This CL effectively reverts:
r5997 Altered arcTo's canonical points to (usually) be convex (https://codereview.appspot.com/6709051/)
r9928 GM (and fix) for drawArc capping issue (https://codereview.chromium.org/18271003/)
Instead of pushing some of the on-curve points out to attain convexity, this patch pulls all the off curve points in.
R=reed@google.com
Review URL: https://codereview.chromium.org/24810002
git-svn-id: http://skia.googlecode.com/svn/trunk@11504 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/expectations/gm/ignored-tests.txt b/expectations/gm/ignored-tests.txt
index 0cc2bba..93bcb25 100644
--- a/expectations/gm/ignored-tests.txt
+++ b/expectations/gm/ignored-tests.txt
@@ -21,3 +21,15 @@
## Added by edisonn as part of https://codereview.chromium.org/23851037/
#gradients
+# Added by robertphillips as part of https://codereview.chromium.org/24810002/
+shadertext
+shadertext2
+rrect
+rrect_aa
+rrect_clip_aa
+hairlines
+arcofzorro
+convexpaths
+strokerect
+degeneratesegments
+convexpaths
diff --git a/src/core/SkGeometry.cpp b/src/core/SkGeometry.cpp
index 5e77dd3..45658a0 100644
--- a/src/core/SkGeometry.cpp
+++ b/src/core/SkGeometry.cpp
@@ -1205,8 +1205,7 @@
}
/* given a quad-curve and a point (x,y), chop the quad at that point and place
- the new off-curve point and endpoint into 'dest'. The new end point is used
- (rather than (x,y)) to compensate for numerical inaccuracies.
+ the new off-curve point and endpoint into 'dest'.
Should only return false if the computed pos is the start of the curve
(i.e. root == 0)
*/
@@ -1232,7 +1231,7 @@
SkPoint tmp[5];
SkChopQuadAt(quad, tmp, t);
dest[0] = tmp[1];
- dest[1] = tmp[2];
+ dest[1].set(x, y);
return true;
} else {
/* t == 0 means either the value triggered a root outside of [0, 1)
@@ -1260,44 +1259,38 @@
#ifdef SK_SCALAR_IS_FLOAT
// Due to floating point issues (i.e., 1.0f - SK_ScalarRoot2Over2 !=
-// SK_ScalarRoot2Over2 - SK_ScalarTanPIOver8) a cruder root2over2
-// approximation is required to make the quad circle points convex. The
-// root of the problem is that with the root2over2 value in SkScalar.h
-// the arcs really are ever so slightly concave. Some alternative fixes
-// to this problem (besides just arbitrarily pushing out the mid-point as
-// is done here) are:
-// Adjust all the points (not just the middle) to both better approximate
-// the curve and remain convex
-// Switch over to using cubics rather then quads
-// Use a different method to create the mid-point (e.g., compute
-// the two side points, average them, then move it out as needed
-#define SK_ScalarRoot2Over2_QuadCircle 0.7072f
-
+// SK_ScalarRoot2Over2 - SK_ScalarTanPIOver8), the "correct" off curve
+// control points cause the quadratic circle approximation to be concave.
+// SK_OffEps is used to pull in the off-curve control points a bit
+// to make the quadratic approximation convex.
+// Pulling the off-curve controls points in is preferable to pushing some
+// of the on-curve points off.
+#define SK_OffEps 0.0001f
#else
- #define SK_ScalarRoot2Over2_QuadCircle SK_FixedRoot2Over2
+#define SK_OffEps 0
#endif
static const SkPoint gQuadCirclePts[kSkBuildQuadArcStorage] = {
{ SK_Scalar1, 0 },
- { SK_Scalar1, SK_ScalarTanPIOver8 },
- { SK_ScalarRoot2Over2_QuadCircle, SK_ScalarRoot2Over2_QuadCircle },
- { SK_ScalarTanPIOver8, SK_Scalar1 },
+ { SK_Scalar1 - SK_OffEps, SK_ScalarTanPIOver8 - SK_OffEps },
+ { SK_ScalarRoot2Over2, SK_ScalarRoot2Over2 },
+ { SK_ScalarTanPIOver8 - SK_OffEps, SK_Scalar1 - SK_OffEps },
{ 0, SK_Scalar1 },
- { -SK_ScalarTanPIOver8, SK_Scalar1 },
- { -SK_ScalarRoot2Over2_QuadCircle, SK_ScalarRoot2Over2_QuadCircle },
- { -SK_Scalar1, SK_ScalarTanPIOver8 },
+ { -SK_ScalarTanPIOver8 + SK_OffEps,SK_Scalar1 - SK_OffEps },
+ { -SK_ScalarRoot2Over2, SK_ScalarRoot2Over2 },
+ { -SK_Scalar1 + SK_OffEps, SK_ScalarTanPIOver8 - SK_OffEps },
{ -SK_Scalar1, 0 },
- { -SK_Scalar1, -SK_ScalarTanPIOver8 },
- { -SK_ScalarRoot2Over2_QuadCircle, -SK_ScalarRoot2Over2_QuadCircle },
- { -SK_ScalarTanPIOver8, -SK_Scalar1 },
+ { -SK_Scalar1 + SK_OffEps, -SK_ScalarTanPIOver8 + SK_OffEps },
+ { -SK_ScalarRoot2Over2, -SK_ScalarRoot2Over2 },
+ { -SK_ScalarTanPIOver8 + SK_OffEps,-SK_Scalar1 + SK_OffEps },
{ 0, -SK_Scalar1 },
- { SK_ScalarTanPIOver8, -SK_Scalar1 },
- { SK_ScalarRoot2Over2_QuadCircle, -SK_ScalarRoot2Over2_QuadCircle },
- { SK_Scalar1, -SK_ScalarTanPIOver8 },
+ { SK_ScalarTanPIOver8 - SK_OffEps, -SK_Scalar1 + SK_OffEps },
+ { SK_ScalarRoot2Over2, -SK_ScalarRoot2Over2 },
+ { SK_Scalar1 - SK_OffEps, -SK_ScalarTanPIOver8 + SK_OffEps },
{ SK_Scalar1, 0 }
};
diff --git a/src/core/SkPath.cpp b/src/core/SkPath.cpp
index f9a17df..2520467 100644
--- a/src/core/SkPath.cpp
+++ b/src/core/SkPath.cpp
@@ -1230,7 +1230,8 @@
matrix.postTranslate(oval.centerX(), oval.centerY());
return SkBuildQuadArc(start, stop,
- sweepAngle > 0 ? kCW_SkRotationDirection : kCCW_SkRotationDirection,
+ sweepAngle > 0 ? kCW_SkRotationDirection :
+ kCCW_SkRotationDirection,
&matrix, pts);
}