From 6c3093cabf7cb16cf95eba2b7ea5bbb5ed33c863 Mon Sep 17 00:00:00 2001
From: Simon Robertshaw <simon@hardwired.org.uk>
Date: Sat, 25 Jun 2011 17:40:35 +0100
Subject: [PATCH] Hot air rises [Experimental]

---
 src/air.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/air.c b/src/air.c
index c65e1a0c4..5f45662be 100644
--- a/src/air.c
+++ b/src/air.c
@@ -108,6 +108,12 @@ void update_airh(void)
 				dh += AIR_VADV*(1.0f-tx)*ty*hv[j+1][i];
 				dh += AIR_VADV*tx*ty*hv[j+1][i+1];
 			}
+			if(!gravityMode){ //Vertical gravity only for the time being
+				float airdiff = dh-hv[y][x];
+				pv[y][x] += airdiff/5000.0f;
+				if(airdiff>0)	
+					vy[y][x] -= airdiff/5000.0f;
+			}
 			ohv[y][x] = dh;
 		}
 	}