shape ops work in progress
git-svn-id: http://skia.googlecode.com/svn/trunk@3861 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/experimental/Intersection/Simplify.cpp b/experimental/Intersection/Simplify.cpp
index 2ecc9b2..83af104 100644
--- a/experimental/Intersection/Simplify.cpp
+++ b/experimental/Intersection/Simplify.cpp
@@ -18,6 +18,15 @@
#undef SkASSERT
#define SkASSERT(cond) while (!(cond)) { sk_throw(); }
+// Terminology:
+// A Path contains one of more Contours
+// A Contour is made up of Segment array
+// A Segment is described by a Verb and a Point array
+// A Verb is one of Line, Quad(ratic), and Cubic
+// A Segment contains a Span array
+// A Span is describes a portion of a Segment using starting and ending T
+// T values range from 0 to 1, where 0 is the first Point in the Segment
+
// FIXME: remove once debugging is complete
#if 0 // set to 1 for no debugging whatsoever
@@ -276,7 +285,7 @@
}
}
-static SkPath::Verb QuadReduceOrder(const SkPoint a[4],
+static SkPath::Verb QuadReduceOrder(const SkPoint a[3],
SkTDArray<SkPoint>& reducePts) {
const Quadratic aQuad = {{a[0].fX, a[0].fY}, {a[1].fX, a[1].fY},
{a[2].fX, a[2].fY}};
@@ -304,6 +313,18 @@
return (SkPath::Verb) (order - 1);
}
+static bool QuadIsLinear(const SkPoint a[3]) {
+ const Quadratic aQuad = {{a[0].fX, a[0].fY}, {a[1].fX, a[1].fY},
+ {a[2].fX, a[2].fY}};
+ return isLinear(aQuad, 0, 2);
+}
+
+static bool CubicIsLinear(const SkPoint a[4]) {
+ const Cubic aCubic = {{a[0].fX, a[0].fY}, {a[1].fX, a[1].fY},
+ {a[2].fX, a[2].fY}, {a[3].fX, a[3].fY}};
+ return isLinear(aCubic, 0, 3);
+}
+
static SkScalar LineLeftMost(const SkPoint a[2], double startT, double endT) {
const _Line aLine = {{a[0].fX, a[0].fY}, {a[1].fX, a[1].fY}};
double x[2];
@@ -338,6 +359,57 @@
return implicit_matches_ulps(aLine, bLine, 32);
}
+// sorting angles
+// given angles of {dx dy ddx ddy dddx dddy} sort them
+class Angle {
+public:
+ bool operator<(const Angle& rh) const {
+ if ((dy < 0) ^ (rh.dy < 0)) {
+ return dy < 0;
+ }
+ SkScalar cmp = dx * rh.dy - rh.dx * dy;
+ if (cmp) {
+ return cmp < 0;
+ }
+ if ((ddy < 0) ^ (rh.ddy < 0)) {
+ return ddy < 0;
+ }
+ cmp = ddx * rh.ddy - rh.ddx * ddy;
+ if (cmp) {
+ return cmp < 0;
+ }
+ if ((dddy < 0) ^ (rh.dddy < 0)) {
+ return ddy < 0;
+ }
+ return dddx * rh.dddy < rh.dddx * dddy;
+ }
+
+ void set(SkPoint* pts, SkPath::Verb verb) {
+ dx = pts[1].fX - pts[0].fX; // b - a
+ dy = pts[1].fY - pts[0].fY;
+ if (verb == SkPath::kLine_Verb) {
+ ddx = ddy = dddx = dddy = 0;
+ return;
+ }
+ ddx = pts[2].fX - pts[1].fX - dx; // a - 2b + c
+ ddy = pts[2].fY - pts[2].fY - dy;
+ if (verb == SkPath::kQuad_Verb) {
+ dddx = dddy = 0;
+ return;
+ }
+ dddx = pts[3].fX + 3 * (pts[1].fX - pts[2].fX) - pts[0].fX;
+ dddy = pts[3].fY + 3 * (pts[1].fY - pts[2].fY) - pts[0].fY;
+ }
+
+private:
+ SkScalar dx;
+ SkScalar dy;
+ SkScalar ddx;
+ SkScalar ddy;
+ SkScalar dddx;
+ SkScalar dddy;
+};
+
// Bounds, unlike Rect, does not consider a vertical line to be empty.
struct Bounds : public SkRect {
static bool Intersects(const Bounds& a, const Bounds& b) {
@@ -371,12 +443,15 @@
class Segment;
-struct TEntry {
+struct Span {
double fT;
Segment* fOther;
double fOtherT;
- int fWinding;
- bool fDone; // set true when t to t+1 is processed
+ int fWinding; // accumulated from contours surrounding this one
+ // OPTIMIZATION: done needs only 2 bits (values are -1, 0, 1)
+ int fDone; // set when t to t+fDone is processed
+ // OPTIMIZATION: done needs only 2 bits (values are -1, 0, 1)
+ int fCoincident; // -1 start of coincidence, 0 no coincidence, 1 end
};
class Segment {
@@ -386,35 +461,10 @@
fID = ++gSegmentID;
#endif
}
-
- int addT(double newT, Segment& other) {
- // FIXME: in the pathological case where there is a ton of intercepts,
- // binary search?
- int insertedAt = -1;
- TEntry* entry;
- size_t tCount = fTs.count();
- double delta;
- for (size_t idx2 = 0; idx2 < tCount; ++idx2) {
- // OPTIMIZATION: if there are three or more identical Ts, then
- // the fourth and following could be further insertion-sorted so
- // that all the edges are clockwise or counterclockwise.
- // This could later limit segment tests to the two adjacent
- // neighbors, although it doesn't help with determining which
- // circular direction to go in.
- if (newT <= fTs[idx2].fT) {
- insertedAt = idx2;
- entry = fTs.insert(idx2);
- goto finish;
- }
- }
- insertedAt = tCount;
- entry = fTs.append();
-finish:
- entry->fT = newT;
- entry->fOther = &other;
- entry->fWinding = 1;
- entry->fDone = false;
- return insertedAt;
+
+ void addAngle(SkTDArray<Angle>& angles, double start, double end) {
+ // FIXME complete this
+ // start here;
}
bool addCubic(const SkPoint pts[4]) {
@@ -440,90 +490,298 @@
fBounds.setQuadBounds(pts);
}
+ int addT(double newT, Segment& other, int coincident) {
+ // FIXME: in the pathological case where there is a ton of intercepts,
+ // binary search?
+ int insertedAt = -1;
+ Span* span;
+ size_t tCount = fTs.count();
+ double delta;
+ for (size_t idx2 = 0; idx2 < tCount; ++idx2) {
+ // OPTIMIZATION: if there are three or more identical Ts, then
+ // the fourth and following could be further insertion-sorted so
+ // that all the edges are clockwise or counterclockwise.
+ // This could later limit segment tests to the two adjacent
+ // neighbors, although it doesn't help with determining which
+ // circular direction to go in.
+ if (newT <= fTs[idx2].fT) {
+ insertedAt = idx2;
+ span = fTs.insert(idx2);
+ goto finish;
+ }
+ }
+ insertedAt = tCount;
+ span = fTs.append();
+finish:
+ span->fT = newT;
+ span->fOther = &other;
+ span->fWinding = 1;
+ span->fDone = 0;
+ span->fCoincident = coincident;
+ fCoincident |= coincident;
+ return insertedAt;
+ }
+
const Bounds& bounds() const {
return fBounds;
}
- int coincidentCount() const {
- return fCoincidentCount;
+ bool done() const {
+ return fDone;
}
- int coincidentT(double newT, Segment& other, bool combo) {
- int index = addT(newT, other);
- if (combo) {
- fTs[index].fWinding = 2;
- } else {
- fTs[index].fWinding = 0;
- fTs[index].fDone = true;
+ int findCoincidentEnd(int start) const {
+ int tCount = fTs.count();
+ SkASSERT(start < tCount);
+ const Span& span = fTs[start];
+ SkASSERT(span.fCoincident);
+ for (int index = start + 1; index < tCount; ++index) {
+ const Span& match = fTs[index];
+ if (match.fOther == span.fOther) {
+ SkASSERT(match.fCoincident);
+ return index;
+ }
}
- ++fCoincidentCount;
- return index;
+ SkASSERT(0); // should never get here
+ return -1;
+ }
+
+ // start is the index of the beginning T of this edge
+ // it is guaranteed to have an end which describes a non-zero length (?)
+ // winding -1 means ccw, 1 means cw
+ // step is in/out -1 or 1
+ // spanIndex is returned
+ Segment* findNext(int start, int winding, int& step, int& spanIndex) {
+ SkASSERT(step == 1 || step == -1);
+ int count = fTs.count();
+ SkASSERT(step > 0 ? start < count - 1 : start > 0);
+ Span* startSpan = &fTs[start];
+ // FIXME:
+ // since Ts can be stepped either way, done markers must be careful
+ // not to assume that segment was only ascending in T. This shouldn't
+ // be a problem unless pathologically a segment can be partially
+ // ascending and partially descending -- maybe quads/cubic can do this?
+ startSpan->fDone = step;
+ SkPoint startLoc; // OPTIMIZATION: store this in the t span?
+ xyAtT(startSpan->fT, &startLoc);
+ SkPoint endLoc;
+ Span* endSpan;
+ int end = nextSpan(start, step, startLoc, startSpan, &endLoc, &endSpan);
+
+ // if we hit the end looking for span end, is that always an error?
+ SkASSERT(step > 0 ? end + 1 < count : end - 1 >= 0);
+
+ // preflight for coincidence -- if present, it may change winding
+ // considerations and whether reversed edges can be followed
+ bool foundCoincident = false;
+ int last = lastSpan(end, step, &startLoc, startSpan, foundCoincident);
+
+ // Discard opposing direction candidates if no coincidence was found.
+ int candidateCount = abs(last - end);
+ if (candidateCount == 1) {
+ SkASSERT(!foundCoincident);
+ // move in winding direction until edge in correct direction
+ // balance wrong direction edges before finding correct one
+ // this requres that the intersection is angularly sorted
+ // for a single intersection, special case -- choose the opposite
+ // edge that steps the same
+ Segment* other = endSpan->fOther;
+ SkASSERT(!other->fDone);
+ spanIndex = other->matchSpan(this, endSpan->fT);
+ SkASSERT(step < 0 ? spanIndex > 0 : spanIndex < other->fTs.count() - 1);
+ return other;
+ }
+
+ // find the next T that describes a length
+ SkTDArray<Angle> angles;
+ Segment* segmentCandidate = NULL;
+ int spanCandidate = -1;
+ int directionCandidate;
+ do {
+ endSpan = &fTs[end];
+ Segment* other = endSpan->fOther;
+ if (other->fDone) {
+ continue;
+ }
+ // if there is only one live crossing, and no coincidence, continue
+ // in the same direction
+ // if there is coincidence, the only choice may be to reverse direction
+ // find edge on either side of intersection
+ int oCount = other->fTs.count();
+ for (int oIndex = 0; oIndex < oCount; ++oIndex) {
+ Span& otherSpan = other->fTs[oIndex];
+ if (otherSpan.fOther != this) {
+ continue;
+ }
+ if (otherSpan.fOtherT != endSpan->fT) {
+ continue;
+ }
+ // if done == -1, prior span has already been processed
+ int next = other->nextSpan(oIndex, step, endLoc, &otherSpan,
+ NULL, NULL);
+ if (next < 0) {
+ continue;
+ }
+ bool otherIsCoincident;
+ last = other->lastSpan(next, step, &endLoc, &otherSpan,
+ otherIsCoincident);
+ if (step < 0) {
+
+ if (otherSpan.fDone >= 0 && oIndex > 0) {
+ // FIXME: this needs to loop on -- until t && pt are different
+ Span& prior = other->fTs[oIndex - 1];
+ if (prior.fDone > 0) {
+ continue;
+ }
+
+ }
+ } else { // step == 1
+ if (otherSpan.fDone <= 0 && oIndex < oCount - 1) {
+ // FIXME: this needs to loop on ++ until t && pt are different
+ Span& next = other->fTs[oIndex + 1];
+ if (next.fDone < 0) {
+ continue;
+ }
+ }
+ }
+ if (!segmentCandidate) {
+ segmentCandidate = other;
+ spanCandidate = oIndex;
+ directionCandidate = step;
+ continue;
+ }
+ // there's two or more matches
+ if (spanCandidate >= 0) { // retrieve first stored candidate
+ // add edge leading into junction
+ addAngle(angles, endSpan->fT, startSpan->fT);
+ // add edge leading away from junction
+ double nextT = nextSpan(end, step, endLoc, endSpan, NULL,
+ NULL);
+ if (nextT >= 0) {
+ addAngle(angles, endSpan->fT, nextT);
+ }
+ // add first stored candidate into junction
+ segmentCandidate->addAngle(angles,
+ segmentCandidate->fTs[spanCandidate - 1].fT,
+ segmentCandidate->fTs[spanCandidate].fT);
+ // add first stored candidate away from junction
+ segmentCandidate->addAngle(angles,
+ segmentCandidate->fTs[spanCandidate].fT,
+ segmentCandidate->fTs[spanCandidate + 1].fT);
+ }
+ // add candidate into and away from junction
+
+
+ // start here;
+ // more than once viable candidate -- need to
+ // measure angles to find best
+ // noncoincident quads/cubics may have the same initial angle
+ // as lines, so must sort by derivatives as well
+ // while we're here, figure out all connections given the
+ // initial winding info
+ // so the span needs to contain the pairing info found here
+ // this should include the winding computed for the edge, and
+ // what edge it connects to, and whether it is discarded
+ // (maybe discarded == abs(winding) > 1) ?
+ // only need derivatives for duration of sorting, add a new struct
+ // for pairings, remove extra spans that have zero length and
+ // reference an unused other
+ // for coincident, the last span on the other may be marked done
+ // (always?)
+ }
+ } while ((end += step) != last);
+ // if loop is exhausted, contour may be closed.
+ // FIXME: pass in close point so we can check for closure
+
+ // given a segment, and a sense of where 'inside' is, return the next
+ // segment. If this segment has an intersection, or ends in multiple
+ // segments, find the mate that continues the outside.
+ // note that if there are multiples, but no coincidence, we can limit
+ // choices to connections in the correct direction
+
+ // mark found segments as done
}
void findTooCloseToCall(int winding) {
- int limit = fTs.count() - 1;
- SkPoint matchPt;
+ int count = fTs.count();
+ if (count < 3) { // require t=0, x, 1 at minimum
+ return;
+ }
int matchIndex = 0;
- TEntry* match = &fTs[0];
- (*SegmentXYAtT[fVerb])(fPts, match->fT, &matchPt);
+ int moCount;
+ Span* match;
+ Segment* mOther;
+ do {
+ match = &fTs[matchIndex];
+ mOther = match->fOther;
+ moCount = mOther->fTs.count();
+ } while (moCount >= 3 || ++matchIndex < count - 1); // require t=0, x, 1 at minimum
+ SkPoint matchPt;
+ // OPTIMIZATION: defer matchPt until qualifying toCount is found?
+ xyAtT(match->fT, &matchPt);
// look for a pair of nearby T values that map to the same (x,y) value
// if found, see if the pair of other segments share a common point. If
// so, the span from here to there is coincident.
- for (int index = 1; index < limit; ++index) {
- TEntry* test = &fTs[index];
- if (test->fDone) {
+ for (int index = matchIndex + 1; index < count; ++index) {
+ Span* test = &fTs[index];
+ Segment* tOther = test->fOther;
+ int toCount = tOther->fTs.count();
+ if (toCount < 3) { // require t=0, x, 1 at minimum
continue;
}
SkPoint testPt;
- (*SegmentXYAtT[fVerb])(fPts, test->fT, &testPt);
+ xyAtT(test->fT, &testPt);
if (matchPt != testPt) {
matchIndex = index;
+ moCount = toCount;
+ match = test;
+ mOther = tOther;
matchPt = testPt;
continue;
}
- Segment* mOther = match->fOther;
- Segment* tOther = test->fOther;
- int moCount = mOther->fTs.count();
+ int moStart = -1; // FIXME: initialization is debugging only
for (int moIndex = 0; moIndex < moCount; ++moIndex) {
- TEntry& moEntry = mOther->fTs[moIndex];
- if (moEntry.fOther != tOther) {
+ Span& moSpan = mOther->fTs[moIndex];
+ if (moSpan.fOther == this) {
+ if (moSpan.fOtherT == match->fT) {
+ moStart = moIndex;
+ }
continue;
}
- int toIndex;
- int toCount = tOther->fTs.count();
+ if (moSpan.fOther != tOther) {
+ continue;
+ }
+ int toStart = -1;
+ int toIndex; // FIXME: initialization is debugging only
+ bool found = false;
for (toIndex = 0; toIndex < toCount; ++toIndex) {
- if (tOther->fTs[toIndex].fOther == mOther
- && tOther->fTs[toIndex].fOtherT
- == mOther->fTs[moIndex].fT) {
+ Span& toSpan = tOther->fTs[toIndex];
+ if (toSpan.fOther == this) {
+ if (toSpan.fOtherT == test->fT) {
+ toStart = toIndex;
+ }
+ continue;
+ }
+ if (toSpan.fOther == mOther && toSpan.fOtherT
+ == moSpan.fT) {
+ found = true;
break;
}
}
- bool sameDirection;
+ if (!found) {
+ continue;
+ }
+ SkASSERT(moStart >= 0);
+ SkASSERT(toStart >= 0);
// test to see if the segment between there and here is linear
- if (mOther->fVerb == SkPath::kLine_Verb
- && tOther->fVerb == SkPath::kLine_Verb) {
- sameDirection = mOther->fPts[0].fY != mOther->fPts[1].fY ?
- (mOther->fPts[0].fY < mOther->fPts[1].fY)
- ^ ((tOther->fPts[0].fY != tOther->fPts[1].fY)
- ? mOther->fPts[0].fY > mOther->fPts[1].fY
- : mOther->fPts[0].fX > mOther->fPts[1].fX)
- : (mOther->fPts[0].fX < mOther->fPts[1].fX)
- ^ (tOther->fPts[0].fY != tOther->fPts[1].fY
- ? tOther->fPts[0].fY > tOther->fPts[1].fY
- : tOther->fPts[0].fX > tOther->fPts[1].fX);
- goto isLinear;
+ if (!mOther->isLinear(moStart, moIndex)
+ || !tOther->isLinear(toStart, toIndex)) {
+ continue;
}
- // FIXME: determine if non-lines are essentially flat
-
- isLinear:
- if (sameDirection || winding == 1) { // FIXME: should check if y direction is same
- ++mOther->fTs[moIndex].fWinding;
- } else if (!--mOther->fTs[moIndex].fWinding) {
- mOther->fTs[moIndex].fDone = true;
- }
- if (!--tOther->fTs[toIndex].fWinding) {
- tOther->fTs[toIndex].fDone = true;
- }
+ mOther->fTs[moStart].fCoincident = -1;
+ tOther->fTs[toStart].fCoincident = -1;
+ mOther->fTs[moIndex].fCoincident = 1;
+ tOther->fTs[toIndex].fCoincident = 1;
}
nextStart:
;
@@ -534,8 +792,8 @@
// OPTIMIZATION: bsearch if count is honkin huge
int count = fTs.count();
for (int index = 0; index < count; ++index) {
- const TEntry& entry = fTs[index];
- if (t == entry.fT && match == entry.fOther) {
+ const Span& span = fTs[index];
+ if (t == span.fT && match == span.fOther) {
return index;
}
}
@@ -583,8 +841,8 @@
int count = fTs.count();
int index;
for (index = 1; index < count; ++index) {
- const TEntry& entry = fTs[index];
- double t = entry.fT;
+ const Span& span = fTs[index];
+ double t = span.fT;
SkScalar yIntercept = yAtT(t);
if (topY > yIntercept) {
topY = yIntercept;
@@ -635,6 +893,22 @@
bool intersected() const {
return fTs.count() > 0;
}
+
+ bool isLinear(int start, int end) const {
+ if (fVerb == SkPath::kLine_Verb) {
+ return true;
+ }
+ if (fVerb == SkPath::kQuad_Verb) {
+ SkPoint qPart[3];
+ QuadSubDivide(fPts, fTs[start].fT, fTs[end].fT, qPart);
+ return QuadIsLinear(qPart);
+ } else {
+ SkASSERT(fVerb == SkPath::kCubic_Verb);
+ SkPoint cPart[4];
+ CubicSubDivide(fPts, fTs[start].fT, fTs[end].fT, cPart);
+ return CubicIsLinear(cPart);
+ }
+ }
bool isHorizontal() const {
return fBounds.fTop == fBounds.fBottom;
@@ -644,10 +918,73 @@
return fBounds.fLeft == fBounds.fRight;
}
+ int lastSpan(int end, int step, const SkPoint* startLoc,
+ const Span* startSpan, bool& coincident) {
+ int last = end;
+ int count = fTs.count();
+ coincident = false;
+ SkPoint lastLoc;
+ do {
+ if (fTs[last].fCoincident == -step) {
+ coincident = true;
+ }
+ if (step > 0 ? ++last < count : --last >= 0) {
+ break;
+ }
+ Span* lastSpan = &fTs[last];
+ if (lastSpan->fT == startSpan->fT) {
+ continue;
+ }
+ xyAtT(lastSpan->fT, &lastLoc);
+ } while (*startLoc == lastLoc);
+ }
+
SkScalar leftMost(int start, int end) const {
return (*SegmentLeftMost[fVerb])(fPts, fTs[start].fT, fTs[end].fT);
}
+ int matchSpan(const Segment* match, double matchT)
+ {
+ int count = fTs.count();
+ for (int index = 0; index < count; ++index) {
+ Span& span = fTs[index];
+ if (span.fOther != match) {
+ continue;
+ }
+ if (span.fOtherT != matchT) {
+ continue;
+ }
+ return index;
+ }
+ SkASSERT(0); // should never get here
+ return -1;
+ }
+
+ int nextSpan(int from, int step, const SkPoint& fromLoc,
+ const Span* fromSpan, SkPoint* toLoc, Span** toSpan) {
+ int count = fTs.count();
+ int to = from;
+ while (step > 0 ? ++to < count : --to >= 0) {
+ Span* span = &fTs[to];
+ if (span->fT == fromSpan->fT) {
+ continue;
+ }
+ SkPoint loc;
+ xyAtT(span->fT, &loc);
+ if (fromLoc == loc) {
+ continue;
+ }
+ if (toLoc) {
+ *toLoc = loc;
+ }
+ if (toSpan) {
+ *toSpan = span;
+ }
+ return to;
+ }
+ return -1;
+ }
+
const SkPoint* pts() const {
return fPts;
}
@@ -655,33 +992,10 @@
void reset() {
fPts = NULL;
fVerb = (SkPath::Verb) -1;
- fCoincidentCount = 0;
fBounds.set(SK_ScalarMax, SK_ScalarMax, SK_ScalarMax, SK_ScalarMax);
fTs.reset();
- }
-
- void resolveCoincidence() {
- if (fCoincidentCount <= 2) {
- return;
- }
- SkASSERT(fVerb == SkPath::kLine_Verb);
- int tCount = fTs.count();
- for (int index = 0; index < tCount; ++index) {
- const TEntry& entry = fTs[index];
- if (entry.fWinding == 1) {
- continue;
- }
- for (int mIndex = index + 1; mIndex < tCount; ++mIndex) {
- const TEntry& match = fTs[mIndex];
- if (match.fT > entry.fT) {
- break;
- }
- if (match.fWinding == 1) {
- continue;
- }
-
- }
- }
+ fDone = false;
+ fCoincident = 0;
}
// OPTIMIZATION: remove this function if it's never called
@@ -718,11 +1032,9 @@
kLVerbStr[fVerb], i, fTs[i].fT, out.fX, out.fY,
fTs[i].fOther->fID, fTs[i].fOtherT, fTs[i].fWinding);
}
- SkDebugf("%*s [%d] fBounds=(l:%1.9g, t:%1.9g r:%1.9g, b:%1.9g)"
- " coincidentCount=%d\n",
+ SkDebugf("%*s [%d] fBounds=(l:%1.9g, t:%1.9g r:%1.9g, b:%1.9g)",
tab + sizeof(className), className, fID,
- fBounds.fLeft, fBounds.fTop, fBounds.fRight, fBounds.fBottom,
- fCoincidentCount);
+ fBounds.fLeft, fBounds.fTop, fBounds.fRight, fBounds.fBottom);
}
#endif
@@ -730,8 +1042,10 @@
const SkPoint* fPts;
SkPath::Verb fVerb;
Bounds fBounds;
- SkTDArray<TEntry> fTs; // two or more (always includes t=0 t=1)
- int fCoincidentCount;
+ SkTDArray<Span> fTs; // two or more (always includes t=0 t=1)
+ // FIXME: coincident only needs two bits (-1, 0, 1)
+ int fCoincident; // non-zero if some coincident span inside
+ bool fDone;
#if DEBUG_DUMP
int fID;
#endif
@@ -770,10 +1084,6 @@
return fBounds;
}
- void checkMultiple() {
- fCheckMultiple = true;
- }
-
void complete() {
setBounds();
fContainsIntercepts = false;
@@ -793,21 +1103,43 @@
void reset() {
fSegments.reset();
fBounds.set(SK_ScalarMax, SK_ScalarMax, SK_ScalarMax, SK_ScalarMax);
- fCheckMultiple = fContainsCurves = fContainsIntercepts = false;
+ fContainsCurves = fContainsIntercepts = false;
}
-
- void resolveCoincidence() {
- if (!fCheckMultiple) {
- return;
+
+ // OPTIMIZATION: feel pretty uneasy about this. It seems like once again
+ // we need to sort and walk edges in y, but that on the surface opens the
+ // same can of worms as before. But then, this is a rough sort based on
+ // segments' top, and not a true sort, so it could be ameniable to regular
+ // sorting instead of linear searching. Still feel like I'm missing something
+ Segment* topSegment() {
+ int segmentCount = fSegments.count();
+ SkASSERT(segmentCount > 0);
+ int best = -1;
+ Segment* bestSegment = NULL;
+ while (++best < segmentCount) {
+ Segment* testSegment = &fSegments[best];
+ if (testSegment->done()) {
+ continue;
+ }
+ bestSegment = testSegment;
+ break;
}
- int count = fSegments.count();
- for (int index = 0; index < count; ++index) {
- fSegments[index].resolveCoincidence();
+ if (!bestSegment) {
+ return NULL;
}
- }
-
- Segment& topSegment() {
- return fSegments[fTopSegment];
+ SkScalar bestTop = bestSegment->bounds().fTop;
+ for (int test = best + 1; test < segmentCount; ++test) {
+ Segment* testSegment = &fSegments[test];
+ if (testSegment->done()) {
+ continue;
+ }
+ SkScalar testTop = testSegment->bounds().fTop;
+ if (bestTop > testTop) {
+ bestTop = testTop;
+ bestSegment = testSegment;
+ }
+ }
+ return bestSegment;
}
#if DEBUG_DUMP
@@ -825,10 +1157,6 @@
tab + sizeof(className), className,
fBounds.fLeft, fBounds.fTop,
fBounds.fRight, fBounds.fBottom);
- SkDebugf("%*s.fTopSegment=%d\n", tab + sizeof(className), className,
- fTopSegment);
- SkDebugf("%*s.fCheckMultiple=%d\n", tab + sizeof(className),
- className, fCheckMultiple);
SkDebugf("%*s.fContainsIntercepts=%d\n", tab + sizeof(className),
className, fContainsIntercepts);
SkDebugf("%*s.fContainsCurves=%d\n", tab + sizeof(className),
@@ -845,15 +1173,9 @@
// FIXME: delete empty contour?
return;
}
- fTopSegment = 0;
fBounds = fSegments.front().bounds();
- SkScalar top = fBounds.fTop;
for (int index = 1; index < count; ++index) {
fBounds.growToInclude(fSegments[index].bounds());
- if (top > fBounds.fTop) {
- fTopSegment = index;
- top = fBounds.fTop;
- }
}
}
@@ -862,8 +1184,6 @@
private:
Bounds fBounds;
- int fTopSegment;
- bool fCheckMultiple; // more than 2 lines are coincident; resolve later
bool fContainsIntercepts;
bool fContainsCurves;
#if DEBUG_DUMP
@@ -988,11 +1308,6 @@
class Work {
public:
- enum CoincidentType {
- kEmpty,
- kCombo
- };
-
enum SegmentType {
kHorizontalLine_Segment = -1,
kVerticalLine_Segment = 0,
@@ -1010,11 +1325,10 @@
// be nearly equal, any problems caused by this should be taken care
// of later.
// On the edge or out of range values are negative; add 2 to get end
- int addT(double newT, const Work& other) {
+ int addT(double newT, const Work& other, int coincident) {
fContour->containsIntercepts();
- int index = fContour->fSegments[fIndex].addT(newT,
- other.fContour->fSegments[other.fIndex]);
- return index;
+ return fContour->fSegments[fIndex].addT(newT,
+ other.fContour->fSegments[other.fIndex], coincident);
}
bool advance() {
@@ -1029,18 +1343,6 @@
return fContour->fSegments[fIndex].bounds();
}
- void checkForMultipleCoincidence() const {
- if (fContour->fSegments[fIndex].coincidentCount() > 0) {
- fContour->checkMultiple();
- }
- }
-
- int coincidentT(double newT, const Work& other, CoincidentType type) {
- fContour->containsIntercepts();
- return fContour->fSegments[fIndex].coincidentT(newT,
- other.fContour->fSegments[other.fIndex], (bool) type);
- }
-
const SkPoint* cubic() const {
return fCubic;
}
@@ -1314,47 +1616,27 @@
SkASSERT(0);
}
// in addition to recording T values, record matching segment
- int pt = 0;
- if (pts == 2 && wn.segmentType() <= Work::kLine_Segment
- && wt.segmentType() <= Work::kLine_Segment) {
- wt.checkForMultipleCoincidence();
- wn.checkForMultipleCoincidence();
- // see if segment have same (combo) or opposite (empty) winding
- int testTAt;
- if ((ts.fT[0][0] < ts.fT[0][1]) ^ (ts.fT[1][0] < ts.fT[1][1])
- || winding == 1) { // even-odd
- testTAt = wt.coincidentT(ts.fT[swap][0], wn, Work::kEmpty);
- } else {
- testTAt = wt.coincidentT(ts.fT[swap][0], wn, Work::kCombo);
- }
- int nextTAt = wn.coincidentT(ts.fT[!swap][0], wn, Work::kEmpty);
- wt.addOtherT(testTAt, ts.fT[!swap][0]);
- wn.addOtherT(nextTAt, ts.fT[swap][0]);
- pt = 1;
- }
- for (; pt < pts; ++pt) {
+ int coincident = pts == 2 && wn.segmentType() <= Work::kLine_Segment
+ && wt.segmentType() <= Work::kLine_Segment ? -1 :0;
+ for (int pt = 0; pt < pts; ++pt) {
SkASSERT(ts.fT[0][pt] >= 0 && ts.fT[0][pt] <= 1);
SkASSERT(ts.fT[1][pt] >= 0 && ts.fT[1][pt] <= 1);
- int testTAt = wt.addT(ts.fT[swap][pt], wn);
- int nextTAt = wn.addT(ts.fT[!swap][pt], wt);
+ int testTAt = wt.addT(ts.fT[swap][pt], wn, coincident);
+ int nextTAt = wn.addT(ts.fT[!swap][pt], wt, coincident);
wt.addOtherT(testTAt, ts.fT[!swap][pt]);
wn.addOtherT(nextTAt, ts.fT[swap][pt]);
+ coincident = -coincident;
}
} while (wn.advance());
} while (wt.advance());
return true;
}
-// check if a segment is coincident three or more ways, and
// see if coincidence is formed by clipping non-concident segments
static void coincidenceCheck(SkTDArray<Contour*>& contourList, int winding) {
int contourCount = contourList.count();
for (size_t cIndex = 0; cIndex < contourCount; ++cIndex) {
Contour* contour = contourList[cIndex];
- contour->resolveCoincidence();
- }
- for (size_t cIndex = 0; cIndex < contourCount; ++cIndex) {
- Contour* contour = contourList[cIndex];
contour->findTooCloseToCall(winding);
}
}
@@ -1368,16 +1650,51 @@
// is an option, choose first edge that continues the inside.
static void bridge(SkTDArray<Contour*>& contourList) {
- // Start at the top. Above the top is outside, below is inside.
- Contour* topContour = contourList[0];
- Segment& topStart = topContour->topSegment();
- int index;
- const Segment* topSegment = topStart.findTop(index);
+ int contourCount = contourList.count();
+ do {
+ // OPTIMIZATION: not crazy about linear search here to find top active y.
+ // seems like we should break down and do the sort, or maybe sort each
+ // contours' segments?
+ // Once the segment array is built, there's no reason I can think of not to
+ // sort it in Y. hmmm
+ int cIndex = 0;
+ Segment* topStart;
+ do {
+ Contour* topContour = contourList[cIndex];
+ topStart = topContour->topSegment();
+ } while (!topStart && ++cIndex < contourCount);
+ if (!topStart) {
+ break;
+ }
+ SkScalar top = topStart->bounds().fTop;
+ for (int cTest = cIndex + 1; cTest < contourCount; ++cTest) {
+ Contour* contour = contourList[cTest];
+ if (top < contour->bounds().fTop) {
+ continue;
+ }
+ Segment* test = contour->topSegment();
+ if (top > test->bounds().fTop) {
+ cIndex = cTest;
+ topStart = test;
+ top = test->bounds().fTop;
+ }
+ }
+ int index;
+ const Segment* topSegment = topStart->findTop(index);
+ // Start at the top. Above the top is outside, below is inside.
+ // follow edges to intersection
+ // at intersection, stay on outside, but mark remaining edges as inside
+ // or, only mark first pair as inside?
+ // how is this going to work for contained (but not intersecting)
+ // segments?
// start here ;
// find span
// mark neighbors winding coverage
// output span
// mark span as processed
+
+ } while (true);
+
}