virtual void handlePath(SkCanvas* canvas, const SkPath& path,
const SkPaint& paint, int N) override {
SkPoint pts[2];
if (!path.isLine(pts) || pts[0].fY != pts[1].fY) {
this->INHERITED::handlePath(canvas, path, paint, N);
} else {
SkRect rect;
rect.fLeft = pts[0].fX;
rect.fTop = pts[0].fY - paint.getStrokeWidth() / 2;
rect.fRight = rect.fLeft + SkIntToScalar(fWidth);
rect.fBottom = rect.fTop + paint.getStrokeWidth();
SkPaint p(paint);
p.setStyle(SkPaint::kFill_Style);
p.setPathEffect(nullptr);
int count = SkScalarRoundToInt((pts[1].fX - pts[0].fX) / (2*fWidth));
SkScalar dx = SkIntToScalar(2 * fWidth);
for (int i = 0; i < N*10; ++i) {
SkRect r = rect;
for (int j = 0; j < count; ++j) {
canvas->drawRect(r, p);
r.offset(dx, 0);
}
}
}
}
// Only handles lines for now. If returns true, dstPath is the new (smaller)
// path. If returns false, then dstPath parameter is ignored.
static bool cull_path(const SkPath& srcPath, const SkStrokeRec& rec,
const SkRect* cullRect, SkScalar intervalLength,
SkPath* dstPath) {
if (nullptr == cullRect) {
return false;
}
SkPoint pts[2];
if (!srcPath.isLine(pts)) {
return false;
}
SkRect bounds = *cullRect;
outset_for_stroke(&bounds, rec);
SkScalar dx = pts[1].x() - pts[0].x();
SkScalar dy = pts[1].y() - pts[0].y();
// just do horizontal lines for now (lazy)
if (dy) {
return false;
}
SkScalar minX = pts[0].fX;
SkScalar maxX = pts[1].fX;
if (dx < 0) {
SkTSwap(minX, maxX);
}
SkASSERT(minX <= maxX);
if (maxX < bounds.fLeft || minX > bounds.fRight) {
return false;
}
// Now we actually perform the chop, removing the excess to the left and
// right of the bounds (keeping our new line "in phase" with the dash,
// hence the (mod intervalLength).
if (minX < bounds.fLeft) {
minX = bounds.fLeft - SkScalarMod(bounds.fLeft - minX,
intervalLength);
}
if (maxX > bounds.fRight) {
maxX = bounds.fRight + SkScalarMod(maxX - bounds.fRight,
intervalLength);
}
SkASSERT(maxX >= minX);
if (dx < 0) {
SkTSwap(minX, maxX);
}
pts[0].fX = minX;
pts[1].fX = maxX;
dstPath->moveTo(pts[0]);
dstPath->lineTo(pts[1]);
return true;
}
bool init(const SkPath& src, SkPath* dst, SkStrokeRec* rec,
int intervalCount, SkScalar intervalLength) {
if (rec->isHairlineStyle() || !src.isLine(fPts)) {
return false;
}
// can relax this in the future, if we handle square and round caps
if (SkPaint::kButt_Cap != rec->getCap()) {
return false;
}
SkScalar pathLength = SkPoint::Distance(fPts[0], fPts[1]);
fTangent = fPts[1] - fPts[0];
if (fTangent.isZero()) {
return false;
}
fPathLength = pathLength;
fTangent.scale(SkScalarInvert(pathLength));
fTangent.rotateCCW(&fNormal);
fNormal.scale(SkScalarHalf(rec->getWidth()));
// now estimate how many quads will be added to the path
// resulting segments = pathLen * intervalCount / intervalLen
// resulting points = 4 * segments
SkScalar ptCount = SkScalarMulDiv(pathLength,
SkIntToScalar(intervalCount),
intervalLength);
ptCount = SkTMin(ptCount, SkDashPath::kMaxDashCount);
int n = SkScalarCeilToInt(ptCount) << 2;
dst->incReserve(n);
// we will take care of the stroking
rec->setFillStyle();
return true;
}
// Currently asPoints is more restrictive then it needs to be. In the future
// we need to:
// allow kRound_Cap capping (could allow rotations in the matrix with this)
// allow paths to be returned
bool SkDashPathEffect::asPoints(PointData* results,
const SkPath& src,
const SkStrokeRec& rec,
const SkMatrix& matrix,
const SkRect* cullRect) const {
// width < 0 -> fill && width == 0 -> hairline so requiring width > 0 rules both out
if (fInitialDashLength < 0 || 0 >= rec.getWidth()) {
return false;
}
// TODO: this next test could be eased up. We could allow any number of
// intervals as long as all the ons match and all the offs match.
// Additionally, they do not necessarily need to be integers.
// We cannot allow arbitrary intervals since we want the returned points
// to be uniformly sized.
if (fCount != 2 ||
!SkScalarNearlyEqual(fIntervals[0], fIntervals[1]) ||
!SkScalarIsInt(fIntervals[0]) ||
!SkScalarIsInt(fIntervals[1])) {
return false;
}
SkPoint pts[2];
if (!src.isLine(pts)) {
return false;
}
// TODO: this test could be eased up to allow circles
if (SkPaint::kButt_Cap != rec.getCap()) {
return false;
}
// TODO: this test could be eased up for circles. Rotations could be allowed.
if (!matrix.rectStaysRect()) {
return false;
}
// See if the line can be limited to something plausible.
if (!cull_line(pts, rec, matrix, cullRect, fIntervalLength)) {
return false;
}
SkScalar length = SkPoint::Distance(pts[1], pts[0]);
SkVector tangent = pts[1] - pts[0];
if (tangent.isZero()) {
return false;
}
tangent.scale(SkScalarInvert(length));
// TODO: make this test for horizontal & vertical lines more robust
bool isXAxis = true;
if (SkScalarNearlyEqual(SK_Scalar1, tangent.fX) ||
SkScalarNearlyEqual(-SK_Scalar1, tangent.fX)) {
results->fSize.set(SkScalarHalf(fIntervals[0]), SkScalarHalf(rec.getWidth()));
} else if (SkScalarNearlyEqual(SK_Scalar1, tangent.fY) ||
SkScalarNearlyEqual(-SK_Scalar1, tangent.fY)) {
results->fSize.set(SkScalarHalf(rec.getWidth()), SkScalarHalf(fIntervals[0]));
isXAxis = false;
} else if (SkPaint::kRound_Cap != rec.getCap()) {
// Angled lines don't have axis-aligned boxes.
return false;
}
if (results) {
results->fFlags = 0;
SkScalar clampedInitialDashLength = SkMinScalar(length, fInitialDashLength);
if (SkPaint::kRound_Cap == rec.getCap()) {
results->fFlags |= PointData::kCircles_PointFlag;
}
results->fNumPoints = 0;
SkScalar len2 = length;
if (clampedInitialDashLength > 0 || 0 == fInitialDashIndex) {
SkASSERT(len2 >= clampedInitialDashLength);
if (0 == fInitialDashIndex) {
if (clampedInitialDashLength > 0) {
if (clampedInitialDashLength >= fIntervals[0]) {
++results->fNumPoints; // partial first dash
}
len2 -= clampedInitialDashLength;
}
len2 -= fIntervals[1]; // also skip first space
if (len2 < 0) {
len2 = 0;
}
} else {
len2 -= clampedInitialDashLength; // skip initial partial empty
}
}
int numMidPoints = SkScalarFloorToInt(len2 / fIntervalLength);
results->fNumPoints += numMidPoints;
len2 -= numMidPoints * fIntervalLength;
bool partialLast = false;
if (len2 > 0) {
if (len2 < fIntervals[0]) {
partialLast = true;
} else {
++numMidPoints;
++results->fNumPoints;
}
}
results->fPoints = new SkPoint[results->fNumPoints];
SkScalar distance = 0;
int curPt = 0;
if (clampedInitialDashLength > 0 || 0 == fInitialDashIndex) {
SkASSERT(clampedInitialDashLength <= length);
if (0 == fInitialDashIndex) {
if (clampedInitialDashLength > 0) {
// partial first block
SkASSERT(SkPaint::kRound_Cap != rec.getCap()); // can't handle partial circles
SkScalar x = pts[0].fX + SkScalarMul(tangent.fX, SkScalarHalf(clampedInitialDashLength));
SkScalar y = pts[0].fY + SkScalarMul(tangent.fY, SkScalarHalf(clampedInitialDashLength));
SkScalar halfWidth, halfHeight;
if (isXAxis) {
halfWidth = SkScalarHalf(clampedInitialDashLength);
halfHeight = SkScalarHalf(rec.getWidth());
} else {
halfWidth = SkScalarHalf(rec.getWidth());
halfHeight = SkScalarHalf(clampedInitialDashLength);
}
if (clampedInitialDashLength < fIntervals[0]) {
// This one will not be like the others
results->fFirst.addRect(x - halfWidth, y - halfHeight,
x + halfWidth, y + halfHeight);
} else {
SkASSERT(curPt < results->fNumPoints);
results->fPoints[curPt].set(x, y);
++curPt;
}
distance += clampedInitialDashLength;
}
distance += fIntervals[1]; // skip over the next blank block too
} else {
distance += clampedInitialDashLength;
}
}
if (0 != numMidPoints) {
distance += SkScalarHalf(fIntervals[0]);
for (int i = 0; i < numMidPoints; ++i) {
SkScalar x = pts[0].fX + SkScalarMul(tangent.fX, distance);
SkScalar y = pts[0].fY + SkScalarMul(tangent.fY, distance);
SkASSERT(curPt < results->fNumPoints);
results->fPoints[curPt].set(x, y);
++curPt;
distance += fIntervalLength;
}
distance -= SkScalarHalf(fIntervals[0]);
}
if (partialLast) {
// partial final block
SkASSERT(SkPaint::kRound_Cap != rec.getCap()); // can't handle partial circles
SkScalar temp = length - distance;
SkASSERT(temp < fIntervals[0]);
SkScalar x = pts[0].fX + SkScalarMul(tangent.fX, distance + SkScalarHalf(temp));
SkScalar y = pts[0].fY + SkScalarMul(tangent.fY, distance + SkScalarHalf(temp));
SkScalar halfWidth, halfHeight;
if (isXAxis) {
halfWidth = SkScalarHalf(temp);
halfHeight = SkScalarHalf(rec.getWidth());
} else {
halfWidth = SkScalarHalf(rec.getWidth());
halfHeight = SkScalarHalf(temp);
}
results->fLast.addRect(x - halfWidth, y - halfHeight,
x + halfWidth, y + halfHeight);
}
SkASSERT(curPt == results->fNumPoints);
}
return true;
}