8 Commits

Author	SHA1	Message	Date
ctan	d5ad3c3aac	fix(rules): a grazed caster cell no longer shortens a line spell - SRD Aiming a Spell: a line 'starts from any corner of your square and extends to the limit of its range' (Lightning Bolt: 'The bolt begins at your fingertips'), so the caster's own squares are origin space the line starts PAST and must not consume one of the length_cells squares; line_cells took a fixed ray[1:length_cells+1] window and dropped caster cells inside it, so a 2x2 caster's line came out one square short per grazed footprint cell (the old code documented this as a simplification); the ray is now extended (reach = length_cells + 1 + len(caster_cells)) and caster cells are skipped WITHOUT spending a length slot, so a multi-cell line runs its full length starting just past the footprint; 1x1 casters are bit-identical (the only skipped cell is the origin at ray[0], already outside the counted window); the barrier/LoE stop and out-of-bounds semantics are unchanged (a straight ray never re-enters a convex map); golden untouched (no line spell in it); +3 tests (grazed-cell full-length template, 1x1 bit-identical regression, engine-level reach of a foe the short line missed)	2026-09-20 00:41:02 +02:00
ctan	b775d46850	fix(rules): document the burst center-to-center convention as a deferred SRD approximation - the SRD (aiming-a-spell.md) measures a burst from a grid INTERSECTION with the far-edge rule ('count from intersection to intersection'; a square is inside only 'if the far edge of a square is within the spell's area'), but the engine's burst origin is a CELL (target_pos, centered_on_caster, resolved target) counted center-to-center 5-10-5 in _creatures_in_range; matching RAW exactly needs an intersection coordinate added to AreaEffect/Action.target_pos/the observation area snapshot contract plus a per-caster corner choice (the far-edge boundary result depends entirely on which of the cell's four corners is the origin), so it is DEFERRED with a precise explanation in areas.py and a pointer from _creatures_in_range; no behavior change, golden untouched	2026-09-20 00:16:18 +02:00
ctan	1e2de7f89d	fix(rules): a cone/line template excludes the caster's whole footprint, not just the anchor cell (SRD aiming-a-spell.md: 'It starts from any corner of your square' - every occupied square is origin space and never inside its own area) - cone_cells/line_cells take caster_cells; combat passes caster.occupied_cells(); 1x1 casters bit-identical; documented simplification: a grazed caster cell still consumes a length slot	2026-09-19 16:34:22 +02:00
ctan	948edc1815	fix(rules): bursts cannot affect creatures in total cover from the point of origin (SRD aiming-a-spell.md: a burst "can't affect creatures with total cover from its point of origin (in other words, its effects don't extend around corners)"; Line of Effect: a burst affects only what it has LoE to from its origin) - _area_creatures skips creatures whose occupied cells have no line of effect from the burst center	2026-09-19 14:08:24 +02:00
ctan	389e160627	fix(rules): cones require line of effect from their origin (SRD aiming-a-spell.md: a cone 'affects only an area, creature, or object to which it has line of effect from its origin') - cone_cells drops geometrically-inside cells without corner-to-corner LoE from the caster square; line/cone barrier-cell semantics aligned (both templates include the barrier square the effect strikes, exclude everything behind it)	2026-09-19 14:04:34 +02:00
ctan	5250763c35	fix(rules): line spells stop at a line-of-effect barrier (SRD aiming-a-spell.md: a line 'extends to the limit of its range or until it strikes a barrier that blocks line of effect') - line_cells truncates at the first blocks_los cell, creatures behind a solid wall are never caught	2026-09-19 13:54:25 +02:00
ctan	642f449b9e	fix(rules): exclude the caster from a line spell's area ... CRB Magic - Aiming a Spell: a line 'starts from any corner of your square', so the caster's own square is outside the template (SRD Lightning Bolt: 'The bolt begins at your fingertips' - it leaves the square, it does not fill it). line_cells now drops the origin and takes the length_cells squares beyond it; a degenerate aim affects nothing. Updated the Lightning Bolt and Line Sparks tests (caster no longer caught) and the README. Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent) Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>	2026-09-13 11:30:30 +02:00
ctan	4659fae9f6	feat(rules): support cone and line spell areas ... AreaEffect gains shape: burst|cone|line (CRB Magic - Aiming a Spell). Cones (90 deg, length = radius_ft) and lines (5 ft wide, Bresenham ray) originate at the caster's cell and are aimed at the resolved target or the U7b point-cast center; bursts are unchanged. Shared per-creature save + SR application; the observation area dict already exposes the shape. Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent) Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>	2026-09-13 10:32:37 +02:00