detect more than one loop in computeconvexity
git-svn-id: http://skia.googlecode.com/svn/trunk@1326 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/core/SkPath.cpp b/src/core/SkPath.cpp
index fa6b3b9..d8e2c4c 100644
--- a/src/core/SkPath.cpp
+++ b/src/core/SkPath.cpp
@@ -1401,12 +1401,16 @@
return value < 0 ? -1 : (value > 0);
}
+static int sign(SkScalar x) { return x < 0 ? -1 : 1; }
+
static int CrossProductSign(const SkVector& a, const SkVector& b) {
return SkScalarSign(SkPoint::CrossProduct(a, b));
}
// only valid for a single contour
struct Convexicator {
+ int fDx, fDy, fSx, fSy;
+
Convexicator() : fPtCount(0), fConvexity(SkPath::kUnknown_Convexity) {
fSign = 0;
// warnings
@@ -1414,6 +1418,9 @@
fVec0.set(0, 0);
fVec1.set(0, 0);
fFirstVec.set(0, 0);
+
+ fDx = fDy = 0;
+ fSx = fSy = 2;
}
SkPath::Convexity getConvexity() const { return fConvexity; }
@@ -1436,6 +1443,17 @@
SkASSERT(fPtCount > 2);
this->addVec(vec);
}
+
+ int sx = sign(vec.fX);
+ int sy = sign(vec.fY);
+ fDx += (sx != fSx);
+ fDy += (sy != fSy);
+ fSx = sx;
+ fSy = sy;
+
+ if (fDx > 3 || fDy > 3) {
+ fConvexity = SkPath::kConcave_Convexity;
+ }
}
}
}
diff --git a/tests/PathTest.cpp b/tests/PathTest.cpp
index 82f230d..3884308 100644
--- a/tests/PathTest.cpp
+++ b/tests/PathTest.cpp
@@ -86,7 +86,7 @@
spiral.lineTo(.5,.5);
spiral.lineTo(.5,.75);
spiral.close();
-// check_convexity(reporter, spiral, SkPath::kConcave_Convexity);
+ check_convexity(reporter, spiral, SkPath::kConcave_Convexity);
SkPath dent;
dent.moveTo(0, 0);
@@ -157,7 +157,7 @@
} gRec[] = {
{ "0 0", SkPath::kUnknown_Convexity },
{ "0 0 10 10", SkPath::kUnknown_Convexity },
- { "0 0 10 10 20 20 0 0 10 10", SkPath::kUnknown_Convexity },
+ { "0 0 10 10 20 20 0 0 10 10", SkPath::kConcave_Convexity },
{ "0 0 10 10 10 20", SkPath::kConvex_Convexity },
{ "0 0 10 10 10 0", SkPath::kConvex_Convexity },
{ "0 0 10 10 10 0 0 10", SkPath::kConcave_Convexity },