// intersect the end of the cubic with the other. Try lines from the end to control and opposite
// end to determine range of t on opposite cubic.
static void intersectEnd(const SkDCubic& cubic1, bool start, const SkDCubic& cubic2,
const SkDRect& bounds2, SkIntersections& i) {
SkDLine line;
int t1Index = start ? 0 : 3;
line[0] = cubic1[t1Index];
// don't bother if the two cubics are connnected
SkTDArray<double> tVals; // OPTIMIZE: replace with hard-sized array
for (int index = 0; index < 4; ++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 (i.swapped()) { // FIXME: insert should respect swap
i.insert(foundT, start ? 0 : 1, line[0]);
} else {
i.insert(start ? 0 : 1, foundT, line[0]);
}
} else {
*tVals.append() = local[0][idx2];
}
}
}
if (tVals.count() == 0) {
return;
}
QSort<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<double>(tVals[tIdx] - LINE_FRACTION, 0.0);
double tMax2 = SkTMin<double>(tVals[tLast] + LINE_FRACTION, 1.0);
int lastUsed = i.used();
intersect(cubic1, tMin1, tMax1, cubic2, tMin2, tMax2, 1, i);
if (lastUsed == i.used()) {
tMin2 = SkTMax<double>(tVals[tIdx] - (1.0 / SkDCubic::gPrecisionUnit), 0.0);
tMax2 = SkTMin<double>(tVals[tLast] + (1.0 / SkDCubic::gPrecisionUnit), 1.0);
intersect(cubic1, tMin1, tMax1, cubic2, tMin2, tMax2, 1, i);
}
tIdx = tLast + 1;
} while (tIdx < tVals.count());
return;
}
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;
}
