Update load_particle.hpp

Author: TimGoTheCreator

src/io/load_particle.hpp

@@ -2,12 +2,10 @@
 // it under the terms of the GNU General Public License as published by
 // the Free Software Foundation, either version 3 of the License, or
 // (at your option) any later version.
-
 // This program is distributed in the hope that it will be useful,
 // but WITHOUT ANY WARRANTY; without even the implied warranty of
 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 // GNU General Public License for more details.
-
 // You should have received a copy of the GNU General Public License
 // along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
@@ -17,17 +15,17 @@
 #include <string>
 #include <vector>
 #include <stdexcept>
-
-// HDF5 C API
 #include <hdf5.h>
 
-// Helper: load one PartType group into particles
+/**
+ * @brief Helper: load one PartType group from HDF5 into the SoA Particle database.
+ */
 void LoadPartType(hid_t file,
                   const std::string& group,
                   int internalType,
-                  std::vector<Particle>& particles)
+                  Particle& p) // p is now the SoA container
 {
-    // Coordinates
+    // Coordinates Check
     if (H5Lexists(file, (group + "/Coordinates").c_str(), H5P_DEFAULT) <= 0)
         return;
 
@@ -36,63 +34,84 @@ void LoadPartType(hid_t file,
 
     hsize_t dims[2];
     H5Sget_simple_extent_dims(space_coords, dims, NULL);
-    size_t N = dims[0]; // number of particles
+    size_t N = dims[0]; 
 
-    std::vector<float> coords(N*3);
-    H5Dread(dset_coords, H5T_NATIVE_FLOAT, H5S_ALL, H5S_ALL, H5P_DEFAULT, coords.data());
-
-    H5Dclose(dset_coords);
-    H5Sclose(space_coords);
+    // Temporary buffers for HDF5 read
+    std::vector<float> coords(N * 3);
+    std::vector<float> vels(N * 3);
+    std::vector<float> masses(N);
 
-    // Velocities
+    // Read everything from HDF5
+    H5Dread(dset_coords, H5T_NATIVE_FLOAT, H5S_ALL, H5S_ALL, H5P_DEFAULT, coords.data());
+    
     hid_t dset_vels = H5Dopen(file, (group + "/Velocities").c_str(), H5P_DEFAULT);
-    std::vector<float> vels(N*3);
     H5Dread(dset_vels, H5T_NATIVE_FLOAT, H5S_ALL, H5S_ALL, H5P_DEFAULT, vels.data());
-    H5Dclose(dset_vels);
-
-    // Masses
+    
     hid_t dset_masses = H5Dopen(file, (group + "/Masses").c_str(), H5P_DEFAULT);
-    std::vector<float> masses(N);
     H5Dread(dset_masses, H5T_NATIVE_FLOAT, H5S_ALL, H5S_ALL, H5P_DEFAULT, masses.data());
-    H5Dclose(dset_masses);
 
-    // Convert into Particle structs
+    // --- RE-FILL SoA LANES ---
+    // We reserve space to avoid multiple reallocations
+    size_t current_size = p.x.size();
+    p.x.resize(current_size + N);
+    p.y.resize(current_size + N);
+    p.z.resize(current_size + N);
+    p.vx.resize(current_size + N);
+    p.vy.resize(current_size + N);
+    p.vz.resize(current_size + N);
+    p.m.resize(current_size + N);
+    p.type.resize(current_size + N);
+
     for (size_t i = 0; i < N; i++) {
-        Particle p;
-        p.x = coords[3*i+0];
-        p.y = coords[3*i+1];
-        p.z = coords[3*i+2];
-        p.vx = vels[3*i+0];
-        p.vy = vels[3*i+1];
-        p.vz = vels[3*i+2];
-        p.m = masses[i];
-        p.type = internalType;
-        particles.push_back(p);
+        size_t idx = current_size + i;
+        p.x[idx]  = coords[3*i+0];
+        p.y[idx]  = coords[3*i+1];
+        p.z[idx]  = coords[3*i+2];
+        p.vx[idx] = vels[3*i+0];
+        p.vy[idx] = vels[3*i+1];
+        p.vz[idx] = vels[3*i+2];
+        p.m[idx]  = masses[i];
+        p.type[idx] = internalType;
     }
+
+    // Cleanup
+    H5Dclose(dset_coords);
+    H5Dclose(dset_vels);
+    H5Dclose(dset_masses);
+    H5Sclose(space_coords);
 }
 
-std::vector<Particle> LoadParticlesFromFile(const std::string& filename)
+/**
+ * @brief Loads the Particle database from file.
+ */
+Particle LoadParticlesFromFile(const std::string& filename)
 {
-    std::vector<Particle> p;
+    Particle p; // The SoA container
 
     // --- Try HDF5 first ---
     hid_t file = H5Fopen(filename.c_str(), H5F_ACC_RDONLY, H5P_DEFAULT);
     if (file >= 0) {
-        // Load PartType1 (DM → internal type=1)
-        LoadPartType(file, "PartType1", 1, p);
-
-        // Load PartType4 (Stars → internal type=0)
-        LoadPartType(file, "PartType4", 0, p);
-
+        LoadPartType(file, "PartType1", 1, p); // DM
+        LoadPartType(file, "PartType4", 0, p); // Stars
         H5Fclose(file);
         return p;
     }
 
     // --- Fallback: plain text loader ---
     std::ifstream in(filename);
-    Particle temp;
-    while (in >> temp.x >> temp.y >> temp.z >> temp.vx >> temp.vy >> temp.vz >> temp.m >> temp.type) {
-        p.push_back(temp);
+    real tx, ty, tz, tvx, tvy, tvz, tm;
+    int tt;
+    
+    // Read column by column and push into SoA lanes
+    while (in >> tx >> ty >> tz >> tvx >> tvy >> tvz >> tm >> tt) {
+        p.x.push_back(tx);
+        p.y.push_back(ty);
+        p.z.push_back(tz);
+        p.vx.push_back(tvx);
+        p.vy.push_back(tvy);
+        p.vz.push_back(tvz);
+        p.m.push_back(tm);
+        p.type.push_back(tt);
     }
     return p;
 }