From 524db0cf19648e3c7c78d3e73103b7a0bdcd6bfc Mon Sep 17 00:00:00 2001 From: Vito Caputo Date: Wed, 18 Jan 2017 17:14:52 -0800 Subject: *: move source into src/ subdir Restoring some organizational sanity since adopting autotools. --- src/modules/sparkler/particles.c | 342 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 342 insertions(+) create mode 100644 src/modules/sparkler/particles.c (limited to 'src/modules/sparkler/particles.c') diff --git a/src/modules/sparkler/particles.c b/src/modules/sparkler/particles.c new file mode 100644 index 0000000..0eb260e --- /dev/null +++ b/src/modules/sparkler/particles.c @@ -0,0 +1,342 @@ +#include +#include +#include +#include +#include +#include +#include +#include + +#include "fb.h" + +#include "chunker.h" +#include "container.h" +#include "bsp.h" +#include "list.h" +#include "particle.h" +#include "particles.h" +#include "v3f.h" + +#define ZCONST 0.4f + +/* private particle with all the particles bookkeeping... */ +typedef struct _particle_t { + list_head_t siblings; /* sibling particles */ + list_head_t children; /* children particles */ + + particle_props_t props; /* we reference this in the public particle, I might change + * the way props are allocated so coding everything to use a + * reference for now. It may make sense to have props allocated + * separately via their own chunker, and perform some mass operations + * against the list of chunks rather than chasing the pointers of + * the particle heirarchy. TODO + */ + particle_t public; /* the public particle_t is embedded */ + + uint8_t context[]; /* particle type-specific context [public.ops.context_size] */ +} _particle_t; + +struct particles_t { + chunker_t *chunker; /* chunker for variably-sized particle allocation (includes context) */ + list_head_t active; /* top-level active list of particles heirarchy */ + bsp_t *bsp; /* bsp spatial index of the particles */ +}; + + +/* create a new particle system */ +particles_t * particles_new(void) +{ + particles_t *particles; + + particles = calloc(1, sizeof(particles_t)); + if (!particles) { + return NULL; + } + + particles->chunker = chunker_new(sizeof(_particle_t) * 128); + if (!particles->chunker) { + return NULL; + } + + particles->bsp = bsp_new(); + if (!particles->bsp) { + return NULL; + } + + INIT_LIST_HEAD(&particles->active); + + return particles; +} + + +/* TODO: add a public interface for destroying particles? for now we just return PARTICLE_DEAD in the sim */ +static inline void _particles_free_particle(particles_t *particles, _particle_t *p) +{ + assert(p); + + particle_cleanup(particles, &p->public); + chunker_free(p); +} + + +static inline void _particles_free(particles_t *particles, list_head_t *list) +{ + _particle_t *p, *_p; + + assert(particles); + assert(list); + + list_for_each_entry_safe(p, _p, list, siblings) { + _particles_free(particles, &p->children); + _particles_free_particle(particles, p); + } +} + + +/* free up all the particles */ +void particles_free(particles_t *particles) +{ + assert(particles); + + _particles_free(particles, &particles->active); +} + + +/* reclaim a dead particle, moving it to the free list */ +static void particles_reap_particle(particles_t *particles, _particle_t *particle) +{ + assert(particles); + assert(particle); + + if (!list_empty(&particle->children)) { + /* adopt any orphaned children using the global parts list */ + list_splice(&particle->children, &particles->active); + } + + list_del(&particle->siblings); + bsp_delete_occupant(particles->bsp, &particle->public.occupant); + _particles_free_particle(particles, particle); +} + + +/* add a particle to the specified list */ +static inline int _particles_add_particle(particles_t *particles, list_head_t *list, particle_props_t *props, particle_ops_t *ops) +{ + _particle_t *p; + + assert(particles); + assert(ops); + assert(list); + + p = chunker_alloc(particles->chunker, sizeof(_particle_t) + ops->context_size); + if (!p) { + return 0; + } + + INIT_LIST_HEAD(&p->children); + INIT_LIST_HEAD(&p->siblings); + + /* inherit the parent's properties and ops if they're not explicitly provided */ + if (props) { + p->props = *props; + } else { + p->props.of_use = 0; + } + + p->public.props = &p->props; + p->public.ops = ops; + + if (ops->context_size) { + p->public.ctxt = p->context; + } + + if (!particle_init(particles, &p->public)) { + /* XXX FIXME this shouldn't be normal, we don't want to allocate + * particles that cannot be initialized. the rockets today set a cap + * by failing initialization, that's silly. */ + chunker_free(p); + return 0; + } + + p->public.props->of_use = 1; + list_add(&p->siblings, list); + bsp_add_occupant(particles->bsp, &p->public.occupant, &p->props.position); + + return 1; +} + + +/* add a new "top-level" particle of the specified props and ops taking from the provided parts list */ +int particles_add_particle(particles_t *particles, particle_props_t *props, particle_ops_t *ops) +{ + assert(particles); + + return _particles_add_particle(particles, &particles->active, props, ops); +} + + +/* spawn a new child particle from a parent, initializing it via inheritance if desired */ +void particles_spawn_particle(particles_t *particles, particle_t *parent, particle_props_t *props, particle_ops_t *ops) +{ + _particle_t *p = container_of(parent, _particle_t, public); + + assert(particles); + assert(parent); + + _particles_add_particle(particles, &p->children, props ? props : parent->props, ops ? ops : parent->ops); +} + + +/* plural version of particle_add(); adds multiple "top-level" particles of uniform props and ops */ +void particles_add_particles(particles_t *particles, particle_props_t *props, particle_ops_t *ops, int num) +{ + int i; + + assert(particles); + + for (i = 0; i < num; i++) { + _particles_add_particle(particles, &particles->active, props, ops); + } +} + + +/* Simple accessor to get the bsp pointer, the bsp is special because we don't want to do + * callbacks per-occupant, so the bsp_occupant_t and search functions are used directly by + * the per-particle code needing nearest-neighbor search. that requires an accessor since + * particles_t is opaque. This seemed less shitty than opening up particles_t. + */ +bsp_t * particles_bsp(particles_t *particles) +{ + assert(particles); + assert(particles->bsp); + + return particles->bsp; +} + + +static inline void _particles_draw(particles_t *particles, list_head_t *list, fb_fragment_t *fragment) +{ + float w2 = fragment->width * .5f, h2 = fragment->height * .5f; + _particle_t *p; + + assert(particles); + assert(list); + assert(fragment); + + list_for_each_entry(p, list, siblings) { + int x, y; + + /* project the 3d coordinates onto the 2d plane */ + x = (p->props.position.x / (p->props.position.z - ZCONST) * w2) + w2; + y = (p->props.position.y / (p->props.position.z - ZCONST) * h2) + h2; + + particle_draw(particles, &p->public, x, y, fragment); + + if (!list_empty(&p->children)) { + _particles_draw(particles, &p->children, fragment); + } + } +} + + +/* draw all of the particles, currently called in heirarchical order */ +void particles_draw(particles_t *particles, fb_fragment_t *fragment) +{ + assert(particles); + + _particles_draw(particles, &particles->active, fragment); +} + + +static inline particle_status_t _particles_sim(particles_t *particles, list_head_t *list) +{ + particle_status_t ret = PARTICLE_DEAD, s; + _particle_t *p, *_p; + + assert(particles); + assert(list); + + list_for_each_entry_safe(p, _p, list, siblings) { + if ((s = particle_sim(particles, &p->public)) == PARTICLE_ALIVE) { + ret = PARTICLE_ALIVE; + + if (!list_empty(&p->children) && + _particles_sim(particles, &p->children) == PARTICLE_ALIVE) { + ret = PARTICLE_ALIVE; + } + } else { + particles_reap_particle(particles, p); + } + } + + return ret; +} + + +/* simulate the particles, call the sim method of every particle in the heirarchy, this is what makes the particles dynamic */ +/* if any paticle is still living, we return PARTICLE_ALIVE, to inform the caller when everything's dead */ +particle_status_t particles_sim(particles_t *particles) +{ + assert(particles); + + return _particles_sim(particles, &particles->active); +} + + +static inline void _particles_age(particles_t *particles, list_head_t *list) +{ + _particle_t *p; + + assert(particles); + assert(list); + + /* TODO: since this *only* involves the properties struct, if they were + * allocated from a separate slab containing only properties, it'd be + * more efficient to iterate across property arrays and skip inactive + * entries. This heirarchical pointer-chasing recursion isn't + * particularly good for cache utilization. + */ + list_for_each_entry(p, list, siblings) { +#if 1 + if (p->props.mass > 0.0f) { + /* gravity, TODO: mass isn't applied. */ + static v3f_t gravity = v3f_init(0.0f, -0.05f, 0.0f); + + p->props.direction = v3f_add(&p->props.direction, &gravity); + p->props.direction = v3f_normalize(&p->props.direction); + } +#endif + +#if 1 + /* some drag/resistance proportional to velocity TODO: integrate mass */ + if (p->props.velocity > 0.0f) { + p->props.velocity -= ((p->props.velocity * p->props.velocity * p->props.drag)); + if (p->props.velocity < 0.0f) { + p->props.velocity = 0; + } + } +#endif + + /* regular movement */ + if (p->props.velocity > 0.0f) { + v3f_t movement = v3f_mult_scalar(&p->props.direction, p->props.velocity); + + p->props.position = v3f_add(&p->props.position, &movement); + bsp_move_occupant(particles->bsp, &p->public.occupant, &p->props.position); + } + + if (!list_empty(&p->children)) { + _particles_age(particles, &p->children); + } + } +} + + +/* advance time for all the particles (move them), this doesn't currently invoke any part-specific helpers, it's just applying + * physics-type stuff, moving particles according to their velocities, directions, mass, drag, gravity etc... */ +void particles_age(particles_t *particles) +{ + assert(particles); + + _particles_age(particles, &particles->active); +} -- cgit v1.2.1