Type conversion fixes, ui/gfx/ edition.

ui/gfx/geometry/rect.h

Index: ui/gfx/geometry/rect.h
diff --git a/ui/gfx/geometry/rect.h b/ui/gfx/geometry/rect.h
index fed202d2bd30b769f91ee041c70224f618495010..53d43ef55186a157e8096f914a8fe7b85946d6ea 100644
--- a/ui/gfx/geometry/rect.h
+++ b/ui/gfx/geometry/rect.h
@@ -18,6 +18,7 @@
 
 #include "ui/gfx/geometry/point.h"
 #include "ui/gfx/geometry/rect_f.h"
+#include "ui/gfx/geometry/safe_integer_conversions.h"
 #include "ui/gfx/geometry/size.h"
 #include "ui/gfx/geometry/vector2d.h"
 
@@ -59,7 +60,8 @@ class GFX_EXPORT Rect {
 #endif
 
   operator RectF() const {
-    return RectF(origin().x(), origin().y(), size().width(), size().height());
+    return RectF(static_cast<float>(x()), static_cast<float>(y()),
+                 static_cast<float>(width()), static_cast<float>(height()));
   }
 
   int x() const { return origin_.x(); }
@@ -220,10 +222,10 @@ GFX_EXPORT Rect BoundingRect(const Point& p1, const Point& p2);
 inline Rect ScaleToEnclosingRect(const Rect& rect,
                                  float x_scale,
                                  float y_scale) {
-  int x = std::floor(rect.x() * x_scale);
-  int y = std::floor(rect.y() * y_scale);
-  int r = rect.width() == 0 ? x : std::ceil(rect.right() * x_scale);
-  int b = rect.height() == 0 ? y : std::ceil(rect.bottom() * y_scale);
+  int x = ToFlooredInt(rect.x() * x_scale);

[danakj, 2014/10/23 15:35:44]

i had written these purposefully as static_casts instead of ToFloored/CeiledInt
because those functions do clamping stuff to make sure the result fits in an
int, whereas this method is going from int inputs to int outputs, so I wanted to
rely on the caller making sure things fit instead.

[Peter Kasting, 2014/10/23 17:29:45]

Is that a performance concern?  I originally added casts in here but it made the
code harder to read due to introducing line-wrapping; using these helpers is
very clear.  If you're worried only about clarity, we could simply add a comment
in these functions noting that the clamping portion of the helpers is
unnecessary.  If this is a performance problem, then we can probably cast and
note that it's impossible for the code to need clamping due to the source values
being integral.

[danakj, 2014/10/23 17:43:23]

I think we should cast unless we can show there is no negative performance
change by using the helpers. The testing methodology I used in
https://code.google.com/p/chromium/issues/detail?id=407444 would be appropriate
here too if you want to do that.

+  int y = ToFlooredInt(rect.y() * y_scale);
+  int r = rect.width() == 0 ? x : ToCeiledInt(rect.right() * x_scale);
+  int b = rect.height() == 0 ? y : ToCeiledInt(rect.bottom() * y_scale);
   return Rect(x, y, r - x, b - y);
 }
 
@@ -234,10 +236,10 @@ inline Rect ScaleToEnclosingRect(const Rect& rect, float scale) {
 inline Rect ScaleToEnclosedRect(const Rect& rect,
                                 float x_scale,
                                 float y_scale) {
-  int x = std::ceil(rect.x() * x_scale);
-  int y = std::ceil(rect.y() * y_scale);
-  int r = rect.width() == 0 ? x : std::floor(rect.right() * x_scale);
-  int b = rect.height() == 0 ? y : std::floor(rect.bottom() * y_scale);
+  int x = ToCeiledInt(rect.x() * x_scale);
+  int y = ToCeiledInt(rect.y() * y_scale);
+  int r = rect.width() == 0 ? x : ToFlooredInt(rect.right() * x_scale);
+  int b = rect.height() == 0 ? y : ToFlooredInt(rect.bottom() * y_scale);
   return Rect(x, y, r - x, b - y);
 }