void LLViewerPartGroup::updateParticles(const F32 lastdt)
{
LLMemType mt(LLMemType::MTYPE_PARTICLES);
F32 dt;
LLVector3 gravity(0.f, 0.f, GRAVITY);
LLViewerPartSim::checkParticleCount(mParticles.size());
LLViewerRegion *regionp = getRegion();
S32 end = (S32) mParticles.size();
for (S32 i = 0 ; i < (S32)mParticles.size();)
{
LLVector3 a(0.f, 0.f, 0.f);
LLViewerPart* part = mParticles[i] ;
dt = lastdt + mSkippedTime - part->mSkipOffset;
part->mSkipOffset = 0.f;
// Update current time
const F32 cur_time = part->mLastUpdateTime + dt;
const F32 frac = cur_time / part->mMaxAge;
// "Drift" the object based on the source object
if (part->mFlags & LLPartData::LL_PART_FOLLOW_SRC_MASK)
{
part->mPosAgent = part->mPartSourcep->mPosAgent;
part->mPosAgent += part->mPosOffset;
}
// Do a custom callback if we have one...
if (part->mVPCallback)
{
(*part->mVPCallback)(*part, dt);
}
if (part->mFlags & LLPartData::LL_PART_WIND_MASK)
{
LLVector3 tempVel(part->mVelocity);
part->mVelocity *= 1.f - 0.1f*dt;
part->mVelocity += 0.1f*dt*regionp->mWind.getVelocity(regionp->getPosRegionFromAgent(part->mPosAgent));
}
// Now do interpolation towards a target
if (part->mFlags & LLPartData::LL_PART_TARGET_POS_MASK)
{
F32 remaining = part->mMaxAge - part->mLastUpdateTime;
F32 step = dt / remaining;
step = llclamp(step, 0.f, 0.1f);
step *= 5.f;
// we want a velocity that will result in reaching the target in the
// Interpolate towards the target.
LLVector3 delta_pos = part->mPartSourcep->mTargetPosAgent - part->mPosAgent;
delta_pos /= remaining;
part->mVelocity *= (1.f - step);
part->mVelocity += step*delta_pos;
}
if (part->mFlags & LLPartData::LL_PART_TARGET_LINEAR_MASK)
{
LLVector3 delta_pos = part->mPartSourcep->mTargetPosAgent - part->mPartSourcep->mPosAgent;
part->mPosAgent = part->mPartSourcep->mPosAgent;
part->mPosAgent += frac*delta_pos;
part->mVelocity = delta_pos;
}
else
{
// Do velocity interpolation
part->mPosAgent += dt*part->mVelocity;
part->mPosAgent += 0.5f*dt*dt*part->mAccel;
part->mVelocity += part->mAccel*dt;
}
// Do a bounce test
if (part->mFlags & LLPartData::LL_PART_BOUNCE_MASK)
{
// Need to do point vs. plane check...
// For now, just check relative to object height...
F32 dz = part->mPosAgent.mV[VZ] - part->mPartSourcep->mPosAgent.mV[VZ];
if (dz < 0)
{
part->mPosAgent.mV[VZ] += -2.f*dz;
part->mVelocity.mV[VZ] *= -0.75f;
}
}
// Reset the offset from the source position
if (part->mFlags & LLPartData::LL_PART_FOLLOW_SRC_MASK)
{
part->mPosOffset = part->mPosAgent;
part->mPosOffset -= part->mPartSourcep->mPosAgent;
}
// Do color interpolation
if (part->mFlags & LLPartData::LL_PART_INTERP_COLOR_MASK)
{
part->mColor.setVec(part->mStartColor);
// note: LLColor4's v%k means multiply-alpha-only,
// LLColor4's v*k means multiply-rgb-only
part->mColor *= 1.f - frac; // rgb*k
part->mColor %= 1.f - frac; // alpha*k
part->mColor += frac%(frac*part->mEndColor); // rgb,alpha
}
// Do scale interpolation
if (part->mFlags & LLPartData::LL_PART_INTERP_SCALE_MASK)
{
part->mScale.setVec(part->mStartScale);
part->mScale *= 1.f - frac;
part->mScale += frac*part->mEndScale;
}
// Set the last update time to now.
part->mLastUpdateTime = cur_time;
// Kill dead particles (either flagged dead, or too old)
if ((part->mLastUpdateTime > part->mMaxAge) || (LLViewerPart::LL_PART_DEAD_MASK == part->mFlags))
{
mParticles[i] = mParticles.back() ;
mParticles.pop_back() ;
delete part ;
}
else
{
F32 desired_size = calc_desired_size(part->mPosAgent, part->mScale);
if (!posInGroup(part->mPosAgent, desired_size))
{
// Transfer particles between groups
LLViewerPartSim::getInstance()->put(part) ;
mParticles[i] = mParticles.back() ;
mParticles.pop_back() ;
}
else
{
i++ ;
}
}
}
S32 removed = end - (S32)mParticles.size();
if (removed > 0)
{
// we removed one or more particles, so flag this group for update
if (mVOPartGroupp.notNull())
{
gPipeline.markRebuild(mVOPartGroupp->mDrawable, LLDrawable::REBUILD_ALL, TRUE);
}
LLViewerPartSim::decPartCount(removed);
}
// Kill the viewer object if this particle group is empty
if (mParticles.empty())
{
gObjectList.killObject(mVOPartGroupp);
mVOPartGroupp = NULL;
}
LLViewerPartSim::checkParticleCount() ;
}
