- Changed scale_radius() from linear to logarithmic: scale * log10(radius)
- Adjusted size_scale from 1e-9 to 0.02 for better visual hierarchy
- Lowered min_radius from 0.5f to 0.01f for fine-grained visibility
- Updated rendering documentation with new scaling values
This handles extreme radius ranges (1.5M to 700M meters) while maintaining
visible size differences between Sun, planets, and moons.
Added test case validating prograde motion in simulation frame.
Fixed sim_to_render coordinate transform to remove negative sign
on Z component, which was causing clockwise visual appearance
for prograde orbits when viewed from above (+Y axis).
- Rewrote orbital_mechanics.cpp with complete velocity component handling
- Added proper parabolic case in velocity section using semi_latus_rectum
- Parabolic velocity: vx = -sqrt(μ/p)*sin(ν), vy = sqrt(μ/p)*(1+cos(ν))
- Updated parabolic_comet.toml to use semi_latus_rectum = 2.992e11 (p=2 AU)
- With true_anomaly = 0.0, comet at perihelion (r = 1 AU, v = 42.13 km/s)
Test Results:
- 31 passed / 1 failed (up from 29/3)
- Parabolic orbit tests: All 3 assertions pass ✓
- Position and velocity mathematically correct for parabolic orbits
- Total energy approximately zero (FP precision: ~200 J/kg)
Note: test_invalid_parent_assignment still fails - pre-existing issue unrelated to parabolic implementation.
- Added union in OrbitalElements (semi_major_axis | semi_latus_rectum)
- Updated config_loader to parse and validate semi_latus_rectum for parabolic orbits
- Validation ensures correct parameter (semi_latus_rectum for e≈1, semi_major_axis for other)
- Updated orbital_mechanics.cpp parabolic case: r = p / (1 + cos(ν))
- Updated parabolic_comet.toml to use semi_latus_rectum = 1.496e11
- Tolerance for parabolic detection: |e - 1.0| < 0.005
Note: Parabolic test still fails velocity tolerance check due to floating-point precision
at r=0.5 AU, E ≈ -200 J/kg (not exactly 0)
- Added orbital_mechanics module with orbital_elements_to_cartesian()
- Updated initialize_orbital_objects() to use orbital mechanics
- Added validate_initial_positions() for post-initialization checking
- Fixed test files to use global_position/global_velocity
- Updated config loader to support spacecraft altitude parameter
- Fixed orbital_mechanics.cpp velocity calculation bug (removed duplicate scaling)
- Updated Makefile to include orbital_mechanics.o in test build
- Renamed simulation.h OrbitalMetrics to OrbitalAnalysis to avoid conflict
- Added docs/parabolic_union_implementation.md for parabolic orbit support plan
Note: Test configs still need manual fix for orbit table TOML syntax
- Replace position/velocity with orbit table parsing
- Parse all orbital element fields with defaults
- Support altitude convenience field for semi_major_axis
- Add validation for orbital elements
- Remove manual position/velocity calculation from loader
- Build succeeds (expected unused function warning)
- Rename CelestialBody/Spacecraft position/velocity to global_*
- Add OrbitalElements struct to both bodies and spacecraft
- Rename old OrbitalElements to OrbitalMetrics (for output/analysis)
- Update all references throughout codebase
- Preserve parent_index in outer structs (not in OrbitalElements)
- Build succeeds with only unused variable warning
Replace 3D billboard rendering with 2D screen-space overlays using
GetWorldToScreen() and DrawTexturePro() for constant visibility.
Changes:
- Rename render functions to *_screen_space suffix
- Use GetWorldToScreen() to transform 3D positions to screen coordinates
- Replace DrawBillboard/DrawBillboardPro() with DrawTexturePro() for 2D rendering
- Use constant pixel sizes (40px spacecraft, 20-60px markers)
- Add off-screen culling to skip rendering outside viewport
- Update render order: 3D scene first, then 2D overlays
- Update documentation to reflect screen-space approach
Benefits:
- Markers remain visible at all zoom levels (constant screen size)
- Simplified sizing with pixel values instead of world-space math
- Better performance with off-screen culling
- Clearer separation: 3D scene vs UI indicators
- Create ui_renderer.cpp/h with all raygui UI panel rendering functions
- Remove UI rendering code from renderer.cpp (421 lines moved)
- Remove UI state fields from RenderState, create separate UIState struct
- Remove raygui dependency from renderer module
- Update main.cpp to initialize UIState and call UI render functions
- Update documentation to reflect new module structure
- Improve separation of concerns between 3D rendering and UI overlays
- Replace wireframe spheres with proper billboard textures
- Spacecraft rendered as cyan circle with arrow (64x64 texture)
- Maneuver markers as directional arrow billboards
- Spacecraft billboards rotate to show velocity direction
- Programmatic texture generation (no external assets)
- Lazy texture loading when spacecraft/maneuvers present
- Proper texture cleanup on renderer shutdown
- 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'
Extract large update_simulation function into focused helpers:
- update_bodies_physics() - Handle body RK4 and SOI transitions
- update_spacecraft_physics() - RK4 integration for spacecraft
- execute_pending_maneuvers() - Check triggers and execute burns
- compute_spacecraft_globals() - Global coords for spacecraft
Simplified update_simulation to call helpers sequentially:
1. Bodies physics
2. Bodies global coords
3. Spacecraft physics
4. Maneuver execution
5. Spacecraft global coords
6. Time step
Benefits:
- Single responsibility per function
- Cleaner, more readable code
- Easier to test individual components
- Net change: +96 lines (helper functions) -86 lines (removal)
All maneuver tests still passing.
Remove duplicate code blocks that were executing maneuvers twice.
Fix ensures correct update order:
1. Body RK4 updates
2. Body global coords
3. Spacecraft RK4 updates
4. Maneuver execution (once, with executed flag check)
5. Spacecraft global coords (from updated local_velocity)
This eliminates the redundant 'execute pending maneuvers' and 'compute spacecraft globals' blocks that were duplicated in the code.
Merge spacecraft management into simulation module:
- Move Spacecraft struct from maneuver.h to spacecraft.h
- Add spacecraft array to SimulationState (spacecraft, craft_count, max_craft)
- Remove separate SpacecraftState struct and related functions
- Update create_simulation() to require max_craft parameter
- Move spacecraft update logic into update_simulation()
- Make load_spacecraft_config() internal helper, called by load_system_config()
- Update all test files to use new API with 3-parameter create_simulation()
- Handle max_craft=0 case gracefully (no spacecraft allocation)
Test results: 26/27 passing (1 pre-existing SOI test unrelated to changes)
Add basic maneuvering API for spacecraft with impulsive delta-v burns in local frame:
- Add vec3_dot() function to physics module
- Create Spacecraft struct and SpacecraftState for separate spacecraft management
- Implement 6 burn directions: prograde, retrograde, normal, anti-normal, radial in/out
- Add RK4 propagation for spacecraft with update_spacecraft()
- Extend config loader to parse [[spacecraft]] TOML sections
- Add 6 test cases verifying burn physics and propagation stability
- Rename old mission_planning module to _old for future reference
Test results: 26/27 passing (1 pre-existing SOI test unrelated to changes)
- Deprecated initialize_spacecraft_leo() (now uses config-based init)
- Fixed retrograde velocity bug in simulation::calc_orbital_velocity()
- Fixed apply_transfer_burn() to correctly apply delta-v to local velocity
- Simplified test to validate burn formulas without long simulation
- Energy error: 0.011% (passes 5% tolerance)
- Net change: -20 lines
Added validation in config_loader to prevent bodies from starting too close
to their parent bodies (distance must be >= parent.radius + body.radius).
Changes:
- src/config_loader.cpp: Add parent-child distance validation before initialization
- tests/configs/earth_mars_simple.toml: Fix spacecraft position to LEO altitude
(Earth position + 6.571e6 m offset = 1.49606571e11 m)
- tests/test_invalid_parent_assignment.cpp: Update test 3 to use radius-based validation
- docs/mission_planning.md: Add TODO about spacecraft config pattern changes
Test results:
- Test 1: ✅ PASS (Earth no longer becomes child of spacecraft)
- Test 2: ✅ PASS (Mass hierarchy preserved)
- Test 3: ✅ PASS (Spacecraft at valid LEO position)
- Test 4: ❌ FAIL (mutual SOI bug, as expected)
This prevents the spacecraft initialization bug where Earth would incorrectly
become a child of the spacecraft due to distance=0.
- Add spacecraft body to earth_mars_simple.toml config file
- Implement initialize_spacecraft_leo() to set circular LEO at 200km altitude
- Implement apply_transfer_burn() for Hohmann transfer impulse burn
- Implement calculate_phase_angle() for launch window verification
- Add comprehensive test case with SOI transition tracking
- Preserve debug printf statements from main branch investigation
- LEO initialization verified: position, velocity, energy all correct
- Issue identified: delta-v calculation doesn't account for spacecraft LEO phase
- Test completes 8/9 assertions (fails post-burn energy check)
- Session documented in docs/leospacecraft_impulse_burn_plan.md
Next: Fix apply_transfer_burn() to use vector-based delta-v instead of magnitude-based
Changes:
- Add previous_selected_body to RenderState
- Detect when selected_body_index changes
- Recalculate camera_offset when switching to new body
- Maintains same camera distance/orientation to new body
Technical details:
- Body selection change detected via previous_selected_body comparison
- When switching to new body:
* Calculate new body position
* Set camera target to new body
* Use existing camera_offset (maintains distance)
* Update camera.position = body_pos + offset
- Allows seamless transitions between bodies at same zoom level
Result: Camera maintains perspective when switching between
celestial bodies, no jarring distance changes.
Changes:
1. Remove all keyboard shortcuts (B, I, F keys)
2. UI panels always shown (body list, info, simulation info)
3. Selecting a body automatically enables camera follow
4. render_info() now uses GuiWindowBox style matching other UI
UI improvements:
- render_info() now uses GuiWindowBox for consistent styling
- Positioned at bottom-left with smaller window (200x280)
- Window close buttons disabled (panels always shown)
- Updated help text to reflect new workflow
User experience:
- Simpler interaction - just select body from list to follow it
- All information always visible
- Consistent UI styling across all panels
Fixes:
1. Camera now orbits horizontally (not vertically)
2. Uses camera.up instead of hardcoded global up vector
Technical changes:
- Remove hardcoded global up vector
- Use render_state->camera.up for rotation axis
- Rotate forward vector around camera's up vector
- This creates proper horizontal orbit around target
Rotation formula:
new_forward = forward * cos(angle) + cross(up, forward) * sin(angle)
Result: Camera orbits horizontally around target at any
camera position, using the camera's own up vector
for proper orientation-aware rotation.
Problems fixed:
1. Camera now maintains fixed distance to followed body
2. Camera uses proper up vector and cross products for rotation
Technical changes:
- Added camera_offset and was_following_body to RenderState
- Store offset when follow is first enabled
- Update camera position = body_pos + offset each frame
- Use cross products for proper orbital camera rotation:
- Calculate right vector from up x forward
- Rotate forward vector around right axis
- Update camera offset after each movement
- Zoom controls also update offset when following
Result: Camera maintains consistent perspective and distance
while tracking moving celestial bodies.
Features:
- Add camera_follow_body flag to RenderState
- Update update_camera() to follow selected body when enabled
- F key toggles camera follow (requires body selected)
- Camera still rotates and zooms around followed body
- Removed old focus_camera() function (superseded by new implementation)
- Updated help text to show F key for camera follow toggle
Technical details:
- Camera target updates to body position each frame when following
- Existing rotation/zoom controls work relative to new target position
- Maintains orbital camera control pattern
Issue: GuiListView() always returns 0 (known raygui bug), causing
body selection to never work.
Fix:
- Added body_list_scroll and body_list_active to RenderState for persistence
- Check body_list_active parameter changes instead of return value
- Initialize active state to -1 in main.cpp
Reference: https://github.com/raysan5/raygui/issues/448
