add session summary

docs/session_summaries/2025-02-06-ui-buffer-caching-optimization.md

@@ -0,0 +1,65 @@
+# 2025-02-06-ui-buffer-caching-optimization
+
+## Changes Made
+
+### Commit 1: 79a972a - Fix GuiDropdownBox behavior with static edit mode variables
+- Fixed 7 dropdown controls that were incorrectly sharing edit mode variables
+- Each dropdown now has its own static `editMode` variable
+- Affected controls: orbit type, body/craft selection, burn direction, trigger type
+- Updated maneuver dialog progress documentation
+
+### Commit 2: b37497a - Implement UIState buffer caching to eliminate per-frame malloc/free calls
+- Implemented comprehensive buffer caching system in UIState
+- Cached 4 buffer types:
+  - Body names list (for object selection dropdown)
+  - Spacecraft names list (for object selection dropdown)
+  - Maneuver names list (for maneuver info display)
+  - Maneuver status strings list
+- Added `needs_update` flags for each cached buffer
+- Added `last_counts` to track when buffers need invalidation
+- Eliminated all per-frame malloc/free calls in ui_render_info_panel_objects()
+- Eliminated all per-frame malloc/free calls in ui_render_info_panel_selected()
+- Integrated cache invalidation into main loop and maneuver execution
+
+### Commit 3: 028b8a8 - Fix UI buffer caching: remove dead code, use count-based invalidation, fix update bug
+- Removed dead code from simulation.cpp/h (52 lines removed, 16 lines from header)
+- Simplified invalidation logic: removed `buffer_valid` flag in favor of count-based checks
+- Fixed bug where maneuver status cache was not being updated after maneuver execution
+- Separated concerns: ui_renderer handles UI cache, simulation module no longer has UI code
+
+### Commit 4: c76380f - Fix UI: maneuver status updates, ZII initialization, helper functions for cache checks
+- Fixed maneuver status update bug: status strings now properly update after execution
+- Fixed ZII initialization in ui_render_info_panel_selected: all state variables now use `= {0}`
+- Added helper functions:
+  - `check_needs_update_simcount()` - checks if cache needs update based on body count
+  - `check_needs_update_craftcount()` - checks if cache needs update based on craft count
+  - `check_needs_update_maneuvercount()` - checks if cache needs update based on maneuver count
+- Refactored buffer update logic to use helper functions for clarity
+- Updated AGENTS.md with command reference for testing
+
+## Results
+
+**Net line count changes:**
+- Insertions: 322
+- Deletions: 179
+- **Net: +143 lines**
+
+## Functionality Implemented
+
+### Buffer Caching System
+- Dynamic array allocation only when counts change
+- Automatic cache invalidation based on body/craft/maneuver counts
+- Helper functions for count-based cache invalidation checks
+- Integration points:
+  - `main_loop()` - invalidates caches before rendering
+  - `execute_maneuver()` - invalidates maneuver cache after execution
+
+### UI Improvements
+- Fixed all dropdown controls with static edit mode variables
+- Proper separation of concerns between UI and simulation modules
+- Cleaner, more maintainable cache update logic
+
+### Code Quality
+- ZII (Zero Is Initialization) pattern applied to UIState
+- Removed 52 lines of dead code from simulation module
+- Better code organization with helper functions