path ops work in progress
path ops work in progress
BUG=
Review URL: https://codereview.chromium.org/21359002
git-svn-id: http://skia.googlecode.com/svn/trunk@11291 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/pathops/SkDLineIntersection.cpp b/src/pathops/SkDLineIntersection.cpp
index 46118429..4b818dc 100644
--- a/src/pathops/SkDLineIntersection.cpp
+++ b/src/pathops/SkDLineIntersection.cpp
@@ -35,21 +35,18 @@
}
int SkIntersections::intersectRay(const SkDLine& a, const SkDLine& b) {
- double axLen = a[1].fX - a[0].fX;
- double ayLen = a[1].fY - a[0].fY;
- double bxLen = b[1].fX - b[0].fX;
- double byLen = b[1].fY - b[0].fY;
+ SkDVector aLen = a[1] - a[0];
+ SkDVector bLen = b[1] - b[0];
/* Slopes match when denom goes to zero:
axLen / ayLen == bxLen / byLen
(ayLen * byLen) * axLen / ayLen == (ayLen * byLen) * bxLen / byLen
byLen * axLen == ayLen * bxLen
byLen * axLen - ayLen * bxLen == 0 ( == denom )
*/
- double denom = byLen * axLen - ayLen * bxLen;
- double ab0y = a[0].fY - b[0].fY;
- double ab0x = a[0].fX - b[0].fX;
- double numerA = ab0y * bxLen - byLen * ab0x;
- double numerB = ab0y * axLen - ayLen * ab0x;
+ double denom = bLen.fY * aLen.fX - aLen.fY * bLen.fX;
+ SkDVector ab0 = a[0] - b[0];
+ double numerA = ab0.fY * bLen.fX - bLen.fY * ab0.fX;
+ double numerB = ab0.fY * aLen.fX - aLen.fY * ab0.fX;
numerA /= denom;
numerB /= denom;
int used;
@@ -63,8 +60,8 @@
axLen * (ay - ax * ayLen / axLen) == axLen * (by - bx * ayLen / axLen)
axLen * ay - ax * ayLen == axLen * by - bx * ayLen
*/
- if (!AlmostEqualUlps(axLen * a[0].fY - ayLen * a[0].fX,
- axLen * b[0].fY - ayLen * b[0].fX)) {
+ if (!AlmostEqualUlps(aLen.fX * a[0].fY - aLen.fY * a[0].fX,
+ aLen.fX * b[0].fY - aLen.fY * b[0].fX)) {
return fUsed = 0;
}
// there's no great answer for intersection points for coincident rays, but return something
@@ -106,8 +103,8 @@
double ayBxLen = ayLen * bxLen;
// detect parallel lines the same way here and in SkOpAngle operator <
// so that non-parallel means they are also sortable
- bool parallel = AlmostEqualUlps(axByLen, ayBxLen);
- if (!parallel) {
+ bool unparallel = NotAlmostEqualUlps(axByLen, ayBxLen);
+ if (unparallel) {
double ab0y = a[0].fY - b[0].fY;
double ab0x = a[0].fX - b[0].fX;
double numerA = ab0y * bxLen - byLen * ab0x;
@@ -119,7 +116,7 @@
computePoints(a, 1);
}
}
- if (fAllowNear || parallel) {
+ if (fAllowNear || !unparallel) {
for (int iA = 0; iA < 2; ++iA) {
if ((t = b.nearPoint(a[iA])) >= 0) {
insert(iA, t, a[iA]);
@@ -131,6 +128,17 @@
}
}
}
+ while (fUsed > 2) {
+ removeOne(1);
+ }
+ if (fUsed == 2 && unparallel) {
+ bool startMatch = fT[0][0] == 0 || fT[1][0] == 0 || fT[1][0] == 1;
+ bool endMatch = fT[0][1] == 1 || fT[1][1] == 0 || fT[1][1] == 1;
+ if (!startMatch && !endMatch) {
+ SkASSERT(startMatch || endMatch);
+ removeOne(endMatch);
+ }
+ }
return fUsed;
}