Fine sand runs to its end on Fast
Fast merges the closest pairs of parcels only where a grid cell would otherwise run out of room, so the 2 mm Sand pile on a part runs to its end. Everything else is unchanged.
Limits
A sand pour onto a part can still stop at 2 and 3 mm Custom sizes: a continuous stream packs the sand under it faster than merging pairs can make room. Switch to Accurate to run it through.
Where the sand spreads thin, the Surface view can show small gaps; filling them is the next step for Fast.
A merged parcel holds at most two of the original parcels, so a crowded spot never loses more than half its particles.
Everything in this release
Improved
- The Sand pile on a part demo at a 2 mm Custom size runs to its end on Fast instead of stopping after about 0.27 s with "too many particles crowded into one grid cell". Where a grid cell would otherwise run out of room, Fast merges the closest pairs of parcels into one, keeping their mass and momentum exactly. In that run about 280 of its 115,000 sand parcels merge.
- Runs that never come near filling the grid's storage are unchanged, bit for bit: the water demos, coarser sand and the other demos at their default sizes give the same results as before.
- A sand pour onto a part runs longer before it stops at 2 and 3 mm Custom sizes, and runs to its end at 4 mm.
- In the Particles view a merged parcel is drawn at its true size, and Details › Particles says how many pairs were merged.
Other improvements
- Fine sand runs to its end on Fast: the Sand pile on a part demo at a 2 mm Custom size no longer stops with "too many particles crowded into one grid cell". Fast merges the closest pairs of parcels only where they would otherwise overflow the grid's storage, keeping their mass and momentum exactly; runs that never come near filling it are unchanged. Merged parcels are drawn at their true size. A sand pour onto a part runs longer before it stops at 2 and 3 mm, and runs to its end at 4 mm.
