0 = y0;
this.starting = true;
if (clipRect != null) {
final int outcode = DHelpers.outcode(x0, y0, clipRect);
this.cOutCode = outcode;
this.outside = false;
this.totalSkipLen = 0.0d;
}
}
private void emitSeg(double[] buf, int off, int type) {
switch (type) {
case 4:
out.lineTo(buf[off], buf[off + 1]);
return;
case 8:
out.curveTo(buf[off ], buf[off + 1],
buf[off + 2], buf[off + 3],
buf[off + 4], buf[off + 5]);
return;
case 6:
out.quadTo(buf[off ], buf[off + 1],
buf[off + 2], buf[off + 3]);
return;
default:
}
}
private void emitFirstSegments() {
final double[] fSegBuf = firstSegmentsBuffer;
for (int i = 0, len = firstSegidx; i < len; ) {
int type = (int)fSegBuf[i];
emitSeg(fSegBuf, i + 1, type);
i += (type - 1);
}
firstSegidx = 0;
}
// precondition: pts must be in relative coordinates (relative to x0,y0)
private void goTo(final double[] pts, final int off, final int type,
final boolean on)
{
final int index = off + type;
final double x = pts[index - 4];
final double y = pts[index - 3];
if (on) {
if (starting) {
goTo_starting(pts, off, type);
} else {
if (needsMoveTo) {
needsMoveTo = false;
out.moveTo(cx0, cy0);
}
emitSeg(pts, off, type);
}
} else {
if (starting) {
// low probability test (hotspot)
starting = false;
}
needsMoveTo = true;
}
this.cx0 = x;
this.cy0 = y;
}
private void goTo_starting(final double[] pts, final int off, final int type) {
int len = type - 1; // - 2 + 1
int segIdx = firstSegidx;
double[] buf = firstSegmentsBuffer;
if (segIdx + len > buf.length) {
if (DO_STATS) {
rdrCtx.stats.stat_array_dasher_firstSegmentsBuffer
.add(segIdx + len);
}
firstSegmentsBuffer = buf
= firstSegmentsBuffer_ref.widenArray(buf, segIdx,
segIdx + len);
}
buf[segIdx++] = type;
len--;
// small arraycopy (2, 4 or 6) but with offset:
System.arraycopy(pts, off, buf, segIdx, len);
firstSegidx = segIdx + len;
}
@Override
public void lineTo(final double x1, final double y1) {
final int outcode0 = this.cOutCode;
if (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) {
// overlap 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;
skipLineTo(x1, y1);
return;
}
}
this.cOutCode = outcode1;
if (this.outside) {
this.outside = false;
// Adjust current index, phase & dash:
skipLen();
}
}
_lineTo(x1, y1);
}
private void _lineTo(final double x1, final double y1) {
final double dx = x1 - cx0;
final double dy = y1 - cy0;
double len = dx * dx + dy * dy;
if (len == 0.0d) {
return;
}
len = Math.sqrt(len);
// The scaling factors needed to get the dx and dy of the
// transformed dash segments.
final double cx = dx / len;
final double cy = dy / len;
final double[] _curCurvepts = curCurvepts;
final double[] _dash = dash;
final int _dashLen = this.dashLen;
int _idx = idx;
boolean _dashOn = dashOn;
double _phase = phase;
double leftInThisDashSegment, rem;
while (true) {
leftInThisDashSegment = _dash[_idx] - _phase;
rem = len - leftInThisDashSegment;
if (rem <= EPS) {
_curCurvepts[0] = x1;
_curCurvepts[1] = y1;
goTo(_curCurvepts, 0, 4, _dashOn);
// Advance phase within current dash segment
_phase += len;
// compare values using epsilon:
if (Math.abs(rem) <= EPS) {
_phase = 0.0d;
_idx = (_idx + 1) % _dashLen;
_dashOn = !_dashOn;
}
break;
}
_curCurvepts[0] = cx0 + leftInThisDashSegment * cx;
_curCurvepts[1] = cy0 + leftInThisDashSegment * cy;
goTo(_curCurvepts, 0, 4, _dashOn);
len = rem;
// Advance to next dash segment
_idx = (_idx + 1) % _dashLen;
_dashOn = !_dashOn;
_phase = 0.0d;
}
// Save local state:
idx = _idx;
dashOn = _dashOn;
phase = _phase;
}
private void skipLineTo(final double x1, final double y1) {
final double dx = x1 - cx0;
final double dy = y1 - cy0;
double len = dx * dx + dy * dy;
if (len != 0.0d) {
len = Math.sqrt(len);
}
// Accumulate skipped length:
this.outside = true;
this.totalSkipLen += len;
// Fix initial move:
this.needsMoveTo = true;
this.starting = false;
this.cx0 = x1;
this.cy0 = y1;
}
public void skipLen() {
double len = this.totalSkipLen;
this.totalSkipLen = 0.0d;
final double[] _dash = dash;
final int _dashLen = this.dashLen;
int _idx = idx;
boolean _dashOn = dashOn;
double _phase = phase;
// -2 to ensure having 2 iterations of the post-loop
// to compensate the remaining phase
final long fullcycles = (long)Math.floor(len / cycleLen) - 2L;
if (fullcycles > 0L) {
len -= cycleLen * fullcycles;
final long iterations = fullcycles * _dashLen;
_idx = (int) (iterations + _idx) % _dashLen;
_dashOn = (iterations + (_dashOn ? 1L : 0L) & 1L) == 1L;
}
double leftInThisDashSegment, rem;
while (true) {
leftInThisDashSegment = _dash[_idx] - _phase;
rem = len - leftInThisDashSegment;
if (rem <= EPS) {
// Advance phase within current dash segment
_phase += len;
// compare values using epsilon:
if (Math.abs(rem) <= EPS) {
_phase = 0.0d;
_idx = (_idx + 1) % _dashLen;
_dashOn = !_dashOn;
}
break;
}
len = rem;
// Advance to next dash segment
_idx = (_idx + 1) % _dashLen;
_dashOn = !_dashOn;
_phase = 0.0d;
}
// Save local state:
idx = _idx;
dashOn = _dashOn;
phase = _phase;
}
// preconditions: curCurvepts must be an array of length at least 2 * type,
// that contains the curve we want to dash in the first type elements
private void somethingTo(final int type) {
final double[] _curCurvepts = curCurvepts;
if (pointCurve(_curCurvepts, type)) {
return;
}
final LengthIterator _li = li;
final double[] _dash = dash;
final int _dashLen = this.dashLen;
_li.initializeIterationOnCurve(_curCurvepts, type);
int _idx = idx;
boolean _dashOn = dashOn;
double _phase = phase;
// initially the current curve is at curCurvepts[0...type]
int curCurveoff = 0;
double prevT = 0.0d;
double t;
double leftInThisDashSegment = _dash[_idx] - _phase;
while ((t = _li.next(leftInThisDashSegment)) < 1.0d) {
if (t != 0.0d) {
DHelpers.subdivideAt((t - prevT) / (1.0d - prevT),
_curCurvepts, curCurveoff,
_curCurvepts, 0, type);
prevT = t;
goTo(_curCurvepts, 2, type, _dashOn);
curCurveoff = type;
}
// Advance to next dash segment
_idx = (_idx + 1) % _dashLen;
_dashOn = !_dashOn;
_phase = 0.0d;
leftInThisDashSegment = _dash[_idx];
}
goTo(_curCurvepts, curCurveoff + 2, type, _dashOn);
_phase += _li.lastSegLen();
// compare values using epsilon:
if (_phase + EPS >= _dash[_idx]) {
_phase = 0.0d;
_idx = (_idx + 1) % _dashLen;
_dashOn = !_dashOn;
}
// Save local state:
idx = _idx;
dashOn = _dashOn;
phase = _phase;
// reset LengthIterator:
_li.reset();
}
private void skipSomethingTo(final int type) {
final double[] _curCurvepts = curCurvepts;
if (pointCurve(_curCurvepts, type)) {
return;
}
final LengthIterator _li = li;
_li.initializeIterationOnCurve(_curCurvepts, type);
// In contrary to somethingTo(),
// just estimate properly the curve length:
final double len = _li.totalLength();
// Accumulate skipped length:
this.outside = true;
this.totalSkipLen += len;
// Fix initial move:
this.needsMoveTo = true;
this.starting = false;
}
private static boolean pointCurve(final double[] curve, final int type) {
for (int i = 2; i < type; i++) {
if (curve[i] != curve[i-2]) {
return false;
}
}
return true;
}
// Objects of this class are used to iterate through curves. They return
// t values where the left side of the curve has a specified length.
// It does this by subdividing the input curve until a certain error
// condition has been met. A recursive subdivision procedure would
// return as many as 1<<limit curves, but this is an iterator and we
// don't need all the curves all at once, so what we carry out a
// lazy inorder traversal of the recursion tree (meaning we only move
// through the tree when we need the next subdivided curve). This saves
// us a lot of memory because at any one time we only need to store
// limit+1 curves - one for each level of the tree + 1.
// NOTE: the way we do things here is not enough to traverse a general
// tree; however, the trees we are interested in have the property that
// every non leaf node has exactly 2 children
static final class LengthIterator {
// Holds the curves at various levels of the recursion. The root
// (i.e. the original curve) is at recCurveStack[0] (but then it
// gets subdivided, the left half is put at 1, so most of the time
// only the right half of the original curve is at 0)
private final double[][] recCurveStack; // dirty
// sidesRight[i] indicates whether the node at level i+1 in the path from
// the root to the current leaf is a left or right child of its parent.
private final boolean[] sidesRight; // dirty
private int curveType;
// lastT and nextT delimit the current leaf.
private double nextT;
private double lenAtNextT;
private double lastT;
private double lenAtLastT;
private double lenAtLastSplit;
private double lastSegLen;
// the current level in the recursion tree. 0 is the root. limit
// is the deepest possible leaf.
private int recLevel;
private boolean done;
// the lengths of the lines of the control polygon. Only its first
// curveType/2 - 1 elements are valid. This is an optimization. See
// next() for more detail.
private final double[] curLeafCtrlPolyLengths = new double[3];
LengthIterator() {
this.recCurveStack = new double[REC_LIMIT + 1][8];
this.sidesRight = new boolean[REC_LIMIT];
// if any methods are called without first initializing this object
// on a curve, we want it to fail ASAP.
this.nextT = Double.MAX_VALUE;
this.lenAtNextT = Double.MAX_VALUE;
this.lenAtLastSplit = Double.MIN_VALUE;
this.recLevel = Integer.MIN_VALUE;
this.lastSegLen = Double.MAX_VALUE;
this.done = true;
}
/**
* Reset this LengthIterator.
*/
void reset() {
// keep data dirty
// as it appears not useful to reset data:
if (DO_CLEAN_DIRTY) {
final int recLimit = recCurveStack.length - 1;
for (int i = recLimit; i >= 0; i--) {
Arrays.fill(recCurveStack[i], 0.0d);
}
Arrays.fill(sidesRight, false);
Arrays.fill(curLeafCtrlPolyLengths, 0.0d);
Arrays.fill(nextRoots, 0.0d);
Arrays.fill(flatLeafCoefCache, 0.0d);
flatLeafCoefCache[2] = -1.0d;
}
}
void initializeIterationOnCurve(final double[] pts, final int type) {
// optimize arraycopy (8 values faster than 6 = type):
System.arraycopy(pts, 0, recCurveStack[0], 0, 8);
this.curveType = type;
this.recLevel = 0;
this.lastT = 0.0d;
this.lenAtLastT = 0.0d;
this.nextT = 0.0d;
this.lenAtNextT = 0.0d;
goLeft(); // initializes nextT and lenAtNextT properly
this.lenAtLastSplit = 0.0d;
if (recLevel > 0) {
this.sidesRight[0] = false;
this.done = false;
} else {
// the root of the tree is a leaf so we're done.
this.sidesRight[0] = true;
this.done = true;
}
this.lastSegLen = 0.0d;
}
// 0 == false, 1 == true, -1 == invalid cached value.
private int cachedHaveLowAcceleration = -1;
private boolean haveLowAcceleration(final double err) {
if (cachedHaveLowAcceleration == -1) {
final double len1 = curLeafCtrlPolyLengths[0];
final double len2 = curLeafCtrlPolyLengths[1];
// the test below is equivalent to !within(len1/len2, 1, err).
// It is using a multiplication instead of a division, so it
// should be a bit faster.
if (!DHelpers.within(len1, len2, err * len2)) {
cachedHaveLowAcceleration = 0;
return false;
}
if (curveType == 8) {
final double len3 = curLeafCtrlPolyLengths[2];
// if len1 is close to 2 and 2 is close to 3, that probably
// means 1 is close to 3 so the second part of this test might
// not be needed, but it doesn't hurt to include it.
final double errLen3 = err * len3;
if (!(DHelpers.within(len2, len3, errLen3) &&
DHelpers.within(len1, len3, errLen3))) {
cachedHaveLowAcceleration = 0;
return false;
}
}
cachedHaveLowAcceleration = 1;
return true;
}
return (cachedHaveLowAcceleration == 1);
}
// we want to avoid allocations/gc so we keep this array so we
// can put roots in it,
private final double[] nextRoots = new double[4];
// caches the coefficients of the current leaf in its flattened
// form (see inside next() for what that means). The cache is
// invalid when it's third element is negative, since in any
// valid flattened curve, this would be >= 0.
private final double[] flatLeafCoefCache = new double[]{0.0d, 0.0d, -1.0d, 0.0d};
// returns the t value where the remaining curve should be split in
// order for the left subdivided curve to have length len. If len
// is >= than the length of the uniterated curve, it returns 1.
double next(final double len) {
final double targetLength = lenAtLastSplit + len;
while (lenAtNextT < targetLength) {
if (done) {
lastSegLen = lenAtNextT - lenAtLastSplit;
return 1.0d;
}
goToNextLeaf();
}
lenAtLastSplit = targetLength;
final double leaflen = lenAtNextT - lenAtLastT;
double t = (targetLength - lenAtLastT) / leaflen;
// cubicRootsInAB is a fairly expensive call, so we just don't do it
// if the acceleration in this section of the curve is small enough.
if (!haveLowAcceleration(0.05d)) {
// We flatten the current leaf along the x axis, so that we're
// left with a, b, c which define a 1D Bezier curve. We then
// solve this to get the parameter of the original leaf that
// gives us the desired length.
final double[] _flatLeafCoefCache = flatLeafCoefCache;
if (_flatLeafCoefCache[2] < 0.0d) {
double x = curLeafCtrlPolyLengths[0],
y = x + curLeafCtrlPolyLengths[1];
if (curveType == 8) {
double z = y + curLeafCtrlPolyLengths[2];
_flatLeafCoefCache[0] = 3.0d * (x - y) + z;
_flatLeafCoefCache[1] = 3.0d * (y - 2.0d * x);
_flatLeafCoefCache[2] = 3.0d * x;
_flatLeafCoefCache[3] = -z;
} else if (curveType == 6) {
_flatLeafCoefCache[0] = 0.0d;
_flatLeafCoefCache[1] = y - 2.0d * x;
_flatLeafCoefCache[2] = 2.0d * x;
_flatLeafCoefCache[3] = -y;
}
}
double a = _flatLeafCoefCache[0];
double b = _flatLeafCoefCache[1];
double c = _flatLeafCoefCache[2];
double d = t * _flatLeafCoefCache[3];
// we use cubicRootsInAB here, because we want only roots in 0, 1,
// and our quadratic root finder doesn't filter, so it's just a
// matter of convenience.
final int n = DHelpers.cubicRootsInAB(a, b, c, d, nextRoots, 0, 0.0d, 1.0d);
if (n == 1 && !Double.isNaN(nextRoots[0])) {
t = nextRoots[0];
}
}
// t is relative to the current leaf, so we must make it a valid parameter
// of the original curve.
t = t * (nextT - lastT) + lastT;
if (t >= 1.0d) {
t = 1.0d;
done = true;
}
// even if done = true, if we're here, that means targetLength
// is equal to, or very, very close to the total length of the
// curve, so lastSegLen won't be too high. In cases where len
// overshoots the curve, this method will exit in the while
// loop, and lastSegLen will still be set to the right value.
lastSegLen = len;
return t;
}
double totalLength() {
while (!done) {
goToNextLeaf();
}
// reset LengthIterator:
reset();
return lenAtNextT;
}
double lastSegLen() {
return lastSegLen;
}
// go to the next leaf (in an inorder traversal) in the recursion tree
// preconditions: must be on a leaf, and that leaf must not be the root.
private void goToNextLeaf() {
// We must go to the first ancestor node that has an unvisited
// right child.
final boolean[] _sides = sidesRight;
int _recLevel = recLevel;
_recLevel--;
while(_sides[_recLevel]) {
if (_recLevel == 0) {
recLevel = 0;
done = true;
return;
}
_recLevel--;
}
_sides[_recLevel] = true;
// optimize arraycopy (8 values faster than 6 = type):
System.arraycopy(recCurveStack[_recLevel++], 0,
recCurveStack[_recLevel], 0, 8);
recLevel = _recLevel;
goLeft();
}
// go to the leftmost node from the current node. Return its length.
private void goLeft() {
final double len = onLeaf();
if (len >= 0.0d) {
lastT = nextT;
lenAtLastT = lenAtNextT;
nextT += (1 << (REC_LIMIT - recLevel)) * MIN_T_INC;
lenAtNextT += len;
// invalidate caches
flatLeafCoefCache[2] = -1.0d;
cachedHaveLowAcceleration = -1;
} else {
DHelpers.subdivide(recCurveStack[recLevel],
recCurveStack[recLevel + 1],
recCurveStack[recLevel], curveType);
sidesRight[recLevel] = false;
recLevel++;
goLeft();
}
}
// this is a bit of a hack. It returns -1 if we're not on a leaf, and
// the length of the leaf if we are on a leaf.
private double onLeaf() {
final double[] curve = recCurveStack[recLevel];
final int _curveType = curveType;
double polyLen = 0.0d;
double x0 = curve[0], y0 = curve[1];
for (int i = 2; i < _curveType; i += 2) {
final double x1 = curve[i], y1 = curve[i + 1];
final double len = DHelpers.linelen(x0, y0, x1, y1);
polyLen += len;
curLeafCtrlPolyLengths[(i >> 1) - 1] = len;
x0 = x1;
y0 = y1;
}
final double lineLen = DHelpers.linelen(curve[0], curve[1], x0, y0);
if ((polyLen - lineLen) < CURVE_LEN_ERR || recLevel == REC_LIMIT) {
return (polyLen + lineLen) / 2.0d;
}
return -1.0d;
}
}
@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) {
// overlap 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;
skipCurveTo(x1, y1, x2, y2, x3, y3);
return;
}
}
this.cOutCode = outcode3;
if (this.outside) {
this.outside = false;
// Adjust current index, phase & dash:
skipLen();
}
}
_curveTo(x1, y1, x2, y2, x3, y3);
}
private void _curveTo(final double x1, final double y1,
final double x2, final double y2,
final double x3, final double y3)
{
final double[] _curCurvepts = curCurvepts;
// monotonize curve:
final CurveBasicMonotonizer monotonizer
= rdrCtx.monotonizer.curve(cx0, cy0, x1, y1, x2, y2, x3, y3);
final int nSplits = monotonizer.nbSplits;
final double[] mid = monotonizer.middle;
for (int i = 0, off = 0; i <= nSplits; i++, off += 6) {
// optimize arraycopy (8 values faster than 6 = type):
System.arraycopy(mid, off, _curCurvepts, 0, 8);
somethingTo(8);
}
}
private void skipCurveTo(final double x1, final double y1,
final double x2, final double y2,
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