Store and display config file name in simulation state

src/config_loader.cpp

@@ -140,6 +140,9 @@ bool load_system_config(SimulationState* sim, const char* filepath) {
 
     initialize_bodies(sim);
 
+    strncpy(sim->config_name, filepath, sizeof(sim->config_name) - 1);
+    sim->config_name[sizeof(sim->config_name) - 1] = '\0';
+
     printf("Loaded %d bodies from %s\n", body_count, filepath);
     return true;
 }

src/renderer.cpp

@@ -390,7 +390,7 @@ void render_simulation(SimulationState* sim, RenderState* render_state) {
     EndMode3D();
 
     // Render UI panels (always shown)
-    render_info(sim, "solar_system.txt");
+    render_info(sim);
     render_body_list_ui(sim, render_state);
     render_body_info_ui(sim, render_state);
 
@@ -398,10 +398,10 @@ void render_simulation(SimulationState* sim, RenderState* render_state) {
 }
 
 // Render simulation information overlay
-void render_info(SimulationState* sim, const char* config_name) {
+void render_info(SimulationState* sim) {
     // Panel dimensions
     int panel_width = 200;
-    int panel_height = 280;
+    int panel_height = 300;
     int panel_x = 10;
     int panel_y = GetScreenHeight() - panel_height - 10;
 
@@ -415,10 +415,15 @@ void render_info(SimulationState* sim, const char* config_name) {
     // Prepare info text
     char info_text[1024];
     char temp_buffer[256];
-    int offset = 0;
 
     snprintf(info_text, sizeof(info_text), "Orbital Mechanics Simulation\n\n");
 
+    // Config name
+    if (sim->config_name[0] != '\0') {
+        snprintf(temp_buffer, sizeof(temp_buffer), "Config: %s\n\n", sim->config_name);
+        strcat(info_text, temp_buffer);
+    }
+
     // Simulation time (in days)
     double days = sim->time / 86400.0;  // seconds to days
     snprintf(temp_buffer, sizeof(temp_buffer), "Time: %.2f days\n", days);

src/renderer.h

@@ -29,7 +29,7 @@ void update_camera(RenderState* render_state, SimulationState* sim);
 // Rendering functions
 void render_body(CelestialBody* body, RenderState* render_state);
 void render_simulation(SimulationState* sim, RenderState* render_state);
-void render_info(SimulationState* sim, const char* config_name);
+void render_info(SimulationState* sim);
 
 // UI rendering functions
 void render_body_list_ui(SimulationState* sim, RenderState* render_state);

src/simulation.cpp

@@ -13,6 +13,7 @@ SimulationState* create_simulation(int max_bodies, double time_step) {
     sim->max_bodies = max_bodies;
     sim->time = 0.0;
     sim->dt = time_step;
+    sim->config_name[0] = '\0';
     return sim;
 }
 

src/simulation.h

@@ -26,6 +26,7 @@ struct SimulationState {
     int max_bodies;
     double time;              // simulation time (seconds)
     double dt;                // time step (seconds)
+    char config_name[256];    // name of the config file loaded
 };
 
 // Simulation management functions