Adding Blink-side 3d Box and Bounds calculations to TransformOperations

Source/platform/transforms/RotateTransformOperation.cpp

Index: Source/platform/transforms/RotateTransformOperation.cpp
diff --git a/Source/platform/transforms/RotateTransformOperation.cpp b/Source/platform/transforms/RotateTransformOperation.cpp
index 94ab0d431f5be5ec2bcb002444378bc5d9ad49c0..9c9d95d883392b72327b18697206cb58c20ca201 100644
--- a/Source/platform/transforms/RotateTransformOperation.cpp
+++ b/Source/platform/transforms/RotateTransformOperation.cpp
@@ -30,6 +30,63 @@ using namespace std;
 
 namespace WebCore {
 
+const double kAngleEpsilon = 1e-4;
+
+static bool isZeroAxis(const RotateTransformOperation& from)

[Ian Vollick, 2014/06/16 15:23:37]

Please expose this rather than duplicating in TransformOperations.cpp.
RotateTransformOperation::hasZeroLengthAxis or something.

[awoloszyn, 2014/06/17 14:26:01]

Done.

+{
+    double length = from.x() * from.x() + from.y() * from.y() + from.z() * from.z();

[Ian Vollick, 2014/06/16 15:23:37]

If you add a FloatPoint3D RotationTransformOperations::axis() fn, you can use
FloatPoint3D's lengthSquared here (as well as its 'dot' later).

[awoloszyn, 2014/06/17 14:26:00]

Done.

+    return(length < kAngleEpsilon);
+}
+
+static bool shareSameAxis(const RotateTransformOperation* from, const RotateTransformOperation* to, double& x, double& y, double& z, double& fromAngle, double& toAngle)

[Ian Vollick, 2014/06/16 15:23:37]

Please expose this, too.

[awoloszyn, 2014/06/17 14:26:00]

Done.

+{
+    x = 0;
+    y = 0;
+    z = 1;
+    fromAngle = 0;
+    toAngle = 0;
+
+    if (!from && !to)
+        return true;
+
+    bool fromZero = !from || isZeroAxis(*from);
+    bool toZero = !to || isZeroAxis(*to);
+
+    if (fromZero && toZero)
+        return true;
+
+    if (fromZero) {
+        x = to->x();
+        y = to->y();
+        z = to->z();
+        toAngle = to->angle();
+        return true;
+    }
+
+    if (toZero) {
+        x = from->x();
+        y = from->y();
+        z = from->z();
+        fromAngle = from->angle();
+        return true;
+    }
+
+    double fromSquared = from->x() * from->x() + from->y() * from->y() + from->z() * from->z();
+    double toSquared   = to->x()   * to->x()   + to->y()   * to->y()   + to->z()   * to->z();
+
+    double dot = from->x() * to->x() + from->y() * to->y() + from->z() * to->z();
+    double error = std::abs(1 - (dot * dot) / (fromSquared * toSquared));
+
+    if (error > kAngleEpsilon)
+        return false;
+    x = from->x();
+    y = from->y();
+    z = from->z();
+    fromAngle = from->angle();
+    toAngle = to->angle();
+    return true;
+}
+
 PassRefPtr<TransformOperation> RotateTransformOperation::blend(const TransformOperation* from, double progress, bool blendToIdentity)
 {
     if (from && !from->isSameType(*this))
@@ -50,6 +107,14 @@ PassRefPtr<TransformOperation> RotateTransformOperation::blend(const TransformOp
                                                 fromOp ? fromOp->m_z : m_z,
                                                 WebCore::blend(fromAngle, m_angle, progress), m_type);
     }
+    double axisX;
+    double axisY;
+    double axisZ;
+    double fromAngle;
+    double toAngle;
+    if (shareSameAxis(fromOp, this, axisX, axisY, axisZ, fromAngle, toAngle)) {
+        return RotateTransformOperation::create(axisX, axisY, axisZ, WebCore::blend(fromAngle, toAngle, progress), m_type);
+    }
 
     const RotateTransformOperation* toOp = this;
 
@@ -93,4 +158,9 @@ PassRefPtr<TransformOperation> RotateTransformOperation::blend(const TransformOp
     return RotateTransformOperation::create(x, y, z, angle, Rotate3D);
 }
 
+bool RotateTransformOperation::isCompatibleType(const TransformOperation& other) const
+{
+    return(other.isSameType(*this));
+}
+
 } // namespace WebCore