interpret conic tolerance correctly -- big rebaseline

src/core/SkGeometry.cpp

Index: src/core/SkGeometry.cpp
diff --git a/src/core/SkGeometry.cpp b/src/core/SkGeometry.cpp
index 0246081735b7f6a88756769c17673729e154518a..5b9c50138a2e6e9c8db0d8569f6ef2230418d0d0 100644
--- a/src/core/SkGeometry.cpp
+++ b/src/core/SkGeometry.cpp
@@ -1439,8 +1439,17 @@ bool SkConic::asQuadTol(SkScalar tol) const {
     return (x * x + y * y) <= tol * tol;
 }
 

[robertphillips, 2015/02/11 20:01:09]

suggested?

+// Limit the number of suggested quads to approximate a conic
+#define kMaxConicToQuadPOW2 4
+
 int SkConic::computeQuadPOW2(SkScalar tol) const {
+    if (tol < 0 || !SkScalarIsFinite(tol)) {
+        return 0;
+    }
+
     AS_QUAD_ERROR_SETUP
+

[robertphillips, 2015/02/11 20:01:54]

Don't you want to put this in a gypi somewhere?

+#ifdef SK_SUPPORT_LEGACY_CONIC_COMPUTE_QUAD_POW2
     SkScalar error = SkScalarSqrt(x * x + y * y) - tol;
 
     if (error <= 0) {
@@ -1448,6 +1457,17 @@ int SkConic::computeQuadPOW2(SkScalar tol) const {
     }
     uint32_t ierr = (uint32_t)error;
     return (34 - SkCLZ(ierr)) >> 1;
+#else
+    SkScalar error = SkScalarSqrt(x * x + y * y);
+    int pow2;
+    for (pow2 = 0; pow2 < kMaxConicToQuadPOW2; ++pow2) {
+        if (error <= tol) {
+            break;
+        }
+        error *= 0.25f;
+    }
+    return pow2;
+#endif
 }
 
 static SkPoint* subdivide(const SkConic& src, SkPoint pts[], int level) {