Add gfx::Transform::TransformBox and TransformBoxReverse

ui/gfx/transform.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // MSVC++ requires this to be set before any other includes to get M_PI.
 #define _USE_MATH_DEFINES
 
 #include "ui/gfx/transform.h"
 
 #include <cmath>
 
 #include "base/logging.h"
 #include "base/strings/stringprintf.h"
+#include "ui/gfx/box_f.h"
 #include "ui/gfx/point.h"
 #include "ui/gfx/point3_f.h"
 #include "ui/gfx/rect.h"
 #include "ui/gfx/safe_integer_conversions.h"
 #include "ui/gfx/skia_util.h"
 #include "ui/gfx/transform_util.h"
 #include "ui/gfx/vector3d_f.h"
 
 namespace gfx {
 
@@ skipping 397 matching lines @@
   if (!matrix_.invert(&inverse))
     return false;
 
   const SkMatrix& matrix = inverse;
   SkRect src = RectFToSkRect(*rect);
   matrix.mapRect(&src);
   *rect = SkRectToRectF(src);
   return true;
 }
 
+void Transform::TransformBox(BoxF* box) const {
+  BoxF bounds;
+  bool first_point = true;
+  for (int corner = 0; corner < 8; ++corner) {
+    gfx::Point3F point = box->origin();
+    point += gfx::Vector3dF(corner & 1 ? box->width() : 0.f,
+                            corner & 2 ? box->height() : 0.f,
+                            corner & 4 ? box->depth() : 0.f);
+    TransformPoint(&point);
+    if (first_point) {
+      bounds.set_origin(point);
+      first_point = false;
+    } else {
+      bounds.ExpandTo(point);
+    }
+  }
+  *box = bounds;
+}
+
+bool Transform::TransformBoxReverse(BoxF* box) const {
+  gfx::Transform inverse = *this;
+  if (!GetInverse(&inverse))
+    return false;
+  inverse.TransformBox(box);
+  return true;
+}
+
 bool Transform::Blend(const Transform& from, double progress) {
   DecomposedTransform to_decomp;
   DecomposedTransform from_decomp;
   if (!DecomposeTransform(&to_decomp, *this) ||
       !DecomposeTransform(&from_decomp, from))
     return false;
 
   if (!BlendDecomposedTransforms(&to_decomp, to_decomp, from_decomp, progress))
     return false;
 
@@ skipping 49 matching lines @@
       matrix_.get(2, 1),
       matrix_.get(2, 2),
       matrix_.get(2, 3),
       matrix_.get(3, 0),
       matrix_.get(3, 1),
       matrix_.get(3, 2),
       matrix_.get(3, 3));
 }
 
 }  // namespace gfx