fix parity for sand

1 files changed, 2 insertions, 2 deletions

diff --git a/src/sim/cell_sim/sim.rs b/src/sim/cell_sim/sim.rs
index 4b9f05f..253da8a 100644
--- a/src/sim/cell_sim/sim.rs
+++ b/src/sim/cell_sim/sim.rs
@@ -114,7 +114,9 @@ impl UpdateCtx<'_, '_, '_> {
                 && candidate_cell.material.def().density < self.material.density
             {
                 candidate_cell.reset_settled();
+                candidate_cell.match_parity(self.seqno + 1);
                 self.cell.reset_settled();
+                self.cell.match_parity(self.seqno + 1);
                 self.set_cell(0, 0, candidate_cell);
                 self.set_cell(dx, dy, *self.cell);
                 self.swapped = true;
@@ -145,8 +147,6 @@ pub fn sim_tick_chunk(chunks: &mut [Option<&mut Chunk>; 9], seqno: u64) {
                 if let Some(update) = material.sim_update
                     && cell.parity() == seqno_parity
                 {
-                    cell.flip_parity();
-
                     let mut update_ctx = UpdateCtx {
                         chunks,
                         seqno,