1 files changed, 62 insertions, 3 deletions

diff --git a/linden/indra/newview/llviewerpartsource.cpp b/linden/indra/newview/llviewerpartsource.cpp
index 6c93e75..f54495a 100644
--- a/linden/indra/newview/llviewerpartsource.cpp
+++ b/linden/indra/newview/llviewerpartsource.cpp
@@ -36,6 +36,7 @@
 
 #include "llagent.h"
 #include "lldrawable.h"
+#include "llviewercamera.h"
 #include "llviewerimagelist.h"
 #include "llviewerobject.h"
 #include "llviewerobjectlist.h"
@@ -53,6 +54,8 @@ LLViewerPartSource::LLViewerPartSource(const U32 type) :
         mIsSuspended = FALSE;
         static U32 id_seed = 0;
         mID = ++id_seed;
+
+        mDelay = 0 ;
 }
 
 void LLViewerPartSource::setDead()
@@ -79,6 +82,10 @@ LLUUID LLViewerPartSource::getImageUUID() const
         }
         return LLUUID::null;
 }
+void LLViewerPartSource::setStart()
+{
+        mDelay = 99 ;
+}
 
 LLViewerPartSourceScript::LLViewerPartSourceScript(LLViewerObject *source_objp) :
         LLViewerPartSource(LL_PART_SOURCE_SCRIPT)
@@ -111,6 +118,8 @@ void LLViewerPartSourceScript::update(const F32 dt)
         LLMemType mt(LLMemType::MTYPE_PARTICLES);
         F32 old_update_time = mLastUpdateTime;
         mLastUpdateTime += dt;
+
+        F32 ref_rate_travelspeed = llmin(gWorldPointer->mPartSim.getRefRate(), 1.f);
         
         F32 dt_update = mLastUpdateTime - mLastPartTime;
 
@@ -199,21 +208,71 @@ void LLViewerPartSourceScript::update(const F32 dt)
                         // No angular velocity.  Reset our rotation.
                         mRotation.setQuat(0, 0, 0);
                 }
-
+                
                 if (gWorldPointer->mPartSim.aboveParticleLimit())
                 {
                         // Don't bother doing any more updates if we're above the particle limit,
                         // just give up.
                         mLastPartTime = mLastUpdateTime;
+            break;
+
+                }
+                
+                // find the greatest length that the shortest side of a system
+                // particle is expected to have
+                F32 max_short_side =
+                        llmax(
+                              llmax(llmin(mPartSysData.mPartData.mStartScale[0],
+                                          mPartSysData.mPartData.mStartScale[1]),
+                                    llmin(mPartSysData.mPartData.mEndScale[0],
+                                          mPartSysData.mPartData.mEndScale[1])),
+                              llmin((mPartSysData.mPartData.mStartScale[0]
+                                     + mPartSysData.mPartData.mEndScale[0])/2,
+                                    (mPartSysData.mPartData.mStartScale[1]
+                                     + mPartSysData.mPartData.mEndScale[1])/2));
+                
+                F32 pixel_meter_ratio = gCamera->getPixelMeterRatio();
+
+                // Maximum distance at which spawned particles will be viewable
+                F32 max_dist = max_short_side * pixel_meter_ratio; 
+
+                if (max_dist < 0.25f)
+                {
+                        // < 1 pixel wide at a distance of >=25cm.  Particles
+                        // this tiny are useless and mostly spawned by buggy
+                        // sources
+                        mLastPartTime = mLastUpdateTime;
                         break;
                 }
 
+                // Distance from camera
+                F32 dist = (mPosAgent - gCamera->getOrigin()).magVec();
+
+                // Particle size vs distance vs maxage throttling
+
+                F32 limited_rate=0.f;
+                if (dist - max_dist > 0.f)
+                {
+                        if((dist - max_dist) * ref_rate_travelspeed > mPartSysData.mPartData.mMaxAge - 0.2f )
+                        {
+                                // You need to travel faster than 1 divided by reference rate m/s directly towards these particles to see them at least 0.2s
+                                mLastPartTime = mLastUpdateTime;
+                                break;
+                        }
+                        limited_rate = ((dist - max_dist) * ref_rate_travelspeed) / mPartSysData.mPartData.mMaxAge;
+                }
+                
+                if(mDelay)
+                {
+                        limited_rate = llmax(limited_rate, 0.01f * mDelay--) ;
+                }
+
                 S32 i;
                 for (i = 0; i < mPartSysData.mBurstPartCount; i++)
                 {
-                        if (!gWorldPointer->mPartSim.shouldAddPart())
+                        if (ll_frand() < llmax(1.0f - gWorldPointer->mPartSim.getBurstRate(), limited_rate))
                         {
-                                // Particle simulation says we have too many particles, skip all this
+                                // Limit particle generation
                                 continue;
                         }