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#include <stdarg.h>
#include <stdlib.h>
#include "til_fb.h"
#include "helpers.h"
#include "particle.h"
#include "particles.h"
#include "xplode.h"
/* a "xplode" particle type, emitted by rockets in large numbers at the end of their duration */
extern particle_ops_t spark_ops;
particle_ops_t xplode_ops;
typedef struct _xplode_ctxt_t {
#define PARAMS_DECLARE_STRUCT
#include "xplode_params.def"
int remaining;
} xplode_ctxt_t;
static int xplode_init(particles_t *particles, const particles_conf_t *conf, particle_t *p, unsigned n_params, va_list params)
{
xplode_ctxt_t *ctxt = p->ctxt;
#define PARAMS_ASSIGN_DEFAULTS
#include "xplode_params.def"
for (; n_params; n_params--) {
switch (va_arg(params, xplode_param_t)) {
#define PARAMS_IMPLEMENT_SWITCH
#include "xplode_params.def"
default:
return 0;
}
}
ctxt->remaining = ctxt->duration;
p->props->drag = 10.5;
p->props->mass = 0.3;
p->props->virtual = 0;
return 1;
}
static particle_status_t xplode_sim(particles_t *particles, const particles_conf_t *conf, particle_t *p, til_fb_fragment_t *f)
{
xplode_ctxt_t *ctxt = p->ctxt;
if (!ctxt->remaining || (ctxt->remaining -= ctxt->decay_rate) <= 0) {
ctxt->remaining = 0;
return PARTICLE_DEAD;
}
/* litter some small sparks behind the explosion particle */
if (!(ctxt->duration % 30)) {
particle_props_t props = *p->props;
props.velocity = (float)rand_within_range(conf->seedp, 10, 50) * .0001;
particles_spawn_particle(particles, p, &props, &xplode_ops, 1, XPLODE_PARAM_COLOR_UINT, ctxt->color);
}
return PARTICLE_ALIVE;
}
static void xplode_draw(particles_t *particles, const particles_conf_t *conf, particle_t *p, int x, int y, til_fb_fragment_t *f)
{
xplode_ctxt_t *ctxt = p->ctxt;
uint32_t color;
if (!should_draw_expire_if_oob(particles, p, x, y, f, &ctxt->remaining))
return;
if (ctxt->remaining == ctxt->duration) {
/* always start with a white flash */
color = makergb(0xff, 0xff, 0xa0, 1.0);
} else {
color = makergb((ctxt->color & 0xff0000) >> 16, (ctxt->color & 0xff00) >> 8, ctxt->color & 0xff, ((float)ctxt->remaining / ctxt->duration));
}
til_fb_fragment_put_pixel_unchecked(f, 0, x, y, color);
}
particle_ops_t xplode_ops = {
.context_size = sizeof(xplode_ctxt_t),
.sim = xplode_sim,
.init = xplode_init,
.draw = xplode_draw,
.cleanup = NULL,
};
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