Revert "Revert "long rect dash fix with guards""
This reverts commit fa6b6c2d1b613faf72071b99f4b404fa4ee5e076.
Reason for revert: Looks like this was actually caused by another change but happen to fail a test that looked very related to this
Original change's description:
> Revert "long rect dash fix with guards"
>
> This reverts commit 93ceab1b59f06c828cf62aa6a700e7f81620f23d.
>
> Reason for revert: breaking layout test
>
> Original change's description:
> > long rect dash fix with guards
> >
> > long rect dash with guards
> >
> > check dash fix back in with
> > guards against changing
> > chrome layout test results
> >
> > original change clipped against wrong rectangle
> > some of the time, causing tiled drawing to fail.
> > Always clip against outset rectangle.
> >
> > original CL: skia-review.googlesource.com/c/skia/+/84862
> >
> > efficiently dash very large rectangles and very long lines
> > Speed up dashing when lines and rects are absurdly large.
> >
> > Prior to this CL, only horizontal lines were detected.
> >
> > Also folded in a change to handle dashing of zero length lines.
> >
> > TBR=egdaniel@google.com
> > Bug: skia:7311
> > Change-Id: Ic3c68ec8ea35d0597c892c3b26ba7bb077045990
> > Reviewed-on: https://skia-review.googlesource.com/87768
> > Reviewed-by: Cary Clark <caryclark@skia.org>
> > Commit-Queue: Cary Clark <caryclark@skia.org>
>
> TBR=egdaniel@google.com,caryclark@skia.org
>
> Change-Id: I56ef771ccb281887d7381c2bd8a2553acbd30621
> No-Presubmit: true
> No-Tree-Checks: true
> No-Try: true
> Bug: skia:7311
> Reviewed-on: https://skia-review.googlesource.com/88421
> Reviewed-by: Greg Daniel <egdaniel@google.com>
> Commit-Queue: Greg Daniel <egdaniel@google.com>
TBR=egdaniel@google.com,caryclark@skia.org
Change-Id: Iecdd072544e6623bc4de8d5aab1402378112512d
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: skia:7311
Reviewed-on: https://skia-review.googlesource.com/88424
Reviewed-by: Greg Daniel <egdaniel@google.com>
Commit-Queue: Greg Daniel <egdaniel@google.com>
diff --git a/gm/strokes.cpp b/gm/strokes.cpp
index ed13d09..50b940a 100644
--- a/gm/strokes.cpp
+++ b/gm/strokes.cpp
@@ -533,3 +533,33 @@
canvas->drawLine(100, 100, 100, 100, paint);
}
+
+#ifdef PDF_IS_FIXED_SO_THIS_DOESNT_BREAK_IT
+DEF_SIMPLE_GM(longrect_dash, canvas, 250, 250) {
+ canvas->clear(SK_ColorWHITE);
+
+ SkPaint paint;
+ paint.setColor(SkColorSetARGB(255, 0, 0, 0));
+ paint.setStrokeWidth(5);
+ paint.setStrokeCap(SkPaint::kRound_Cap);
+ paint.setStrokeJoin(SkPaint::kBevel_Join);
+ paint.setStyle(SkPaint::kStroke_Style);
+ SkScalar dash_pattern[] = {1, 5};
+ paint.setPathEffect(SkDashPathEffect::Make(dash_pattern, 2, 0));
+ // try all combinations of stretching bounds
+ for (auto left : { 20.f, -100001.f } ) {
+ for (auto top : { 20.f, -100001.f } ) {
+ for (auto right : { 40.f, 100001.f } ) {
+ for (auto bottom : { 40.f, 100001.f } ) {
+ canvas->save();
+ canvas->clipRect({10, 10, 50, 50});
+ canvas->drawRect({left, top, right, bottom}, paint);
+ canvas->restore();
+ canvas->translate(60, 0);
+ }
+ }
+ canvas->translate(-60 * 4, 60);
+ }
+ }
+}
+#endif
diff --git a/src/utils/SkDashPath.cpp b/src/utils/SkDashPath.cpp
index cbfc8f2..8d6c3cf 100644
--- a/src/utils/SkDashPath.cpp
+++ b/src/utils/SkDashPath.cpp
@@ -83,11 +83,95 @@
rect->outset(radius, radius);
}
+#ifndef SK_SUPPORT_LEGACY_DASH_CULL_PATH
+// If line is zero-length, bump out the end by a tiny amount
+// to draw endcaps. The bump factor is sized so that
+// SkPoint::Distance() computes a non-zero length.
+// Offsets SK_ScalarNearlyZero or smaller create empty paths when Iter measures length.
+// Large values are scaled by SK_ScalarNearlyZero so significant bits change.
+static void adjust_zero_length_line(SkPoint pts[2]) {
+ SkASSERT(pts[0] == pts[1]);
+ pts[1].fX += SkTMax(1.001f, pts[1].fX) * SK_ScalarNearlyZero;
+}
+
+static bool clip_line(SkPoint pts[2], const SkRect& bounds, SkScalar intervalLength,
+ SkScalar priorPhase) {
+ SkVector dxy = pts[1] - pts[0];
+
+ // only horizontal or vertical lines
+ if (dxy.fX && dxy.fY) {
+ return false;
+ }
+ int xyOffset = SkToBool(dxy.fY); // 0 to adjust horizontal, 1 to adjust vertical
+
+ SkScalar minXY = (&pts[0].fX)[xyOffset];
+ SkScalar maxXY = (&pts[1].fX)[xyOffset];
+ bool swapped = maxXY < minXY;
+ if (swapped) {
+ SkTSwap(minXY, maxXY);
+ }
+
+ SkASSERT(minXY <= maxXY);
+ SkScalar leftTop = (&bounds.fLeft)[xyOffset];
+ SkScalar rightBottom = (&bounds.fRight)[xyOffset];
+ if (maxXY < leftTop || minXY > rightBottom) {
+ return false;
+ }
+
+ // Now we actually perform the chop, removing the excess to the left/top and
+ // right/bottom of the bounds (keeping our new line "in phase" with the dash,
+ // hence the (mod intervalLength).
+
+ if (minXY < leftTop) {
+ minXY = leftTop - SkScalarMod(leftTop - minXY, intervalLength);
+ if (!swapped) {
+ minXY -= priorPhase; // for rectangles, adjust by prior phase
+ }
+ }
+ if (maxXY > rightBottom) {
+ maxXY = rightBottom + SkScalarMod(maxXY - rightBottom, intervalLength);
+ if (swapped) {
+ maxXY += priorPhase; // for rectangles, adjust by prior phase
+ }
+ }
+
+ SkASSERT(maxXY >= minXY);
+ if (swapped) {
+ SkTSwap(minXY, maxXY);
+ }
+ (&pts[0].fX)[xyOffset] = minXY;
+ (&pts[1].fX)[xyOffset] = maxXY;
+
+ if (minXY == maxXY) {
+ adjust_zero_length_line(pts);
+ }
+ return true;
+}
+
+static bool contains_inclusive(const SkRect& rect, const SkPoint& pt) {
+ return rect.fLeft <= pt.fX && pt.fX <= rect.fRight &&
+ rect.fTop <= pt.fY && pt.fY <= rect.fBottom;
+}
+
+// Returns true is b is between a and c, that is: a <= b <= c, or a >= b >= c.
+// Can perform this test with one branch by observing that, relative to b,
+// the condition is true only if one side is positive and one side is negative.
+// If the numbers are very small, the optimization may return the wrong result
+// because the multiply may generate a zero where the simple compare does not.
+// For this reason the assert does not fire when all three numbers are near zero.
+static bool between(SkScalar a, SkScalar b, SkScalar c) {
+ SkASSERT(((a <= b && b <= c) || (a >= b && b >= c)) == ((a - b) * (c - b) <= 0)
+ || (SkScalarNearlyZero(a) && SkScalarNearlyZero(b) && SkScalarNearlyZero(c)));
+ return (a - b) * (c - b) <= 0;
+}
+#endif
+
// 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) {
+#ifdef SK_SUPPORT_LEGACY_DASH_CULL_PATH
if (nullptr == cullRect) {
return false;
}
@@ -146,6 +230,53 @@
if (minX == maxX) {
pts[1].fX += maxX * FLT_EPSILON * 32; // 16 instead of 32 does not draw; length stays zero
}
+#else // !SK_SUPPORT_LEGACY_DASH_CULL_PATH
+ SkPoint pts[4];
+ if (nullptr == cullRect) {
+ if (srcPath.isLine(pts) && pts[0] == pts[1]) {
+ adjust_zero_length_line(pts);
+ } else {
+ return false;
+ }
+ } else {
+ SkRect bounds;
+ bool isLine = srcPath.isLine(pts);
+ bool isRect = !isLine && srcPath.isRect(nullptr);
+ if (!isLine && !isRect) {
+ return false;
+ }
+ bounds = *cullRect;
+ outset_for_stroke(&bounds, rec);
+ if (isRect) {
+ // break rect into four lines, and call each one separately
+ SkPath::Iter iter(srcPath, false);
+ SkAssertResult(SkPath::kMove_Verb == iter.next(pts));
+ SkScalar priorLength = 0;
+ while (SkPath::kLine_Verb == iter.next(pts)) {
+ SkVector v = pts[1] - pts[0];
+ // if line is entirely outside clip rect, skip it
+ if (v.fX ? between(bounds.fTop, pts[0].fY, bounds.fBottom) :
+ between(bounds.fLeft, pts[0].fX, bounds.fRight)) {
+ bool skipMoveTo = contains_inclusive(bounds, pts[0]);
+ if (clip_line(pts, bounds, intervalLength,
+ SkScalarMod(priorLength, intervalLength))) {
+ if (0 == priorLength || !skipMoveTo) {
+ dstPath->moveTo(pts[0]);
+ }
+ dstPath->lineTo(pts[1]);
+ }
+ }
+ // keep track of all prior lengths to set phase of next line
+ priorLength += SkScalarAbs(v.fX ? v.fX : v.fY);
+ }
+ return !dstPath->isEmpty();
+ }
+ SkASSERT(isLine);
+ if (!clip_line(pts, bounds, intervalLength, 0)) {
+ return false;
+ }
+ }
+#endif
dstPath->moveTo(pts[0]);
dstPath->lineTo(pts[1]);
return true;