static bool is_linear_inner(const SkDQuad& q1, double t1s, double t1e, const SkDQuad& q2,
double t2s, double t2e, SkIntersections* i, bool* subDivide) {
SkDQuad hull = q1.subDivide(t1s, t1e);
SkDLine line = {{hull[2], hull[0]}};
const SkDLine* testLines[] = { &line, (const SkDLine*) &hull[0], (const SkDLine*) &hull[1] };
const size_t kTestCount = SK_ARRAY_COUNT(testLines);
SkSTArray<kTestCount * 2, double, true> tsFound;
for (size_t index = 0; index < kTestCount; ++index) {
SkIntersections rootTs;
rootTs.allowNear(false);
int roots = rootTs.intersect(q2, *testLines[index]);
for (int idx2 = 0; idx2 < roots; ++idx2) {
double t = rootTs[0][idx2];
#ifdef SK_DEBUG
SkDPoint qPt = q2.ptAtT(t);
SkDPoint lPt = testLines[index]->ptAtT(rootTs[1][idx2]);
SkASSERT(qPt.approximatelyEqual(lPt));
#endif
if (approximately_negative(t - t2s) || approximately_positive(t - t2e)) {
continue;
}
tsFound.push_back(rootTs[0][idx2]);
}
}
int tCount = tsFound.count();
if (tCount <= 0) {
return true;
}
double tMin, tMax;
if (tCount == 1) {
tMin = tMax = tsFound[0];
} else {
SkASSERT(tCount > 1);
SkTQSort<double>(tsFound.begin(), tsFound.end() - 1);
tMin = tsFound[0];
tMax = tsFound[tsFound.count() - 1];
}
SkDPoint end = q2.ptAtT(t2s);
bool startInTriangle = hull.pointInHull(end);
if (startInTriangle) {
tMin = t2s;
}
end = q2.ptAtT(t2e);
bool endInTriangle = hull.pointInHull(end);
if (endInTriangle) {
tMax = t2e;
}
int split = 0;
SkDVector dxy1, dxy2;
if (tMin != tMax || tCount > 2) {
dxy2 = q2.dxdyAtT(tMin);
for (int index = 1; index < tCount; ++index) {
dxy1 = dxy2;
dxy2 = q2.dxdyAtT(tsFound[index]);
double dot = dxy1.dot(dxy2);
if (dot < 0) {
split = index - 1;
break;
}
}
}
if (split == 0) { // there's one point
if (add_intercept(q1, q2, tMin, tMax, i, subDivide)) {
return true;
}
i->swap();
return is_linear_inner(q2, tMin, tMax, q1, t1s, t1e, i, subDivide);
}
// At this point, we have two ranges of t values -- treat each separately at the split
bool result;
if (add_intercept(q1, q2, tMin, tsFound[split - 1], i, subDivide)) {
result = true;
} else {
i->swap();
result = is_linear_inner(q2, tMin, tsFound[split - 1], q1, t1s, t1e, i, subDivide);
}
if (add_intercept(q1, q2, tsFound[split], tMax, i, subDivide)) {
result = true;
} else {
i->swap();
result |= is_linear_inner(q2, tsFound[split], tMax, q1, t1s, t1e, i, subDivide);
}
return result;
}
void SkIntersections::cubicNearEnd(const SkDCubic& cubic1, bool start, const SkDCubic& cubic2,
const SkDRect& bounds2) {
SkDLine line;
int t1Index = start ? 0 : 3;
double testT = (double) !start;
// don't bother if the two cubics are connnected
static const int kPointsInCubic = 4; // FIXME: move to DCubic, replace '4' with this
static const int kMaxLineCubicIntersections = 3;
SkSTArray<(kMaxLineCubicIntersections - 1) * kMaxLineCubicIntersections, double, true> tVals;
line[0] = cubic1[t1Index];
// this variant looks for intersections with the end point and lines parallel to other points
for (int index = 0; index < kPointsInCubic; ++index) {
if (index == t1Index) {
continue;
}
SkDVector dxy1 = cubic1[index] - line[0];
dxy1 /= SkDCubic::gPrecisionUnit;
line[1] = line[0] + dxy1;
SkDRect lineBounds;
lineBounds.setBounds(line);
if (!bounds2.intersects(&lineBounds)) {
continue;
}
SkIntersections local;
if (!local.intersect(cubic2, line)) {
continue;
}
for (int idx2 = 0; idx2 < local.used(); ++idx2) {
double foundT = local[0][idx2];
if (approximately_less_than_zero(foundT)
|| approximately_greater_than_one(foundT)) {
continue;
}
if (local.pt(idx2).approximatelyEqual(line[0])) {
if (swapped()) { // FIXME: insert should respect swap
insert(foundT, testT, line[0]);
} else {
insert(testT, foundT, line[0]);
}
} else {
tVals.push_back(foundT);
}
}
}
if (tVals.count() == 0) {
return;
}
SkTQSort<double>(tVals.begin(), tVals.end() - 1);
double tMin1 = start ? 0 : 1 - LINE_FRACTION;
double tMax1 = start ? LINE_FRACTION : 1;
int tIdx = 0;
do {
int tLast = tIdx;
while (tLast + 1 < tVals.count() && roughly_equal(tVals[tLast + 1], tVals[tIdx])) {
++tLast;
}
double tMin2 = SkTMax(tVals[tIdx] - LINE_FRACTION, 0.0);
double tMax2 = SkTMin(tVals[tLast] + LINE_FRACTION, 1.0);
int lastUsed = used();
if (start ? tMax1 < tMin2 : tMax2 < tMin1) {
::intersect(cubic1, tMin1, tMax1, cubic2, tMin2, tMax2, 1, *this);
}
if (lastUsed == used()) {
tMin2 = SkTMax(tVals[tIdx] - (1.0 / SkDCubic::gPrecisionUnit), 0.0);
tMax2 = SkTMin(tVals[tLast] + (1.0 / SkDCubic::gPrecisionUnit), 1.0);
if (start ? tMax1 < tMin2 : tMax2 < tMin1) {
::intersect(cubic1, tMin1, tMax1, cubic2, tMin2, tMax2, 1, *this);
}
}
tIdx = tLast + 1;
} while (tIdx < tVals.count());
return;
}
// FIXME: this and find chase should be merge together, along with
// other code that walks winding in angles
// OPTIMIZATION: Probably, the walked winding should be rolled into the angle structure
// so it isn't duplicated by walkers like this one
static SkOpSegment* findChaseOp(SkTDArray<SkOpSpan*>& chase, int& nextStart, int& nextEnd) {
while (chase.count()) {
SkOpSpan* span;
chase.pop(&span);
const SkOpSpan& backPtr = span->fOther->span(span->fOtherIndex);
SkOpSegment* segment = backPtr.fOther;
nextStart = backPtr.fOtherIndex;
SkSTArray<SkOpAngle::kStackBasedCount, SkOpAngle, true> angles;
int done = 0;
if (segment->activeAngle(nextStart, &done, &angles)) {
SkOpAngle* last = angles.end() - 1;
nextStart = last->start();
nextEnd = last->end();
#if TRY_ROTATE
*chase.insert(0) = span;
#else
*chase.append() = span;
#endif
return last->segment();
}
if (done == angles.count()) {
continue;
}
SkSTArray<SkOpAngle::kStackBasedCount, SkOpAngle*, true> sorted;
bool sortable = SkOpSegment::SortAngles(angles, &sorted,
SkOpSegment::kMayBeUnordered_SortAngleKind);
int angleCount = sorted.count();
#if DEBUG_SORT
sorted[0]->segment()->debugShowSort(__FUNCTION__, sorted, 0, sortable);
#endif
if (!sortable) {
continue;
}
// find first angle, initialize winding to computed fWindSum
int firstIndex = -1;
const SkOpAngle* angle;
bool foundAngle = true;
do {
++firstIndex;
if (firstIndex >= angleCount) {
foundAngle = false;
break;
}
angle = sorted[firstIndex];
segment = angle->segment();
} while (segment->windSum(angle) == SK_MinS32);
if (!foundAngle) {
continue;
}
#if DEBUG_SORT
segment->debugShowSort(__FUNCTION__, sorted, firstIndex, sortable);
#endif
int sumMiWinding = segment->updateWindingReverse(angle);
int sumSuWinding = segment->updateOppWindingReverse(angle);
if (segment->operand()) {
SkTSwap<int>(sumMiWinding, sumSuWinding);
}
int nextIndex = firstIndex + 1;
int lastIndex = firstIndex != 0 ? firstIndex : angleCount;
SkOpSegment* first = NULL;
do {
SkASSERT(nextIndex != firstIndex);
if (nextIndex == angleCount) {
nextIndex = 0;
}
angle = sorted[nextIndex];
segment = angle->segment();
int start = angle->start();
int end = angle->end();
int maxWinding, sumWinding, oppMaxWinding, oppSumWinding;
segment->setUpWindings(start, end, &sumMiWinding, &sumSuWinding,
&maxWinding, &sumWinding, &oppMaxWinding, &oppSumWinding);
if (!segment->done(angle)) {
if (!first) {
first = segment;
nextStart = start;
nextEnd = end;
}
(void) segment->markAngle(maxWinding, sumWinding, oppMaxWinding,
oppSumWinding, angle);
}
} while (++nextIndex != lastIndex);
if (first) {
#if TRY_ROTATE
*chase.insert(0) = span;
#else
*chase.append() = span;
#endif
return first;
}
}
return NULL;
}
SkOpSegment* FindChase(SkTDArray<SkOpSpan*>& chase, int& tIndex, int& endIndex) {
while (chase.count()) {
SkOpSpan* span;
chase.pop(&span);
const SkOpSpan& backPtr = span->fOther->span(span->fOtherIndex);
SkOpSegment* segment = backPtr.fOther;
tIndex = backPtr.fOtherIndex;
SkSTArray<SkOpAngle::kStackBasedCount, SkOpAngle, true> angles;
int done = 0;
if (segment->activeAngle(tIndex, &done, &angles)) {
SkOpAngle* last = angles.end() - 1;
tIndex = last->start();
endIndex = last->end();
#if TRY_ROTATE
*chase.insert(0) = span;
#else
*chase.append() = span;
#endif
return last->segment();
}
if (done == angles.count()) {
continue;
}
SkSTArray<SkOpAngle::kStackBasedCount, SkOpAngle*, true> sorted;
bool sortable = SkOpSegment::SortAngles(angles, &sorted,
SkOpSegment::kMayBeUnordered_SortAngleKind);
int angleCount = sorted.count();
#if DEBUG_SORT
sorted[0]->segment()->debugShowSort(__FUNCTION__, sorted, 0, 0, 0);
#endif
if (!sortable) {
continue;
}
// find first angle, initialize winding to computed fWindSum
int firstIndex = -1;
const SkOpAngle* angle;
int winding;
do {
angle = sorted[++firstIndex];
segment = angle->segment();
winding = segment->windSum(angle);
} while (winding == SK_MinS32);
int spanWinding = segment->spanSign(angle->start(), angle->end());
#if DEBUG_WINDING
SkDebugf("%s winding=%d spanWinding=%d\n",
__FUNCTION__, winding, spanWinding);
#endif
// turn span winding into contour winding
if (spanWinding * winding < 0) {
winding += spanWinding;
}
#if DEBUG_SORT
segment->debugShowSort(__FUNCTION__, sorted, firstIndex, winding, 0);
#endif
// we care about first sign and whether wind sum indicates this
// edge is inside or outside. Maybe need to pass span winding
// or first winding or something into this function?
// advance to first undone angle, then return it and winding
// (to set whether edges are active or not)
int nextIndex = firstIndex + 1;
int lastIndex = firstIndex != 0 ? firstIndex : angleCount;
angle = sorted[firstIndex];
winding -= angle->segment()->spanSign(angle);
do {
SkASSERT(nextIndex != firstIndex);
if (nextIndex == angleCount) {
nextIndex = 0;
}
angle = sorted[nextIndex];
segment = angle->segment();
int maxWinding = winding;
winding -= segment->spanSign(angle);
#if DEBUG_SORT
SkDebugf("%s id=%d maxWinding=%d winding=%d sign=%d\n", __FUNCTION__,
segment->debugID(), maxWinding, winding, angle->sign());
#endif
tIndex = angle->start();
endIndex = angle->end();
int lesser = SkMin32(tIndex, endIndex);
const SkOpSpan& nextSpan = segment->span(lesser);
if (!nextSpan.fDone) {
// FIXME: this be wrong? assign startWinding if edge is in
// same direction. If the direction is opposite, winding to
// assign is flipped sign or +/- 1?
if (SkOpSegment::UseInnerWinding(maxWinding, winding)) {
maxWinding = winding;
}
segment->markAndChaseWinding(angle, maxWinding, 0);
break;
}
} while (++nextIndex != lastIndex);
*chase.insert(0) = span;
return segment;
}
return NULL;
}
