saturate IPoint math, handle NaN in isEmpty

Bug: skia:7507
Change-Id: Ibdb40584effdea70e6499eab1bb64bb4b2260d06
Reviewed-on: https://skia-review.googlesource.com/106972
Commit-Queue: Mike Reed <reed@google.com>
Commit-Queue: Mike Klein <mtklein@chromium.org>
Reviewed-by: Mike Klein <mtklein@chromium.org>

1 files changed, 12 insertions, 6 deletions

diff --git a/include/core/SkRect.h b/include/core/SkRect.h
index 5673980d49..ff7715853a 100644
--- a/include/core/SkRect.h
+++ b/include/core/SkRect.h
@@ -849,12 +849,18 @@ struct SK_API SkRect {
     }
 
     /** Returns true if fLeft is equal to or greater than fRight, or if fTop is equal
-        to or greater than fBottom. Call sort() to reverse rectangles with negative
-        width() or height().
-
-        @return  true if width() or height() are zero or negative
-    */
-    bool isEmpty() const { return fLeft >= fRight || fTop >= fBottom; }
+     *  to or greater than fBottom. Call sort() to reverse rectangles with negative
+     *  width() or height().
+     *
+     *  This function also returns true if any of the values are NaN.
+     *
+     *  @return  true if width() or height() are zero or negative
+     */
+    bool isEmpty() const {
+        // We write it as the NOT of a non-empty rect, so we will return true if any values
+        // are NaN.
+        return !(fLeft < fRight && fTop < fBottom);
+    }
 
     /** Returns true if fLeft is equal to or less than fRight, or if fTop is equal
         to or less than fBottom. Call sort() to reverse rectangles with negative