Add spacecraft rendering with maneuver visualization

- Spacecraft rendered as cyan wireframe spheres (fixed size for visibility)
- Maneuver markers as colored cubes (direction-based colors: green=prograde, red=retrograde, etc.)
- Object list now includes spacecraft with '🚀 ' prefix
- Camera follow extended to support spacecraft tracking
- Spacecraft info panel displays local coordinates and maneuver counts
- Maneuver list panel shows pending/executed status with details
- Panel renamed from 'Bodies' to 'Objects'

src/main.cpp

@@ -47,6 +47,7 @@ void run_gui_simulation(SimulationState* sim) {
 
     // Initialize UI state
     render_state.selected_body_index = root_body_index >= 0 ? root_body_index : -1;
+    render_state.selected_craft_index = -1;  // No spacecraft selected initially
     render_state.previous_selected_body = -1;  // Previous selected body index
     render_state.body_list_scroll = 0;     // Initial scroll position
     render_state.body_list_active = root_body_index >= 0 ? root_body_index : -1;  // Sync with selected body

src/renderer.cpp

@@ -46,21 +46,32 @@ void update_camera(RenderState* render_state, SimulationState* sim) {
             Vector3 body_pos = sim_to_render(body->position, render_state->distance_scale);
             render_state->camera.target = body_pos;
             render_state->camera_offset = Vector3Subtract(render_state->camera.position, body_pos);
+        } else if (render_state->selected_craft_index >= 0 && render_state->selected_craft_index < sim->craft_count) {
+            Spacecraft* craft = &sim->spacecraft[render_state->selected_craft_index];
+            Vector3 craft_pos = sim_to_render(craft->position, render_state->distance_scale);
+            render_state->camera.target = craft_pos;
+            render_state->camera_offset = Vector3Subtract(render_state->camera.position, craft_pos);
         }
     }
 
-    // Preserve distance when switching to different body
-    if (render_state->camera_follow_body && render_state->selected_body_index >= 0 &&
+    // Preserve distance when switching to different body or spacecraft
+    if (render_state->camera_follow_body) {
+        if (render_state->selected_body_index >= 0 &&
             render_state->selected_body_index != render_state->previous_selected_body &&
             render_state->selected_body_index < sim->body_count) {
             // Body selection changed - recalculate offset to maintain distance
             Vector3 body_pos = sim_to_render(sim->bodies[render_state->selected_body_index].position, render_state->distance_scale);
             render_state->camera.target = body_pos;
-        // Use current offset to maintain distance to new body
             render_state->camera.position = Vector3Add(body_pos, render_state->camera_offset);
+        } else if (render_state->selected_craft_index >= 0 && sim->craft_count > 0) {
+            // Spacecraft selected - update camera to follow it
+            Vector3 craft_pos = sim_to_render(sim->spacecraft[render_state->selected_craft_index].position, render_state->distance_scale);
+            render_state->camera.target = craft_pos;
+            render_state->camera.position = Vector3Add(craft_pos, render_state->camera_offset);
+        }
     }
 
-    // Update target position when following
+    // Update target position when following body
     if (render_state->camera_follow_body && render_state->selected_body_index >= 0 &&
         render_state->selected_body_index < sim->body_count) {
         CelestialBody* body = &sim->bodies[render_state->selected_body_index];
@@ -69,6 +80,15 @@ void update_camera(RenderState* render_state, SimulationState* sim) {
         render_state->camera.position = Vector3Add(body_pos, render_state->camera_offset);
     }
 
+    // Update target position when following spacecraft
+    if (render_state->camera_follow_body && render_state->selected_craft_index >= 0 &&
+        render_state->selected_craft_index < sim->craft_count) {
+        Spacecraft* craft = &sim->spacecraft[render_state->selected_craft_index];
+        Vector3 craft_pos = sim_to_render(craft->position, render_state->distance_scale);
+        render_state->camera.target = craft_pos;
+        render_state->camera.position = Vector3Add(craft_pos, render_state->camera_offset);
+    }
+
     // Camera rotation using camera's up vector
     Vector3 to_camera = Vector3Subtract(render_state->camera.position, render_state->camera.target);
     float camera_distance = Vector3Length(to_camera);
@@ -186,6 +206,59 @@ void render_body(CelestialBody* body, RenderState* render_state) {
     DrawSphereWires(position, radius, 16, 16, color);
 }
 
+// Render a single spacecraft as a simple geometric marker
+void render_spacecraft(Spacecraft* craft, RenderState* render_state) {
+    Vector3 position = sim_to_render(craft->position, render_state->distance_scale);
+
+    // Fixed size for visibility at solar system distances
+    float marker_radius = 5.0f;
+    Color spacecraft_color = { 0, 255, 255, 255 }; // Cyan
+
+    DrawSphereWires(position, marker_radius, 8, 8, spacecraft_color);
+}
+
+// Render a maneuver marker for a spacecraft
+void render_maneuver_marker(Spacecraft* craft, Maneuver* maneuver, RenderState* render_state) {
+    if (maneuver->executed) {
+        return; // Don't show markers for executed maneuvers
+    }
+
+    Vector3 position = sim_to_render(craft->position, render_state->distance_scale);
+
+    // Size based on delta-v magnitude
+    float marker_size = (float)(maneuver->delta_v / 100.0f); // Scale by delta-v
+    if (marker_size < 2.0f) marker_size = 2.0f;
+    if (marker_size > 10.0f) marker_size = 10.0f;
+
+    // Color based on direction
+    Color marker_color;
+    switch (maneuver->direction) {
+        case BURN_PROGRADE:
+            marker_color = (Color){ 0, 255, 0, 200 }; // Green
+            break;
+        case BURN_RETROGRADE:
+            marker_color = (Color){ 255, 0, 0, 200 }; // Red
+            break;
+        case BURN_NORMAL:
+            marker_color = (Color){ 255, 255, 0, 200 }; // Yellow
+            break;
+        case BURN_ANTINORMAL:
+            marker_color = (Color){ 255, 165, 0, 200 }; // Orange
+            break;
+        case BURN_RADIAL_IN:
+            marker_color = (Color){ 255, 0, 255, 200 }; // Magenta
+            break;
+        case BURN_RADIAL_OUT:
+            marker_color = (Color){ 0, 255, 255, 200 }; // Cyan
+            break;
+        default:
+            marker_color = (Color){ 255, 255, 255, 200 }; // White
+            break;
+    }
+
+    DrawCube(position, marker_size, marker_size, marker_size, marker_color);
+}
+
 struct OrbitalBasis {
     Vec3 periapsis_dir;
     Vec3 normal;
@@ -388,12 +461,27 @@ void render_simulation(SimulationState* sim, RenderState* render_state) {
         render_body(&sim->bodies[i], render_state);
     }
 
+    // Render all spacecraft (after bodies for visibility)
+    for (int i = 0; i < sim->craft_count; i++) {
+        render_spacecraft(&sim->spacecraft[i], render_state);
+    }
+
+    // Render maneuver markers (top layer)
+    for (int i = 0; i < sim->maneuver_count; i++) {
+        Maneuver* maneuver = &sim->maneuvers[i];
+        if (!maneuver->executed && maneuver->craft_index >= 0 && maneuver->craft_index < sim->craft_count) {
+            Spacecraft* craft = &sim->spacecraft[maneuver->craft_index];
+            render_maneuver_marker(craft, maneuver, render_state);
+        }
+    }
+
     EndMode3D();
 
     // Render UI panels (always shown)
     render_info(sim);
     render_body_list_ui(sim, render_state);
     render_body_info_ui(sim, render_state);
+    render_maneuver_list_ui(sim, render_state);
 
     EndDrawing();
 }
@@ -466,23 +554,35 @@ void render_body_list_ui(SimulationState* sim, RenderState* render_state) {
 
     Rectangle panel_bounds = { (float)panel_x, (float)panel_y, (float)panel_width, (float)panel_height };
 
-    // Create body list string for raygui (NULL-terminated)
-    int buffer_size = sim->body_count * (64 + 1) + 1;
-    char* body_list_text = (char*)malloc(buffer_size);
-    if (!body_list_text) return;
+    // 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;
 
-    body_list_text[0] = '\0';
+    list_text[0] = '\0';
     int offset = 0;
+    int item_index = 0;
 
+    // Add bodies to list
     for (int i = 0; i < sim->body_count; i++) {
-        if (i > 0) {
-            offset += snprintf(body_list_text + offset, buffer_size - offset, ";");
+        if (item_index > 0) {
+            offset += snprintf(list_text + offset, buffer_size - offset, ";");
         }
-        offset += snprintf(body_list_text + offset, buffer_size - offset, "%s", sim->bodies[i].name);
+        offset += snprintf(list_text + offset, 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(list_text + offset, buffer_size - offset, "🚀 %s", sim->spacecraft[i].name);
+        item_index++;
     }
 
     // Draw window (no close button - panels always shown)
-    GuiWindowBox(panel_bounds, "Bodies");
+    GuiWindowBox(panel_bounds, "Objects");
 
     // Draw list view (inside window, leave space for title bar)
     Rectangle list_bounds = {
@@ -493,42 +593,51 @@ void render_body_list_ui(SimulationState* sim, RenderState* render_state) {
     };
 
     int previous_active = render_state->body_list_active;
-    GuiListView(list_bounds, body_list_text, &render_state->body_list_scroll, &render_state->body_list_active);
+    GuiListView(list_bounds, list_text, &render_state->body_list_scroll, &render_state->body_list_active);
 
-    // Check if a body was selected (active changed from -1 or previous value)
-    if (render_state->body_list_active >= 0 && render_state->body_list_active < sim->body_count &&
-        render_state->body_list_active != previous_active) {
+    // Check if an item was selected
+    if (render_state->body_list_active >= 0 && render_state->body_list_active != previous_active) {
+        if (render_state->body_list_active < sim->body_count) {
+            // A body was selected
             render_state->selected_body_index = render_state->body_list_active;
-        // Enable camera follow when body is selected
+            render_state->selected_craft_index = -1;
+            render_state->camera_follow_body = true;
+            printf("Camera follow enabled for body: %s\n", sim->bodies[render_state->selected_body_index].name);
+        } else {
+            // A spacecraft was selected
+            int craft_index = render_state->body_list_active - sim->body_count;
+            if (craft_index >= 0 && craft_index < sim->craft_count) {
+                render_state->selected_body_index = -1;
+                render_state->selected_craft_index = craft_index;
                 render_state->camera_follow_body = true;
-        printf("Camera follow enabled for: %s\n", sim->bodies[render_state->selected_body_index].name);
+                printf("Camera follow enabled for spacecraft: %s\n", sim->spacecraft[craft_index].name);
+            }
+        }
     }
 
-    free(body_list_text);
+    free(list_text);
 }
 
 // Render body information UI panel
 void render_body_info_ui(SimulationState* sim, RenderState* render_state) {
-    if (render_state->selected_body_index < 0 || render_state->selected_body_index >= sim->body_count) {
-        // No body selected - render empty panel
+    // Panel dimensions
     int panel_width = 250;
     int panel_height = 300;
     int panel_x = GetScreenWidth() - panel_width - 10;
     int panel_y = 10;
 
+    if ((render_state->selected_body_index < 0 || render_state->selected_body_index >= sim->body_count) &&
+        (render_state->selected_craft_index < 0 || render_state->selected_craft_index >= sim->craft_count)) {
+        // No body or spacecraft selected - render empty panel
         Rectangle panel_bounds = { (float)panel_x, (float)panel_y, (float)panel_width, (float)panel_height };
         GuiWindowBox(panel_bounds, "Info");
         return;
     }
 
-    // Panel dimensions
-    int panel_width = 250;
-    int panel_height = 300;
-    int panel_x = GetScreenWidth() - panel_width - 10;
-    int panel_y = 10;
-
     Rectangle panel_bounds = { (float)panel_x, (float)panel_y, (float)panel_width, (float)panel_height };
 
+    // Check if a body is selected
+    if (render_state->selected_body_index >= 0 && render_state->selected_body_index < sim->body_count) {
         CelestialBody* body = &sim->bodies[render_state->selected_body_index];
 
         // Draw window (no close button - panels always shown)
@@ -607,4 +716,183 @@ void render_body_info_ui(SimulationState* sim, RenderState* render_state) {
         };
 
         GuiLabel(text_bounds, info_text);
+        return;
+    }
+
+    // Check if a spacecraft is selected
+    if (render_state->selected_craft_index >= 0 && render_state->selected_craft_index < sim->craft_count) {
+        Spacecraft* craft = &sim->spacecraft[render_state->selected_craft_index];
+
+        // Draw window (no close button - panels always shown)
+        GuiWindowBox(panel_bounds, craft->name);
+
+        // Prepare info text
+        char info_text[1024];
+        char temp_buffer[256];
+
+        snprintf(info_text, sizeof(info_text), "Name: %s", craft->name);
+
+        snprintf(temp_buffer, sizeof(temp_buffer), "Mass: %.2e kg", craft->mass);
+        strcat(info_text, "\n");
+        strcat(info_text, temp_buffer);
+
+        // Position (Local)
+        snprintf(temp_buffer, sizeof(temp_buffer), "local_position: (%.2e, %.2e, %.2e)",
+                 craft->local_position.x, craft->local_position.y, craft->local_position.z);
+        strcat(info_text, "\n");
+        strcat(info_text, temp_buffer);
+
+        // Velocity (Local)
+        double vel_mag = vec3_magnitude(craft->local_velocity);
+        snprintf(temp_buffer, sizeof(temp_buffer), "local_velocity: %.2f m/s", vel_mag);
+        strcat(info_text, "\n");
+        strcat(info_text, temp_buffer);
+
+        // Parent body
+        if (craft->parent_index >= 0 && craft->parent_index < sim->body_count) {
+            snprintf(temp_buffer, sizeof(temp_buffer), "Parent: %s", sim->bodies[craft->parent_index].name);
+        } else {
+            snprintf(temp_buffer, sizeof(temp_buffer), "Parent: None");
+        }
+        strcat(info_text, "\n");
+        strcat(info_text, temp_buffer);
+
+        // Maneuver info
+        int pending_maneuvers = 0;
+        int executed_maneuvers = 0;
+        for (int i = 0; i < sim->maneuver_count; i++) {
+            if (sim->maneuvers[i].craft_index == render_state->selected_craft_index) {
+                if (sim->maneuvers[i].executed) {
+                    executed_maneuvers++;
+                } else {
+                    pending_maneuvers++;
+                }
+            }
+        }
+
+        snprintf(temp_buffer, sizeof(temp_buffer), "Pending maneuvers: %d", pending_maneuvers);
+        strcat(info_text, "\n");
+        strcat(info_text, temp_buffer);
+
+        snprintf(temp_buffer, sizeof(temp_buffer), "Executed maneuvers: %d", executed_maneuvers);
+        strcat(info_text, "\n");
+        strcat(info_text, temp_buffer);
+
+        // Draw info text (inside window, leave space for title bar)
+        Rectangle text_bounds = {
+            (float)panel_x + 8,
+            (float)panel_y + 25,
+            (float)panel_width - 16,
+            (float)panel_height - 29
+        };
+
+        GuiLabel(text_bounds, info_text);
+        return;
+    }
+}
+
+// Render maneuver list UI panel
+void render_maneuver_list_ui(SimulationState* sim, RenderState* render_state) {
+    if (render_state->selected_craft_index < 0 || render_state->selected_craft_index >= sim->craft_count) {
+        return; // No spacecraft selected
+    }
+
+    int panel_width = 300;
+    int panel_height = 400;
+    int panel_x = GetScreenWidth() - panel_width - 10;
+    int panel_y = 320; // Below info panel
+
+    Rectangle panel_bounds = { (float)panel_x, (float)panel_y, (float)panel_width, (float)panel_height };
+
+    Spacecraft* craft = &sim->spacecraft[render_state->selected_craft_index];
+
+    // Create title with spacecraft name
+    char title[128];
+    snprintf(title, sizeof(title), "Maneuvers: %s", craft->name);
+
+    // Draw window
+    GuiWindowBox(panel_bounds, title);
+
+    // Count maneuvers for this spacecraft
+    int craft_maneuver_count = 0;
+    for (int i = 0; i < sim->maneuver_count; i++) {
+        if (sim->maneuvers[i].craft_index == render_state->selected_craft_index) {
+            craft_maneuver_count++;
+        }
+    }
+
+    if (craft_maneuver_count == 0) {
+        // No maneuvers for this spacecraft
+        Rectangle text_bounds = {
+            (float)panel_x + 8,
+            (float)panel_y + 25,
+            (float)panel_width - 16,
+            (float)panel_height - 29
+        };
+        GuiLabel(text_bounds, "No maneuvers defined");
+        return;
+    }
+
+    // Create maneuver list string for raygui
+    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;
+
+    for (int i = 0; i < sim->maneuver_count; i++) {
+        if (sim->maneuvers[i].craft_index == render_state->selected_craft_index) {
+            if (offset > 0) {
+                offset += snprintf(maneuver_list_text + offset, buffer_size - offset, ";");
+            }
+
+            const char* status_char = sim->maneuvers[i].executed ? "[DONE]" : "[PENDING]";
+            offset += snprintf(maneuver_list_text + offset, buffer_size - offset, "%s %s",
+                           status_char, sim->maneuvers[i].name);
+        }
+    }
+
+    // Draw list view (inside window, leave space for title bar)
+    Rectangle list_bounds = {
+        (float)panel_x + 4,
+        (float)panel_y + 25,
+        (float)panel_width - 8,
+        (float)panel_height - 100 // Leave space for details below
+    };
+
+    int maneuver_scroll = 0;
+    int maneuver_active = -1;
+    GuiListView(list_bounds, maneuver_list_text, &maneuver_scroll, &maneuver_active);
+
+    // Show details for first pending or last executed maneuver
+    char details_text[512];
+    details_text[0] = '\0';
+
+    for (int i = 0; i < sim->maneuver_count; i++) {
+        if (sim->maneuvers[i].craft_index == render_state->selected_craft_index) {
+            if (sim->maneuvers[i].executed) {
+                snprintf(details_text, sizeof(details_text),
+                         "Last executed:\n%s\nΔv: %.1f m/s\nTime: %.1f s",
+                         sim->maneuvers[i].name, sim->maneuvers[i].delta_v, sim->maneuvers[i].executed_time);
+            } else {
+                snprintf(details_text, sizeof(details_text),
+                         "Next pending:\n%s\nΔv: %.1f m/s",
+                         sim->maneuvers[i].name, sim->maneuvers[i].delta_v);
+                break; // Show first pending
+            }
+        }
+    }
+
+    if (details_text[0] != '\0') {
+        Rectangle details_bounds = {
+            (float)panel_x + 8,
+            (float)panel_y + (float)panel_height - 70,
+            (float)panel_width - 16,
+            65
+        };
+        GuiLabel(details_bounds, details_text);
+    }
+
+    free(maneuver_list_text);
 }

src/renderer.h

@@ -2,6 +2,8 @@
 #define RENDERER_H
 
 #include "simulation.h"
+#include "spacecraft.h"
+#include "maneuver.h"
 #include "raylib.h"
 
 // Rendering state
@@ -10,6 +12,7 @@ struct RenderState {
     double distance_scale;    // Scale factor for distances
     double size_scale;        // Scale factor for body sizes
     int selected_body_index;  // -1 = no selection
+    int selected_craft_index;  // -1 = no selection
     int previous_selected_body;  // Previous selected body index
     int body_list_scroll;     // Scroll position for body list
     int body_list_active;     // Active item index in body list
@@ -28,12 +31,15 @@ void update_camera(RenderState* render_state, SimulationState* sim);
 
 // Rendering functions
 void render_body(CelestialBody* body, RenderState* render_state);
+void render_spacecraft(Spacecraft* craft, RenderState* render_state);
+void render_maneuver_marker(Spacecraft* craft, Maneuver* maneuver, RenderState* render_state);
 void render_simulation(SimulationState* sim, RenderState* render_state);
 void render_info(SimulationState* sim);
 
 // UI rendering functions
 void render_body_list_ui(SimulationState* sim, RenderState* render_state);
 void render_body_info_ui(SimulationState* sim, RenderState* render_state);
+void render_maneuver_list_ui(SimulationState* sim, RenderState* render_state);
 
 // Scaling functions
 Vector3 scale_position(Vec3 pos, double scale);