3 files changed, 30 insertions, 19 deletions

diff --git a/src/core/SkDraw.cpp b/src/core/SkDraw.cpp
index 77af440caf..70cb485f73 100644
--- a/src/core/SkDraw.cpp
+++ b/src/core/SkDraw.cpp
@@ -380,36 +380,35 @@ bool PtProcRec::init(SkCanvas::PointMode mode, const SkPaint& paint,
     if ((unsigned)mode > (unsigned)SkCanvas::kPolygon_PointMode) {
         return false;
     }
-
     if (paint.getPathEffect()) {
         return false;
     }
     SkScalar width = paint.getStrokeWidth();
+    SkScalar radius = -1;   // sentinel value, a "valid" value must be > 0
+
     if (0 == width) {
+        radius = 0.5f;
+    } else if (paint.getStrokeCap() != SkPaint::kRound_Cap &&
+               matrix->isScaleTranslate() && SkCanvas::kPoints_PointMode == mode) {
+        SkScalar sx = matrix->get(SkMatrix::kMScaleX);
+        SkScalar sy = matrix->get(SkMatrix::kMScaleY);
+        if (SkScalarNearlyZero(sx - sy)) {
+            radius = SkScalarHalf(width * SkScalarAbs(sx));
+        }
+    }
+    if (radius > 0) {
+        // if we return true, the caller may assume that the constructed shapes can be represented
+        // using SkFixed, so we preflight that here, looking at the radius and clip-bounds
+        if (!SkRectPriv::FitsInFixed(SkRect::Make(rc->getBounds()).makeOutset(radius, radius))) {
+            return false;
+        }
         fMode = mode;
         fPaint = &paint;
         fClip = nullptr;
         fRC = rc;
-        fRadius = SK_FixedHalf;
+        fRadius = SkScalarToFixed(radius);
         return true;
     }
-    if (paint.getStrokeCap() != SkPaint::kRound_Cap &&
-        matrix->isScaleTranslate() && SkCanvas::kPoints_PointMode == mode) {
-        SkScalar sx = matrix->get(SkMatrix::kMScaleX);
-        SkScalar sy = matrix->get(SkMatrix::kMScaleY);
-        if (SkScalarNearlyZero(sx - sy)) {
-            if (sx < 0) {
-                sx = -sx;
-            }
-
-            fMode = mode;
-            fPaint = &paint;
-            fClip = nullptr;
-            fRC = rc;
-            fRadius = SkScalarToFixed(width * sx) >> 1;
-            return true;
-        }
-    }
     return false;
 }
 
diff --git a/src/core/SkMathPriv.h b/src/core/SkMathPriv.h
index 6c33e36747..dcdd81fd41 100644
--- a/src/core/SkMathPriv.h
+++ b/src/core/SkMathPriv.h
@@ -215,4 +215,9 @@ static inline size_t GrNextSizePow2(size_t n) {
     return n + 1;
 }
 
+// conservative check. will return false for very large values that "could" fit
+template <typename T> static inline bool SkFitsInFixed(T x) {
+    return SkTAbs(x) <= 32767.0f;
+}
+
 #endif
diff --git a/src/core/SkRectPriv.h b/src/core/SkRectPriv.h
index 16c9535cc8..d2a2ce4665 100644
--- a/src/core/SkRectPriv.h
+++ b/src/core/SkRectPriv.h
@@ -9,6 +9,7 @@
 #define SkRectPriv_DEFINED
 
 #include "SkRect.h"
+#include "SkMathPriv.h"
 
 class SkRectPriv {
 public:
@@ -45,6 +46,12 @@ public:
         r->fTop    = SkMinScalar(pt.fY, r->fTop);
         r->fBottom = SkMaxScalar(pt.fY, r->fBottom);
     }
+
+    // conservative check. will return false for very large values that "could" fit
+    static bool FitsInFixed(const SkRect& r) {
+        return SkFitsInFixed(r.fLeft) && SkFitsInFixed(r.fTop) &&
+               SkFitsInFixed(r.fRight) && SkFitsInFixed(r.fBottom);
+    }
 };