Use Skia's mapMScalars() for mapping homogeneous points.

Skia provides a point mapping method, so we don't need to roll
our own.  This deletes some unnecessary code and with any luck compiles
to faster code.

NOTRY=true
BUG=none

Review URL: https://chromiumcodereview.appspot.com/21161004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@214719 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 23 insertions, 17 deletions

diff --git a/cc/base/math_util.h b/cc/base/math_util.h
index cb158dd..23eb20f 100644
--- a/cc/base/math_util.h
+++ b/cc/base/math_util.h
@@ -29,37 +29,43 @@ class Vector2dF;
 namespace cc {
 
 struct HomogeneousCoordinate {
-  HomogeneousCoordinate(double new_x, double new_y, double new_z, double new_w)
-      : x(new_x), y(new_y), z(new_z), w(new_w) {}
+  HomogeneousCoordinate(SkMScalar x, SkMScalar y, SkMScalar z, SkMScalar w) {
+    vec[0] = x;
+    vec[1] = y;
+    vec[2] = z;
+    vec[3] = w;
+  }
 
-  bool ShouldBeClipped() const { return w <= 0.0; }
+  bool ShouldBeClipped() const { return w() <= 0.0; }
 
   gfx::PointF CartesianPoint2d() const {
-    if (w == 1.0)
-      return gfx::PointF(x, y);
+    if (w() == 1.0)
+      return gfx::PointF(x(), y());
 
     // For now, because this code is used privately only by MathUtil, it should
     // never be called when w == 0, and we do not yet need to handle that case.
-    DCHECK(w);
-    double inv_w = 1.0 / w;
-    return gfx::PointF(x * inv_w, y * inv_w);
+    DCHECK(w());
+    double inv_w = 1.0 / w();
+    return gfx::PointF(x() * inv_w, y() * inv_w);
   }
 
   gfx::Point3F CartesianPoint3d() const {
-    if (w == 1)
-      return gfx::Point3F(x, y, z);
+    if (w() == 1)
+      return gfx::Point3F(x(), y(), z());
 
     // For now, because this code is used privately only by MathUtil, it should
     // never be called when w == 0, and we do not yet need to handle that case.
-    DCHECK(w);
-    double inv_w = 1.0 / w;
-    return gfx::Point3F(x * inv_w, y * inv_w, z * inv_w);
+    DCHECK(w());
+    double inv_w = 1.0 / w();
+    return gfx::Point3F(x() * inv_w, y() * inv_w, z() * inv_w);
   }
 
-  double x;
-  double y;
-  double z;
-  double w;
+  SkMScalar x() const { return vec[0]; }
+  SkMScalar y() const { return vec[1]; }
+  SkMScalar z() const { return vec[2]; }
+  SkMScalar w() const { return vec[3]; }
+
+  SkMScalar vec[4];
 };
 
 class CC_EXPORT MathUtil {