Add Surface Indication With CK/SYCL? Feature to SPHinXsys

src/shared/shared_ck/particle_dynamics/general_dynamics/all_general_dynamics_ck.h

@@ -35,3 +35,4 @@
 #include "geometric_dynamics.hpp"
 #include "interpolation_dynamics.hpp"
 #include "kernel_correction_ck.hpp"
+#include "all_surface_indication_ck.h"

src/shared/shared_ck/particle_dynamics/general_dynamics/surface_indication/all_surface_indication_ck.h

@@ -0,0 +1,37 @@
+/* ------------------------------------------------------------------------- *
+ *                                SPHinXsys                                  *
+ * ------------------------------------------------------------------------- *
+ * SPHinXsys (pronunciation: s'finksis) is an acronym from Smoothed Particle *
+ * Hydrodynamics for industrial compleX systems. It provides C++ APIs for    *
+ * physical accurate simulation and aims to model coupled industrial dynamic *
+ * systems including fluid, solid, multi-body dynamics and beyond with SPH   *
+ * (smoothed particle hydrodynamics), a meshless computational method using  *
+ * particle discretization.                                                  *
+ *                                                                           *
+ * SPHinXsys is partially funded by German Research Foundation               *
+ * (Deutsche Forschungsgemeinschaft) DFG HU1527/6-1, HU1527/10-1,            *
+ *  HU1527/12-1 and HU1527/12-4.                                             *
+ *                                                                           *
+ * Portions copyright (c) 2017-2023 Technical University of Munich and       *
+ * the authors' affiliations.                                                *
+ *                                                                           *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may   *
+ * not use this file except in compliance with the License. You may obtain a *
+ * copy of the License at http://www.apache.org/licenses/LICENSE-2.0.        *
+ *                                                                           *
+ * ------------------------------------------------------------------------- */
+
+#ifndef B9F4AD2C_8E17_4C49_BCAA_4BD2C6A6951F
+#define B9F4AD2C_8E17_4C49_BCAA_4BD2C6A6951F
+/**
+ * @file    all_general_dynamics.h
+ * @brief   This is the header file that user code should include to pick up all
+ *          general dynamics used in SPHinXsys.
+ * @author	Chi Zhang and Xiangyu Hu
+ */
+
+
+#include "surface_indication_ck.hpp"
+
+
+#endif /* B9F4AD2C_8E17_4C49_BCAA_4BD2C6A6951F */

src/shared/shared_ck/particle_dynamics/general_dynamics/surface_indication/surface_indication_ck.h

@@ -0,0 +1,183 @@
+#ifndef SURFACE_INDICATION_CK_H
+#define SURFACE_INDICATION_CK_H
+
+#include "base_general_dynamics.h"
+#include "base_fluid_dynamics.h"
+#include "interaction_ck.hpp"
+
+namespace SPH
+{
+namespace fluid_dynamics
+{
+/**
+ * @class FreeSurfaceIndicationCK
+ * @brief Free-surface indication with configurable relationship types.
+ * 
+ * This template is specialized for different combinations of
+ * "Base" + "Inner" / "Contact" relations to handle free-surface
+ * detection and updating in SPH simulations.
+ */
+template <typename... RelationTypes>
+class FreeSurfaceIndicationCK;
+
+//=================================================================================================//
+// Base relation version
+//=================================================================================================//
+/**
+ * @class FreeSurfaceIndicationCK<Base, RelationType<Parameters...>>
+ * @brief Basic free-surface indication logic, storing and computing
+ *        positional divergence, surface indicators, etc.
+ */
+template <template <typename...> class RelationType, typename... Parameters>
+class FreeSurfaceIndicationCK<Base, RelationType<Parameters...>>
+    : public Interaction<RelationType<Parameters...>>
+{
+public:
+    template <class BaseRelationType>
+    explicit FreeSurfaceIndicationCK(BaseRelationType &base_relation);
+    virtual ~FreeSurfaceIndicationCK() {}
+
+    //------------------------------------------------------------------------------------------//
+    /**
+     * @class InteractKernel
+     * @brief Base interaction kernel that calculates positional divergence,
+     *        used in detecting free-surface particles.
+     */
+    class InteractKernel : public Interaction<RelationType<Parameters...>>::InteractKernel
+    {
+    public:
+        template <class ExecutionPolicy, typename... Args>
+        InteractKernel(const ExecutionPolicy &ex_policy,
+                       FreeSurfaceIndicationCK<Base, RelationType<Parameters...>> &encloser,
+                       Args &&...args);
+
+        void interact(size_t index_i, Real dt = 0.0);
+
+    protected:
+        int *indicator_;
+        Real *pos_div_;
+        Real *Vol_;
+        Real threshold_by_dimensions_;
+        Real smoothing_length_;
+    };
+
+protected:
+    DiscreteVariable<int> *dv_indicator_;
+    DiscreteVariable<Real> *dv_pos_div_;
+    DiscreteVariable<Real> *dv_Vol_;
+    Real dv_threshold_by_dimensions_;
+    Real dv_smoothing_length_;
+};
+
+//=================================================================================================//
+// Inner relation version with "WithUpdate"
+//=================================================================================================//
+/**
+ * @class FreeSurfaceIndicationCK<Inner<WithUpdate, FlowType, Parameters...>>
+ * @brief Extends the base free-surface indication for inner relations that also require
+ *        an updating step (e.g., "WithUpdate").
+ */
+template <class FlowType, typename... Parameters>
+class FreeSurfaceIndicationCK<Inner<WithUpdate, FlowType, Parameters...>>
+    : public FreeSurfaceIndicationCK<Base, Inner<Parameters...>>
+{
+public:
+    explicit FreeSurfaceIndicationCK(Relation<Inner<Parameters...>> &inner_relation);
+    virtual ~FreeSurfaceIndicationCK() {}
+
+    //------------------------------------------------------------------------------------------//
+    /**
+     * @class InteractKernel
+     * @brief Interaction kernel for detecting free surface in an inner relation.
+     */
+    class InteractKernel
+        : public FreeSurfaceIndicationCK<Base, Inner<Parameters...>>::InteractKernel
+    {
+    public:
+        template <class ExecutionPolicy>
+        InteractKernel(const ExecutionPolicy &ex_policy,
+                       FreeSurfaceIndicationCK<Inner<WithUpdate, FlowType, Parameters...>> &encloser);
+
+        void interact(size_t index_i, Real dt = 0.0);
+
+        /// Pointer to the previously stored surface indicator.
+        int *previous_surface_indicator_;
+    };
+
+    //------------------------------------------------------------------------------------------//
+    /**
+     * @class UpdateKernel
+     * @brief Post-processing/update kernel that modifies the surface indicator
+     *        based on the newly computed positional divergences and neighbor information.
+     */
+    class UpdateKernel
+        : public FreeSurfaceIndicationCK<Base, Inner<Parameters...>>::InteractKernel
+    {
+    public:
+        template <class ExecutionPolicy>
+        UpdateKernel(const ExecutionPolicy &ex_policy,
+                     FreeSurfaceIndicationCK<Inner<WithUpdate, FlowType, Parameters...>> &encloser);
+
+        void update(size_t index_i, Real dt = 0.0);
+
+    protected:
+        int *previous_surface_indicator_;
+        FreeSurfaceIndicationCK<Inner<WithUpdate, FlowType, Parameters...>> *outer_;
+    };
+
+protected:
+    DiscreteVariable<int> *dv_previous_surface_indicator_;
+};
+
+//------------------------------------------------------------------------------------------//
+// Common type alias for internal flow with free-surface indication (with update).
+using FreeSurfaceIndicationInnerCK = FreeSurfaceIndicationCK<Inner<WithUpdate, Internal>>;
+
+//=================================================================================================//
+// Contact relation version
+//=================================================================================================//
+/**
+ * @class FreeSurfaceIndicationCK<Contact<Parameters...>>
+ * @brief Extends the base free-surface indication for contact relations.
+ */
+template <typename... Parameters>
+class FreeSurfaceIndicationCK<Contact<Parameters...>>
+    : public FreeSurfaceIndicationCK<Base, Contact<Parameters...>>
+{
+public:
+    explicit FreeSurfaceIndicationCK(Relation<Contact<Parameters...>> &contact_relation);
+    virtual ~FreeSurfaceIndicationCK() {}
+
+    //------------------------------------------------------------------------------------------//
+    /**
+     * @class InteractKernel
+     * @brief Interaction kernel for a contact relation, combining data from multiple contact bodies.
+     */
+    class InteractKernel
+        : public FreeSurfaceIndicationCK<Base, Contact<Parameters...>>::InteractKernel
+    {
+    public:
+        template <class ExecutionPolicy>
+        InteractKernel(const ExecutionPolicy &ex_policy,
+                       FreeSurfaceIndicationCK<Contact<Parameters...>> &encloser,
+                       size_t contact_index);
+
+        void interact(size_t index_i, Real dt = 0.0);
+
+    protected:
+        Real *contact_Vol_;
+    };
+
+protected:
+    StdVec<DiscreteVariable<Real> *> dv_contact_Vol_;
+};
+
+//------------------------------------------------------------------------------------------//
+// Common type alias for complex free-surface indication (inner + contact).
+using FreeSurfaceIndicationComplexCK = FreeSurfaceIndicationCK<Inner<WithUpdate, Internal>, Contact<>>;
+//------------------------------------------------------------------------------------------//
+
+} // namespace fluid_dynamics
+} // namespace SPH
+
+#endif // SURFACE_INDICATION_CK_H