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yet another path is rect exploit

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This one accumulates the othershoot when all four sides
have the same direction, and the final side when closed
should cause the overshoot to be ignored.

Docs-Preview: https://skia.org/?cl=121787
Bug: 824145,skia:7792
Change-Id: I71ea0fcdd0f03a4fcac224b57220c65c321112f6
Reviewed-on: https://skia-review.googlesource.com/121787
Commit-Queue: Cary Clark <caryclark@skia.org>
Commit-Queue: Robert Phillips <robertphillips@google.com>
Auto-Submit: Cary Clark <caryclark@skia.org>
Reviewed-by: Robert Phillips <robertphillips@google.com>
This commit is contained in:
Cary Clark 2018-04-17 09:30:14 -04:00 committed by Skia Commit-Bot
parent 8954d097c3
commit a7651567ca
3 changed files with 26 additions and 1 deletions
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11
gm/pathfill.cpp
View File

@ -547,4 +547,15 @@ DEF_SIMPLE_GM(bug7792, canvas, 600, 800) {
path.moveTo(75, 75);
path.close();
canvas->drawPath(path, p);
// from skbug.com/7792#c31
canvas->translate(200, 0);
path.reset();
path.moveTo(75, 75);
path.lineTo(150, 75);
path.lineTo(150, 150);
path.lineTo(75, 150);
path.lineTo(75, 10);
path.moveTo(75, 75);
path.close();
canvas->drawPath(path, p);
}

7
src/core/SkPath.cpp
View File

@ -453,6 +453,7 @@ bool SkPath::isRectContour(bool allowPartial, int* currVerb, const SkPoint** pts
SkPoint lineStart; // used to construct line from previous point
const SkPoint* firstPt = nullptr; // first point in the rect (last of first moves)
const SkPoint* lastPt = nullptr; // last point in the rect (last of lines or first if closed)
const SkPoint* lastCountedPt = nullptr; // point creating 3rd corner
const SkPoint* pts = *ptsPtr;
const SkPoint* savePts = nullptr; // used to allow caller to iterate through a pair of rects
lineStart.set(0, 0);
@ -473,6 +474,9 @@ bool SkPath::isRectContour(bool allowPartial, int* currVerb, const SkPoint** pts
accumulatingRect = false;
case kLine_Verb: {
if (accumulatingRect) {
lastCountedPt = pts;
}
if (kClose_Verb != verb) {
lastPt = pts;
}
SkPoint lineEnd = kClose_Verb == verb ? *firstPt : *pts++;
@ -512,6 +516,7 @@ bool SkPath::isRectContour(bool allowPartial, int* currVerb, const SkPoint** pts
if ((directions[0] ^ directions[2]) != 2) {
return false;
}
accumulatingRect = false;
} else if (corners == 4) {
if ((directions[1] ^ directions[3]) != 2) {
return false;
@ -574,7 +579,7 @@ addMissingClose:
*ptsPtr = savePts;
}
if (result && rect) {
ptrdiff_t count = lastPt - firstPt + 1;
ptrdiff_t count = lastCountedPt - firstPt + 1;
rect->set(firstPt, (int) count);
}
if (result && isClosed) {

9
tests/PathTest.cpp
View File

@ -5003,4 +5003,13 @@ DEF_TEST(Path_isRect, reporter) {
SkPoint points29[] = { {75, 75}, {150, 75}, {150, 150}, {75, 150}, {75, 250}, {75, 75} };
path = makePath2(points29, verbs29, SK_ARRAY_COUNT(verbs29));
REPORTER_ASSERT(reporter, !path.isRect(&rect, nullptr, nullptr));
// isolated from skbug.com/7792#c31
SkPath::Verb verbs31[] = { SkPath::kMove_Verb, SkPath::kLine_Verb, SkPath::kLine_Verb,
SkPath::kLine_Verb, SkPath::kLine_Verb, SkPath::kMove_Verb,
SkPath::kClose_Verb };
SkPoint points31[] = { {75, 75}, {150, 75}, {150, 150}, {75, 150}, {75, 10}, {75, 75} };
path = makePath2(points31, verbs31, SK_ARRAY_COUNT(verbs31));
REPORTER_ASSERT(reporter, path.isRect(&rect, nullptr, nullptr));
compare.set(&points31[0], 4);
REPORTER_ASSERT(reporter, rect == compare);
}