activation-base.hpp

// BSD 3-Clause License
//
// Copyright (C) 2019-2025, LAAS-CNRS, University of Edinburgh,
// Heriot-Watt University
// Copyright note valid unless otherwise stated in individual files.
// All rights reserved.

#ifndef CROCODDYL_CORE_ACTIVATION_BASE_HPP_
#define CROCODDYL_CORE_ACTIVATION_BASE_HPP_

#include "crocoddyl/core/fwd.hpp"

namespace crocoddyl {

class ActivationModelBase {
 public:
 virtual ~ActivationModelBase() = default;

 CROCODDYL_BASE_CAST(ActivationModelBase, ActivationModelAbstractTpl)
};

template <typename _Scalar>
class ActivationModelAbstractTpl : public ActivationModelBase {
 public:
 EIGEN_MAKE_ALIGNED_OPERATOR_NEW

 typedef _Scalar Scalar;
 typedef MathBaseTpl<Scalar> MathBase;
 typedef ActivationDataAbstractTpl<Scalar> ActivationDataAbstract;
 typedef typename MathBase::VectorXs VectorXs;
 typedef typename MathBase::MatrixXs MatrixXs;

 explicit ActivationModelAbstractTpl(const std::size_t nr) : nr_(nr) {};
 virtual ~ActivationModelAbstractTpl() = default;

 virtual void calc(const std::shared_ptr<ActivationDataAbstract>& data,
 const Eigen::Ref<const VectorXs>& r) = 0;
 virtual void calcDiff(const std::shared_ptr<ActivationDataAbstract>& data,
 const Eigen::Ref<const VectorXs>& r) = 0;
 virtual std::shared_ptr<ActivationDataAbstract> createData() {
 return std::allocate_shared<ActivationDataAbstract>(
 Eigen::aligned_allocator<ActivationDataAbstract>(), this);
 };

 std::size_t get_nr() const { return nr_; };

 friend std::ostream& operator<<(
 std::ostream& os, const ActivationModelAbstractTpl<Scalar>& model) {
 model.print(os);
 return os;
 }

 virtual void print(std::ostream& os) const {
 os << boost::core::demangle(typeid(*this).name());
 }

 protected:
 std::size_t nr_;
 ActivationModelAbstractTpl() : nr_(0) {};
};

template <typename _Scalar>
struct ActivationDataAbstractTpl {
 EIGEN_MAKE_ALIGNED_OPERATOR_NEW

 typedef _Scalar Scalar;
 typedef MathBaseTpl<Scalar> MathBase;
 typedef typename MathBase::VectorXs VectorXs;
 typedef typename MathBase::MatrixXs MatrixXs;
 typedef typename MathBase::DiagonalMatrixXs DiagonalMatrixXs;

 template <template <typename Scalar> class Activation>
 explicit ActivationDataAbstractTpl(Activation<Scalar>* const activation)
 : a_value(Scalar(0.)),
 Ar(VectorXs::Zero(activation->get_nr())),
 Arr(DiagonalMatrixXs(activation->get_nr())) {
 Arr.setZero();
 }
 virtual ~ActivationDataAbstractTpl() = default;

 Scalar a_value;
 VectorXs Ar;
 DiagonalMatrixXs Arr;

 static MatrixXs getHessianMatrix(
 const ActivationDataAbstractTpl<Scalar>& data) {
 return data.Arr.diagonal().asDiagonal();
 }
 static void setHessianMatrix(ActivationDataAbstractTpl<Scalar>& data,
 const MatrixXs& Arr) {
 data.Arr.diagonal() = Arr.diagonal();
 }
};

} // namespace crocoddyl

CROCODDYL_DECLARE_EXTERN_TEMPLATE_CLASS(crocoddyl::ActivationModelAbstractTpl)
CROCODDYL_DECLARE_EXTERN_TEMPLATE_STRUCT(crocoddyl::ActivationDataAbstractTpl)

#endif // CROCODDYL_CORE_ACTIVATION_BASE_HPP_