void update(Particles *uemitter, Particle* part, int partNumber)
{
Particles uemit = *uemitter;
Uint32 timeElapsed;
Uint32 curr = getMilliCount();
timeElapsed = curr - uemit.m_lastRender;
//printf("get -elapsed %d emitter last render %d\n", timeElapsed, emitter->m_lastRender);
uemit.particles[partNumber].m_age += timeElapsed;
if (!isAlive(&(uemit.particles[partNumber])))
{
printf("Dead\n");
//printf( "age %u timedie %u\n", part->m_age, part->m_timeDie);
// smoke eventually dies
/*if (r01() > emitter.m_dieRate)
{
part->m_canRegen = FALSE;
}
if (!part->m_canRegen)
{
return;
}*/
// regenerate
uemit.particles[partNumber].m_age = 1;
startRand(&uemit, &(uemit.particles[partNumber]), partNumber);
*uemitter = uemit;
return;
}
// At start the particle fades in and expands rapidly (like in real life)
double fadeIn = uemit.particles[partNumber].m_timeDie * 0.01;
double startScale;
double maxStartScale = 0.4;
if (uemit.particles[partNumber].m_age < fadeIn)
{
uemit.particles[partNumber].m_alpha = ((uemit.particles[partNumber].m_age / fadeIn));
//printf("fade calc = %f \n", (part->m_age/fadeIn)*10 );
startScale = uemit.particles[partNumber].m_alpha * maxStartScale;
// y increases quicker because particle is expanding quicker
uemit.particles[partNumber].m_y += uemit.particles[partNumber].m_yVector * timeElapsed;
}
else
{
uemit.particles[partNumber].m_alpha = 1.0 - (uemit.particles[partNumber].m_age - fadeIn) / (uemit.particles[partNumber].m_timeDie - fadeIn);
startScale = maxStartScale;
uemit.particles[partNumber].m_y += uemit.particles[partNumber].m_yVector * timeElapsed;
}
// the x direction is influenced by wind velocity
uemit.particles[partNumber].m_x += (uemit.particles[partNumber].m_xVector + uemit.m_windVelocity) * timeElapsed;
uemit.particles[partNumber].m_scale = 0.001 + startScale + uemit.particles[partNumber].m_age / 4000.0;
//printf( "x = %f y =%f\n", uemit.particles[partNumber].m_x, uemit.particles[partNumber].m_y);
/*printf("update m_speed: %f\n", emitter->m_speed);*/
*uemitter = uemit;
}
void initParticles(Particles *em, int x, int y) {
em->m_speed = 0.02;
em->m_alpha = 1.0;
em->m_windVelocity = 0.025;
em->m_dieRate = 0.95;
em->m_x = x;
em->m_y = y;
em->m_lastRender = getMilliCount();
for (int i = 0; i < PART_COUNT; i++)
{
em->particles[i].m_x = 0;
em->particles[i].m_canRegen = 1;
em->particles[i].m_age = i * 50000 * em->m_speed;
//Particle *cparticle = &emitter->particles[i];
startRand(&*em, &((*em).particles[i]), i);
//printf( "part = %d x = %f y =%f age = %u die = %u\n",i, em.particles[i].m_x, em.particles[i].m_y, em.particles[i].m_age, em.particles[i].m_timeDie);
}
}
char* createTag()
{
int i;
char *tag = malloc(sizeof(char)*GENERATOR_TAG_SIZE);
if (tag != NULL)
{
startRand();
for( i=0; i<GENERATOR_TAG_LENGTH; i++)
{
tag[i] = nextRand(2)==0?'0':'1';
}
tag[GENERATOR_TAG_LENGTH] = '\0';
}
else
{
#ifdef DEBUG
fprintf(stderr, "@Generator: Failed tag malloc\n");
#endif
}
return tag;
}
