diff --git a/gm/gm.cpp b/gm/gm.cpp
index cf4b640..f9c0e66 100644
--- a/gm/gm.cpp
+++ b/gm/gm.cpp
@@ -41,5 +41,14 @@
     canvas->drawColor(fBGColor);
 }
 
+void GM::drawSizeBounds(SkCanvas* canvas, SkColor color) {
+    SkISize size = this->getISize();
+    SkRect r = SkRect::MakeWH(SkIntToScalar(size.width()),
+                              SkIntToScalar(size.height()));
+    SkPaint paint;
+    paint.setColor(color);
+    canvas->drawRect(r, paint);
+}
+
 // need to explicitly declare this, or we get some weird infinite loop llist
 template GMRegistry* SkTRegistry<GM*, void*>::gHead;
diff --git a/gm/gm.h b/gm/gm.h
index 21366aa..b0de922 100644
--- a/gm/gm.h
+++ b/gm/gm.h
@@ -49,6 +49,10 @@
         SkColor getBGColor() const { return fBGColor; }
         void setBGColor(SkColor);
 
+        // helper: fill a rect in the specified color based on the
+        // GM's getISize bounds.
+        void drawSizeBounds(SkCanvas*, SkColor);
+
 	protected:
 		virtual void onDraw(SkCanvas*) = 0;
 		virtual void onDrawBackground(SkCanvas*);