Debug Tips

1) Start with the smallest failing scope

When something breaks, isolate first:

• parser issue: run with invalid or edge-case .cub files only
• movement issue: test on a tiny closed map
• render issue: test with one texture family
• bonus issue: run ./cub3D_bonus on a minimal bonus map

Do not debug multiple subsystems at once.

2) Use staged validation commands

Run this sequence after each fix:

make
make bonus
norminette include srcs srcs_bonus
make test
make test_bonus

Then run Valgrind only on the scenario that still fails.

3) Parser and validation debugging

If startup fails before the window opens:

• print which parser step fails (headers, map_start, validate_map)
• test with a known-good map first, then mutate one field at a time
• compare the failure against the expected rejection category

Typical categories:

• missing or duplicate header
• bad texture path
• bad RGB
• invalid map symbol
• enclosure leak

This avoids chasing the wrong assumption.

4) Render debugging

For wall deformation or wrong texture orientation:

• verify perp_dist, draw_start, and draw_end
• inspect wall_x, tex_x, and tex_y
• verify face-flip conditions for tex_x
• temporarily force one wall texture to isolate selection vs mapping bugs

If visuals look sheared, suspect tex_y stepping or initial texture offset first.

5) Collision and door debugging

If the player clips through geometry or gets blocked unexpectedly:

• log attempted (dx, dy) and final applied position
• test axis-by-axis movement near corners
• print door tile, state, and progress during interaction
• compare collision queries against raycast visibility for the same tile

Movement and rendering must agree on door passability.

6) Sprite debugging

If sprites render in the wrong order or through walls:

• confirm zbuf[x] is written during raycast
• verify sprite sort uses descending distance
• inspect projection depth and screen bounds (x0, x1, y0, y1)
• check opaque filtering in the texel draw path

7) HUD and minimap layout debugging

If UI elements overlap or drift:

• log panel anchors and computed widths
• verify the resolution-change path recomputes placements
• test at F1, F2, and F3 presets
• keep HUD drawing at the end of the pipeline

8) Memory and shutdown debugging

For leaks or double-free suspects:

valgrind --leak-check=full --track-fds=yes ./cub3D <map.cub>

Verify cleanup order:

• images
• window
• display
• pointers and maps

On transfer or reload paths, ensure moved ownership is nulled before freeing temporary contexts.

9) Fast regression prevention

After each meaningful fix:

• reproduce the bug on a minimal map
• apply a focused patch
• rerun the same scenario
• run the full smoke sequence (make test, make test_bonus)
• commit only when the fix is both effective and non-regressive

10) Defense-oriented debugging habit

Keep a short log of known and fixed issues:

• symptom
• root cause
• file or function changed
• how the fix was verified

This improves both technical quality and defense clarity.