Update hydro APIs for added-mass fix and VSG visualization

Author: dav-og

include/hydroc/waves/irregular_wave.h

@@ -51,6 +51,15 @@ class IrregularWaves : public WaveBase {
     Eigen::Vector3d GetVelocity(const Eigen::Vector3d& position, double time, double elevation) override;
     Eigen::Vector3d GetAcceleration(const Eigen::Vector3d& position, double time, double elevation) override;
 
+    /// Return the surface slope (∂η/∂x, ∂η/∂y) at a given position and time.
+    /// Used for computing surface normals in visualization.
+    Eigen::Vector2d GetElevationGradientXY(const Eigen::Vector3d& position, double time) const;
+
+    /// Compute elevation using only the first max_components wave components.
+    /// Used for faster visualization rendering when full accuracy is not required.
+    /// @param max_components Maximum number of frequency components to use (0 or negative = use all)
+    double GetElevationForVisualization(const Eigen::Vector3d& position, double time, int max_components) const;
+
   private:
     IrregularWaveParams params_;
     std::vector<double> spectrum_;

include/hydroc/waves/regular_wave.h

@@ -43,6 +43,10 @@ class RegularWave : public WaveBase {
     Eigen::Vector3d GetVelocity(const Eigen::Vector3d& position, double time, double elevation) override;
     Eigen::Vector3d GetAcceleration(const Eigen::Vector3d& position, double time, double elevation) override;
 
+    /// Return the surface slope (∂η/∂x, ∂η/∂y) at a given position and time.
+    /// Used for computing surface normals in visualization.
+    Eigen::Vector2d GetElevationGradientXY(const Eigen::Vector3d& position, double time) const;
+
   private:
     unsigned int num_bodies_ = 0;
     const WaveMode mode_ = WaveMode::regular;

src/hydro/hydro_system.cpp

@@ -33,7 +33,6 @@
 #include <chrono/physics/ChSystemSMC.h>
 #include <chrono/physics/ChLoadHydrodynamics.h>
 #include <chrono/solver/ChIterativeSolverLS.h>
-#include <chrono/solver/ChSolverPMINRES.h>
 #include <chrono/timestepper/ChTimestepper.h>
 #include <chrono/timestepper/ChTimestepperHHT.h>
 #include <chrono/fea/ChMeshFileLoader.h>
@@ -278,11 +277,13 @@ HydroSystem::HydroSystem(std::vector<std::shared_ptr<ChBody>> user_bodies,
         force_per_body_.emplace_back(bodies_[b], this);
     }
 
-    // Handle added mass info (applied via a Chrono ChLoadHydrodynamics)
+    // Handle added mass info (applied via Chrono's ChLoadHydrodynamics).
+    // ChBodyAddedMassBlocks is a std::vector<ChBodyAddedMassBlock>; each entry
+    // pairs a body with its 6×6N row of the infinite-frequency added mass matrix.
     const auto& body_info = file_info_.GetBodyInfos();
     ChBodyAddedMassBlocks body_blocks;
-    for (size_t i = 0; i < num_bodies_; i++) {
-        body_blocks.insert(std::pair(bodies_[i], body_info[i].inf_added_mass));
+    for (int i = 0; i < num_bodies_; i++) {
+        body_blocks.push_back({bodies_[i], body_info[i].inf_added_mass});
     }
     if (num_bodies_ > 0) {
         auto hydro_load = chrono_types::make_shared<ChLoadHydrodynamics>(body_blocks);

src/hydro/runner/run_from_yaml.cpp

@@ -204,14 +204,20 @@ std::shared_ptr<chrono::ChSystem> InitializeChronoSystem(const std::string& mode
         hydroc::debug::LogDebug("Creating Chrono YAML parser");
         auto parser = chrono::parsers::ChParserMbsYAML();
 
+        // Load simulation settings (solver, integrator, visualization, etc.)
         hydroc::debug::LogDebug(std::string("Loading simulation file: ") + sim_file);
-        parser.LoadSimulationFile(sim_file);
+        auto sim_yaml = YAML::LoadFile(sim_file);
+        parser.LoadSimData(sim_yaml);
+        if (sim_yaml["solver"])
+            parser.LoadSolverData(sim_yaml);
 
         hydroc::debug::LogDebug("Creating system");
         auto system = parser.CreateSystem();
 
+        // Load MBS model (bodies, joints, etc.)
         hydroc::debug::LogDebug(std::string("Loading model file: ") + model_file);
-        parser.LoadModelFile(model_file);
+        auto model_yaml = YAML::LoadFile(model_file);
+        parser.LoadModelData(model_yaml);
 
         hydroc::debug::LogDebug("Analyzing mesh files referenced in YAML model");
         std::filesystem::path model_dir = std::filesystem::path(model_file).parent_path();