Implement UIState buffer caching to eliminate per-frame malloc/free calls

src/main.cpp

@@ -45,6 +45,8 @@ void run_gui_simulation(SimulationState* sim) {
     ui_state.maneuver_list_scroll = 0;
     ui_state.selected_maneuver_index = -1;
 
+    ui_state_init_buffers(&ui_state);
+
     ui_state.maneuver_dialog.open = false;
     ui_state.maneuver_dialog.active_tab = MD_TAB_CREATE;
     ui_state.maneuver_dialog.craft_index = -1;
@@ -175,6 +177,7 @@ void run_gui_simulation(SimulationState* sim) {
     }
 
     close_renderer(&render_state);
+    ui_state_free_buffers(&ui_state);
     printf("\nSimulation ended. Final time: %.2f days\n", sim->time / 86400.0);
 }
 

src/maneuver.cpp

@@ -252,6 +252,7 @@ int add_maneuver_to_simulation(SimulationState* sim, Maneuver* maneuver) {
     sim->maneuvers[new_idx].executed = false;
     sim->maneuvers[new_idx].executed_time = 0.0;
     sim->maneuver_count++;
+    increment_sim_version(sim);
 
     return new_idx;
 }
@@ -268,6 +269,7 @@ bool remove_maneuver_by_index(SimulationState* sim, int index) {
     }
 
     sim->maneuver_count--;
+    increment_sim_version(sim);
     return true;
 }
 

src/simulation.cpp

@@ -64,6 +64,7 @@ int add_spacecraft(SimulationState* sim, Spacecraft* craft) {
     int new_idx = sim->craft_count;
     sim->spacecraft[new_idx] = *craft;
     sim->craft_count++;
+    increment_sim_version(sim);
 
     return new_idx;
 }
@@ -98,6 +99,7 @@ int add_body_to_simulation(SimulationState* sim, CelestialBody* body) {
 
     sim->bodies[new_idx].global_position = body->global_position;
     sim->bodies[new_idx].global_velocity = body->global_velocity;
+    increment_sim_version(sim);
 
     return new_idx;
 }
@@ -393,3 +395,7 @@ OrbitalAnalysis calculate_orbital_elements(CelestialBody* body, CelestialBody* p
 
     return elem;
 }
+
+void increment_sim_version(SimulationState* sim) {
+    sim->version++;
+}

src/simulation.h

@@ -46,11 +46,13 @@ struct SimulationState {
     double time;
     double dt;
     char config_name[256];
+    int version;
 };
 
 // Simulation management functions
 SimulationState* create_simulation(int max_bodies, int max_craft, int max_maneuvers, double time_step);
 void destroy_simulation(SimulationState* sim);
+void increment_sim_version(SimulationState* sim);
 
 // Dynamic body management
 int add_body_to_simulation(SimulationState* sim, CelestialBody* body);

src/ui_renderer.cpp

@@ -94,30 +94,45 @@ void render_body_list_ui(SimulationState* sim, RenderState* render_state, UIStat
     // Create list string for raygui (NULL-terminated)
     // Include both bodies and spacecraft
     int total_items = sim->body_count + sim->craft_count;
-    int buffer_size = total_items * (64 + 3 + 1) + 1; // Extra space for "🚀 " prefix
-    char* list_text = (char*)malloc(buffer_size);
-    if (!list_text) return;
 
-    list_text[0] = '\0';
+    // Check if buffer needs rebuilding
+    bool needs_rebuild = (ui_state->sim_version != sim->version) || (ui_state->body_list_buffer == NULL);
+
+    if (needs_rebuild) {
+        int buffer_size = total_items * (64 + 3 + 1) + 1;
+
+        if (ui_state->body_list_buffer == NULL || ui_state->body_list_buffer_size < buffer_size) {
+            if (ui_state->body_list_buffer != NULL) {
+                free(ui_state->body_list_buffer);
+            }
+            ui_state->body_list_buffer = (char*)malloc(buffer_size);
+            if (!ui_state->body_list_buffer) return;
+            ui_state->body_list_buffer_size = buffer_size;
+        }
+
+        ui_state->body_list_buffer[0] = '\0';
         int offset = 0;
         int item_index = 0;
 
         // Add bodies to list
         for (int i = 0; i < sim->body_count; i++) {
             if (item_index > 0) {
-            offset += snprintf(list_text + offset, buffer_size - offset, ";");
+                offset += snprintf(ui_state->body_list_buffer + offset, ui_state->body_list_buffer_size - offset, ";");
             }
-        offset += snprintf(list_text + offset, buffer_size - offset, "%s", sim->bodies[i].name);
+            offset += snprintf(ui_state->body_list_buffer + offset, ui_state->body_list_buffer_size - offset, "%s", sim->bodies[i].name);
             item_index++;
         }
 
         // Add spacecraft to list with "🚀 " prefix
         for (int i = 0; i < sim->craft_count; i++) {
-        offset += snprintf(list_text + offset, buffer_size - offset, ";");
+            offset += snprintf(ui_state->body_list_buffer + offset, ui_state->body_list_buffer_size - offset, ";");
-        offset += snprintf(list_text + offset, buffer_size - offset, "🚀 %s", sim->spacecraft[i].name);
+            offset += snprintf(ui_state->body_list_buffer + offset, ui_state->body_list_buffer_size - offset, "🚀 %s", sim->spacecraft[i].name);
             item_index++;
         }
 
+        ui_state->sim_version = sim->version;
+    }
+
     // Draw window (no close button - panels always shown)
     GuiWindowBox(panel_bounds, "Objects");
 
@@ -130,7 +145,7 @@ void render_body_list_ui(SimulationState* sim, RenderState* render_state, UIStat
     };
 
     int previous_active = ui_state->body_list_active;
-    GuiListView(list_bounds, list_text, &ui_state->body_list_scroll, &ui_state->body_list_active);
+    GuiListView(list_bounds, ui_state->body_list_buffer, &ui_state->body_list_scroll, &ui_state->body_list_active);
 
     // Check if an item was selected
     if (ui_state->body_list_active >= 0 && ui_state->body_list_active != previous_active) {
@@ -150,8 +165,6 @@ void render_body_list_ui(SimulationState* sim, RenderState* render_state, UIStat
             }
         }
     }
-
-    free(list_text);
 }
 
 // Render body information UI panel
@@ -381,27 +394,47 @@ void render_maneuver_list_ui(SimulationState* sim, RenderState* render_state, UI
         return;
     }
 
-    int buffer_size = craft_maneuver_count * (64 + 10 + 1) + 1;
-    char* maneuver_list_text = (char*)malloc(buffer_size);
-    if (!maneuver_list_text) return;
-
-    maneuver_list_text[0] = '\0';
-    int offset = 0;
     int maneuver_indices[craft_maneuver_count];
     int maneuver_index_count = 0;
 
     for (int i = 0; i < sim->maneuver_count; i++) {
         if (sim->maneuvers[i].craft_index == ui_state->selected_craft_index) {
             maneuver_indices[maneuver_index_count++] = i;
+        }
+    }
+
+    // Check if buffer needs rebuilding
+    bool needs_rebuild = (ui_state->sim_version != sim->version) || (ui_state->maneuver_list_buffer == NULL);
+
+    if (needs_rebuild) {
+        int buffer_size = craft_maneuver_count * (64 + 10 + 1) + 1;
+
+        if (ui_state->maneuver_list_buffer == NULL || ui_state->maneuver_list_buffer_size < buffer_size) {
+            if (ui_state->maneuver_list_buffer != NULL) {
+                free(ui_state->maneuver_list_buffer);
+            }
+            ui_state->maneuver_list_buffer = (char*)malloc(buffer_size);
+            if (!ui_state->maneuver_list_buffer) return;
+            ui_state->maneuver_list_buffer_size = buffer_size;
+        }
+
+        ui_state->maneuver_list_buffer[0] = '\0';
+        int offset = 0;
+
+        for (int i = 0; i < sim->maneuver_count; i++) {
+            if (sim->maneuvers[i].craft_index == ui_state->selected_craft_index) {
                 if (offset > 0) {
-                offset += snprintf(maneuver_list_text + offset, buffer_size - offset, ";");
+                    offset += snprintf(ui_state->maneuver_list_buffer + offset, ui_state->maneuver_list_buffer_size - offset, ";");
                 }
                 const char* status_char = sim->maneuvers[i].executed ? "[DONE]" : "[PENDING]";
-            offset += snprintf(maneuver_list_text + offset, buffer_size - offset, "%s %s",
+                offset += snprintf(ui_state->maneuver_list_buffer + offset, ui_state->maneuver_list_buffer_size - offset, "%s %s",
                                 status_char, sim->maneuvers[i].name);
             }
         }
 
+        ui_state->sim_version = sim->version;
+    }
+
     Rectangle list_bounds = {
         (float)panel_x + 4,
         (float)panel_y + 25,
@@ -410,7 +443,7 @@ void render_maneuver_list_ui(SimulationState* sim, RenderState* render_state, UI
     };
 
     int previous_active = ui_state->maneuver_list_active;
-    GuiListView(list_bounds, maneuver_list_text, &ui_state->maneuver_list_scroll, &ui_state->maneuver_list_active);
+    GuiListView(list_bounds, ui_state->maneuver_list_buffer, &ui_state->maneuver_list_scroll, &ui_state->maneuver_list_active);
 
     if (ui_state->maneuver_list_active >= 0 && ui_state->maneuver_list_active != previous_active) {
         if (ui_state->maneuver_list_active >= 0 && ui_state->maneuver_list_active < maneuver_index_count) {
@@ -527,8 +560,6 @@ void render_maneuver_list_ui(SimulationState* sim, RenderState* render_state, UI
             }
         }
     }
-
-    free(maneuver_list_text);
 }
 
 void render_maneuver_create_tab(SimulationState* sim, UIState* ui_state, int x, int y, int width, int height) {
@@ -713,34 +744,64 @@ void render_maneuver_hohmann_tab(SimulationState* sim, UIState* ui_state, int x,
         }
     }
 
-    GuiLabel({(float)x, (float)current_y, (float)width, 25}, "Calculate optimal Hohmann transfer between orbits");
+    if (ui_state->sim_version != sim->version) {
-    current_y += 30;
+        int craft_buffer_size = sim->craft_count * 64 + 1;
 
-    GuiLabel({(float)x, (float)current_y, 120, 25}, "Spacecraft:");
+        if (ui_state->craft_list_buffer == NULL || ui_state->craft_list_buffer_size < craft_buffer_size) {
-    current_y += 35;
+            if (ui_state->craft_list_buffer != NULL) {
+                free(ui_state->craft_list_buffer);
+            }
+            ui_state->craft_list_buffer = (char*)malloc(craft_buffer_size);
+            if (!ui_state->craft_list_buffer) return;
+            ui_state->craft_list_buffer_size = craft_buffer_size;
+        }
 
-    if (sim->craft_count > 0) {
+        ui_state->craft_list_buffer[0] = '\0';
-        static bool edit_mode_spacecraft = false;
-        int craft_buffer_size = sim->craft_count * 64 + 1;
-        char* craft_list = (char*)malloc(craft_buffer_size);
-        if (craft_list) {
-            craft_list[0] = '\0';
         int offset = 0;
         for (int i = 0; i < sim->craft_count; i++) {
             if (i > 0) {
-                    offset += snprintf(craft_list + offset, craft_buffer_size - offset, ";");
+                offset += snprintf(ui_state->craft_list_buffer + offset, ui_state->craft_list_buffer_size - offset, ";");
+            }
+            offset += snprintf(ui_state->craft_list_buffer + offset, ui_state->craft_list_buffer_size - offset, "%s", sim->spacecraft[i].name);
+        }
+
+        int body_buffer_size = sim->body_count * 64 + 1;
+
+        if (ui_state->body_dropdown_buffer == NULL || ui_state->body_dropdown_buffer_size < body_buffer_size) {
+            if (ui_state->body_dropdown_buffer != NULL) {
+                free(ui_state->body_dropdown_buffer);
+            }
+            ui_state->body_dropdown_buffer = (char*)malloc(body_buffer_size);
+            if (!ui_state->body_dropdown_buffer) return;
+            ui_state->body_dropdown_buffer_size = body_buffer_size;
+        }
+
+        ui_state->body_dropdown_buffer[0] = '\0';
+        offset = 0;
+        for (int i = 0; i < sim->body_count; i++) {
+            if (i > 0) {
+                offset += snprintf(ui_state->body_dropdown_buffer + offset, ui_state->body_dropdown_buffer_size - offset, ";");
             }
-                offset += snprintf(craft_list + offset, craft_buffer_size - offset, "%s", sim->spacecraft[i].name);
+            offset += snprintf(ui_state->body_dropdown_buffer + offset, ui_state->body_dropdown_buffer_size - offset, "%s", sim->bodies[i].name);
         }
 
+        ui_state->sim_version = sim->version;
+    }
+
+    GuiLabel({(float)x, (float)current_y, (float)width, 25}, "Calculate optimal Hohmann transfer between orbits");
+    current_y += 30;
+
+    GuiLabel({(float)x, (float)current_y, 120, 25}, "Spacecraft:");
+    current_y += 35;
+
+    if (sim->craft_count > 0) {
+        static bool edit_mode_spacecraft = false;
         if (GuiDropdownBox({(float)x + 120, (float)(current_y - 35), (float)(width - 130), 25},
-                              craft_list, &ui_state->maneuver_dialog.craft_index, edit_mode_spacecraft)) {
+                          ui_state->craft_list_buffer, &ui_state->maneuver_dialog.craft_index, edit_mode_spacecraft)) {
             edit_mode_spacecraft = !edit_mode_spacecraft;
         }
-            free(craft_list);
         if (edit_mode_spacecraft) return;
     }
-    }
     current_y += 35;
 
     GuiLabel({(float)x, (float)current_y, 120, 25}, "Transfer Parent:");
@@ -748,26 +809,12 @@ void render_maneuver_hohmann_tab(SimulationState* sim, UIState* ui_state, int x,
 
     if (sim->body_count > 0) {
         static bool edit_mode_transfer_parent = false;
-        int body_buffer_size = sim->body_count * 64 + 1;
-        char* body_list = (char*)malloc(body_buffer_size);
-        if (body_list) {
-            body_list[0] = '\0';
-            int offset = 0;
-            for (int i = 0; i < sim->body_count; i++) {
-                if (i > 0) {
-                    offset += snprintf(body_list + offset, body_buffer_size - offset, ";");
-                }
-                offset += snprintf(body_list + offset, body_buffer_size - offset, "%s", sim->bodies[i].name);
-            }
-
         if (GuiDropdownBox({(float)x + 120, (float)(current_y - 35), (float)(width - 130), 25},
-                              body_list, &ui_state->maneuver_dialog.transfer_body_index, edit_mode_transfer_parent)) {
+                          ui_state->body_dropdown_buffer, &ui_state->maneuver_dialog.transfer_body_index, edit_mode_transfer_parent)) {
             edit_mode_transfer_parent = !edit_mode_transfer_parent;
         }
-            free(body_list);
         if (edit_mode_transfer_parent) return;
     }
-    }
     current_y += 35;
 
     GuiLabel({(float)x, (float)current_y, 120, 25}, "Current Body:");
@@ -775,26 +822,12 @@ void render_maneuver_hohmann_tab(SimulationState* sim, UIState* ui_state, int x,
 
     if (sim->body_count > 0) {
         static bool edit_mode_current_body = false;
-        int body_buffer_size = sim->body_count * 64 + 1;
-        char* body_list = (char*)malloc(body_buffer_size);
-        if (body_list) {
-            body_list[0] = '\0';
-            int offset = 0;
-            for (int i = 0; i < sim->body_count; i++) {
-                if (i > 0) {
-                    offset += snprintf(body_list + offset, body_buffer_size - offset, ";");
-                }
-                offset += snprintf(body_list + offset, body_buffer_size - offset, "%s", sim->bodies[i].name);
-            }
-
         if (GuiDropdownBox({(float)x + 120, (float)(current_y - 35), (float)(width - 130), 25},
-                              body_list, &ui_state->maneuver_dialog.current_body_index, edit_mode_current_body)) {
+                          ui_state->body_dropdown_buffer, &ui_state->maneuver_dialog.current_body_index, edit_mode_current_body)) {
             edit_mode_current_body = !edit_mode_current_body;
         }
-            free(body_list);
         if (edit_mode_current_body) return;
     }
-    }
     current_y += 35;
 
     GuiLabel({(float)x, (float)current_y, 120, 25}, "Target Body:");
@@ -802,26 +835,12 @@ void render_maneuver_hohmann_tab(SimulationState* sim, UIState* ui_state, int x,
 
     if (sim->body_count > 0) {
         static bool edit_mode_target_body = false;
-        int body_buffer_size = sim->body_count * 64 + 1;
-        char* body_list = (char*)malloc(body_buffer_size);
-        if (body_list) {
-            body_list[0] = '\0';
-            int offset = 0;
-            for (int i = 0; i < sim->body_count; i++) {
-                if (i > 0) {
-                    offset += snprintf(body_list + offset, body_buffer_size - offset, ";");
-                }
-                offset += snprintf(body_list + offset, body_buffer_size - offset, "%s", sim->bodies[i].name);
-            }
-
         if (GuiDropdownBox({(float)x + 120, (float)(current_y - 35), (float)(width - 130), 25},
-                              body_list, &ui_state->maneuver_dialog.target_body_index, edit_mode_target_body)) {
+                          ui_state->body_dropdown_buffer, &ui_state->maneuver_dialog.target_body_index, edit_mode_target_body)) {
             edit_mode_target_body = !edit_mode_target_body;
         }
-            free(body_list);
         if (edit_mode_target_body) return;
     }
-    }
     current_y += 35;
 
     Rectangle calculate_btn = {(float)x, (float)current_y, (float)width, 30};
@@ -1409,3 +1428,41 @@ void delete_maneuver_from_dialog(SimulationState* sim, UIState* ui_state) {
         ui_state->maneuver_dialog.open = false;
     }
 }
+
+void ui_state_init_buffers(UIState* ui_state) {
+    ui_state->sim_version = 0;
+    ui_state->body_list_buffer_size = 0;
+    ui_state->body_list_buffer = NULL;
+    ui_state->craft_list_buffer_size = 0;
+    ui_state->craft_list_buffer = NULL;
+    ui_state->body_dropdown_buffer_size = 0;
+    ui_state->body_dropdown_buffer = NULL;
+    ui_state->maneuver_list_buffer_size = 0;
+    ui_state->maneuver_list_buffer = NULL;
+}
+
+void ui_state_free_buffers(UIState* ui_state) {
+    if (ui_state->body_list_buffer != NULL) {
+        free(ui_state->body_list_buffer);
+        ui_state->body_list_buffer = NULL;
+    }
+    ui_state->body_list_buffer_size = 0;
+
+    if (ui_state->craft_list_buffer != NULL) {
+        free(ui_state->craft_list_buffer);
+        ui_state->craft_list_buffer = NULL;
+    }
+    ui_state->craft_list_buffer_size = 0;
+
+    if (ui_state->body_dropdown_buffer != NULL) {
+        free(ui_state->body_dropdown_buffer);
+        ui_state->body_dropdown_buffer = NULL;
+    }
+    ui_state->body_dropdown_buffer_size = 0;
+
+    if (ui_state->maneuver_list_buffer != NULL) {
+        free(ui_state->maneuver_list_buffer);
+        ui_state->maneuver_list_buffer = NULL;
+    }
+    ui_state->maneuver_list_buffer_size = 0;
+}

src/ui_renderer.h

@@ -50,6 +50,16 @@ struct UIState {
     int maneuver_list_active;
     int maneuver_list_scroll;
     int selected_maneuver_index;
+
+    int sim_version;
+    int body_list_buffer_size;
+    char* body_list_buffer;
+    int craft_list_buffer_size;
+    char* craft_list_buffer;
+    int body_dropdown_buffer_size;
+    char* body_dropdown_buffer;
+    int maneuver_list_buffer_size;
+    char* maneuver_list_buffer;
 };
 
 void gui_init();
@@ -73,5 +83,7 @@ void calculate_hohmann_for_dialog(SimulationState* sim, UIState* ui_state);
 void create_hohmann_burns(SimulationState* sim, UIState* ui_state, bool create_both_burns);
 void load_maneuver_into_dialog(SimulationState* sim, UIState* ui_state, int maneuver_index);
 void delete_maneuver_from_dialog(SimulationState* sim, UIState* ui_state);
+void ui_state_init_buffers(UIState* ui_state);
+void ui_state_free_buffers(UIState* ui_state);
 
 #endif