static TransformationMatrix applyTransformAnimation(const TransformOperations& from, const TransformOperations& to, double progress, const FloatSize& boxSize, bool listsMatch)
{
    TransformationMatrix matrix;

    // First frame of an animation.
    if (!progress) {
        from.apply(boxSize, matrix);
        return matrix;
    }

    // Last frame of an animation.
    if (progress == 1) {
        to.apply(boxSize, matrix);
        return matrix;
    }

    // If we have incompatible operation lists, we blend the resulting matrices.
    if (!listsMatch) {
        TransformationMatrix fromMatrix;
        to.apply(boxSize, matrix);
        from.apply(boxSize, fromMatrix);
        matrix.blend(fromMatrix, progress);
        return matrix;
    }

    // Animation to "-webkit-transform: none".
    if (!to.size()) {
        TransformOperations blended(from);
        for (auto& operation : blended.operations())
            operation->blend(nullptr, progress, true)->apply(matrix, boxSize);
        return matrix;
    }

    // Animation from "-webkit-transform: none".
    if (!from.size()) {
        TransformOperations blended(to);
        for (auto& operation : blended.operations())
            operation->blend(nullptr, 1 - progress, true)->apply(matrix, boxSize);
        return matrix;
    }

    // Normal animation with a matching operation list.
    TransformOperations blended(to);
    for (size_t i = 0; i < blended.operations().size(); ++i)
        blended.operations()[i]->blend(from.at(i), progress, !from.at(i))->apply(matrix, boxSize);
    return matrix;
}
void ArgumentCoder<TransformOperations>::encode(ArgumentEncoder& encoder, const TransformOperations& transformOperations)
{
    encoder << static_cast<uint32_t>(transformOperations.size());
    for (size_t i = 0; i < transformOperations.size(); ++i) {
        const TransformOperation* operation = transformOperations.at(i);
        encoder.encodeEnum(operation->getOperationType());

        switch (operation->getOperationType()) {
        case TransformOperation::SCALE_X:
        case TransformOperation::SCALE_Y:
        case TransformOperation::SCALE:
        case TransformOperation::SCALE_Z:
        case TransformOperation::SCALE_3D:
            encoder << static_cast<const ScaleTransformOperation*>(operation)->x();
            encoder << static_cast<const ScaleTransformOperation*>(operation)->y();
            encoder << static_cast<const ScaleTransformOperation*>(operation)->z();
            break;
        case TransformOperation::TRANSLATE_X:
        case TransformOperation::TRANSLATE_Y:
        case TransformOperation::TRANSLATE:
        case TransformOperation::TRANSLATE_Z:
        case TransformOperation::TRANSLATE_3D:
            ArgumentCoder<Length>::encode(encoder, static_cast<const TranslateTransformOperation*>(operation)->x());
            ArgumentCoder<Length>::encode(encoder, static_cast<const TranslateTransformOperation*>(operation)->y());
            ArgumentCoder<Length>::encode(encoder, static_cast<const TranslateTransformOperation*>(operation)->z());
            break;
        case TransformOperation::ROTATE:
        case TransformOperation::ROTATE_X:
        case TransformOperation::ROTATE_Y:
        case TransformOperation::ROTATE_3D:
            encoder << static_cast<const RotateTransformOperation*>(operation)->x();
            encoder << static_cast<const RotateTransformOperation*>(operation)->y();
            encoder << static_cast<const RotateTransformOperation*>(operation)->z();
            encoder << static_cast<const RotateTransformOperation*>(operation)->angle();
            break;
        case TransformOperation::SKEW_X:
        case TransformOperation::SKEW_Y:
        case TransformOperation::SKEW:
            encoder << static_cast<const SkewTransformOperation*>(operation)->angleX();
            encoder << static_cast<const SkewTransformOperation*>(operation)->angleY();
            break;
        case TransformOperation::MATRIX:
            ArgumentCoder<TransformationMatrix>::encode(encoder, static_cast<const MatrixTransformOperation*>(operation)->matrix());
            break;
        case TransformOperation::MATRIX_3D:
            ArgumentCoder<TransformationMatrix>::encode(encoder, static_cast<const Matrix3DTransformOperation*>(operation)->matrix());
            break;
        case TransformOperation::PERSPECTIVE:
            ArgumentCoder<Length>::encode(encoder, static_cast<const PerspectiveTransformOperation*>(operation)->perspective());
            break;
        case TransformOperation::IDENTITY:
            break;
        case TransformOperation::NONE:
            ASSERT_NOT_REACHED();
            break;
        }
    }
}
void PrintTo(const AnimatableTransform& animTransform, ::std::ostream* os)
{
    TransformOperations ops = animTransform.transformOperations();

    *os << "AnimatableTransform(";
    // FIXME: TransformOperations should really have it's own pretty-printer
    // then we could just call that.
    // FIXME: Output useful names not just the raw matrixes.
    for (unsigned i = 0; i < ops.size(); i++) {
        const TransformOperation* op = ops.at(i);

        TransformationMatrix matrix;
        op->apply(matrix, FloatSize(1.0, 1.0));

        *os << "[";
        if (matrix.isAffine()) {
            *os << matrix.a();
            *os << " " << matrix.b();
            *os << " " << matrix.c();
            *os << " " << matrix.d();
            *os << " " << matrix.e();
            *os << " " << matrix.f();
        } else {
            *os << matrix.m11();
            *os << " " << matrix.m12();
            *os << " " << matrix.m13();
            *os << " " << matrix.m14();
            *os << " ";
            *os << " " << matrix.m21();
            *os << " " << matrix.m22();
            *os << " " << matrix.m23();
            *os << " " << matrix.m24();
            *os << " ";
            *os << " " << matrix.m31();
            *os << " " << matrix.m32();
            *os << " " << matrix.m33();
            *os << " " << matrix.m34();
            *os << " ";
            *os << " " << matrix.m41();
            *os << " " << matrix.m42();
            *os << " " << matrix.m43();
            *os << " " << matrix.m44();
        }
        *os << "]";
        if (i < ops.size() - 1)
            *os << ", ";
    }
    *os << ")";
}