Andrew Kesterson
d0b057f47a
A proxy is what the broad phase will index: an actor's shape, where it is, and the bounds that follow from those. It is a sixth heap layer, two per actor -- one for the actor itself and headroom for static geometry a game registers that is not tile-aligned. Solid *tiles* deliberately get none: the broad phase will read those out of the tilemap's own array, because one proxy per tile is tens of megabytes to index data that is already a grid. The pool follows the existing convention rather than improving on it. akgl_heap_next_collision_proxy finds a free slot and does not claim it; akgl_collision_proxy_initialize claims it. That is TODO.md item 8's asymmetry, and it is kept on purpose: an acquire abandoned before initialization leaks nothing, because the slot still reads as free, and a sixth pool with its own rule would be worse than one defect with five instances. Fixing item 8 means fixing all five together with every call site audited, and that is its own change. The proxy holds a *copy* of the shape rather than a pointer. An actor's own logic may rewrite its shape mid-step -- a character crouching, a projectile arming -- and a broad phase whose bounds came from a shape that has since changed is a bug that only appears when two things happen in the same frame. akgl_heap_release_actor now releases the actor's proxy. Without it the proxy holds a borrowed `owner` into a slot that has just been zeroed, so the broad phase keeps a registration whose owner reads as a free actor, and the next contact against it is a collision with nothing. Verified by removing the release and watching test_proxy_dies_with_its_actor go red. The tests pin the convention as well as the behaviour: that two acquires with no initialize between them return the same slot is asserted, not merely tolerated, so that changing the convention has to change a test that says why it exists. Co-Authored-By: Claude Code <noreply@anthropic.com> Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
29 KiB
29 KiB