gravitize_planets: Fix approximation from the gravity equation

This was needed when there was no collosions between the planets and
the planets could "explode" when they got too close to each others.

Signed-off-by: Timo Kokkonen <kaapeli@itanic.dy.fi>

diff --git a/planet.c b/planet.c
index 9e44e099e623c831ee41d0da54319b1ad10032b4..166d8400f1c3269a2640850f21b8e8fdc16bcd35 100644 (file)
--- a/planet.c
+++ b/planet.c
@@ -95,7 +95,7 @@ int gravitize_planets(struct planet *a, struct planet *b, const double time)
 
        vector_div(&distance, dist, &distance);
 
-       f = a->mass * b->mass / (dist * dist + 5) * time;
+       f = a->mass * b->mass / (dist * dist) * time;
 
        acc = f / b->mass;
        vector_scale(&distance, acc, &sum);