--- a/skaapsteker/physics.py	Mon Apr 04 00:14:02 2011 +0200
+++ b/skaapsteker/physics.py	Mon Apr 04 00:42:33 2011 +0200
@@ -14,8 +14,8 @@
     mobile = True # whether the velocity may be non-zero
     gravitates = True # whether gravity applies to the sprite
 
-    terminal_velocity = (100.0, 100.0) # maximum horizontal and vertial speeds
-    bounce_factor = (0.9, 0.9) # bounce factor
+    terminal_velocity = (300.0, 300.0) # maximum horizontal and vertial speeds
+    bounce_factor = (0.98, 1.05) # bounce factor
 
     def __init__(self, *args, **kwargs):
         super(Sprite, self).__init__(*args, **kwargs)
@@ -56,21 +56,35 @@
 
     def collide_immobile(self, immobile):
         print "Collided with immobile:", self, immobile
+        if not self.rect.colliderect(immobile.rect):
+            print "  Collision avoived!"
+            return
+
         v_x, v_y = self.velocity
         clip = self.rect.clip(immobile.rect)
-        frac_x = clip.width / abs(v_x) if abs(v_x) > EPSILON else 0.0
-        frac_y = clip.height / abs(v_y) if abs(v_y) > EPSILON else 0.0
-        frac = max(frac_x, frac_y)
-        b_x = -v_x * self.bounce_factor[0] * immobile.bounce_factor[0]
-        b_y = -v_y * self.bounce_factor[1] * immobile.bounce_factor[1]
+        MAX_DT = 0.1
+        frac_x = clip.width / abs(v_x) if abs(v_x) > EPSILON else MAX_DT
+        frac_y = clip.height / abs(v_y) if abs(v_y) > EPSILON else MAX_DT
+
+        if frac_x > frac_y:
+            # collision in y
+            frac = frac_y
+            b_y = -v_y * self.bounce_factor[1] * immobile.bounce_factor[1]
+            b_x = v_x
+        else:
+            # collision in x
+            frac = frac_x
+            b_x = -v_x * self.bounce_factor[0] * immobile.bounce_factor[0]
+            b_y = v_y
+
         self.velocity = (-v_x, -v_y)
-        self.deltap(frac)
+        self.deltap(frac * 1.1)
         self.velocity = (b_x, b_y)
 
 
 class World(object):
 
-    GRAVITY = 9.8 # m/s^2
+    GRAVITY = 9.8 * 20.0 # m/s^2
 
     def __init__(self):
         self._all = pygame.sprite.LayeredUpdates()
@@ -99,7 +113,7 @@
         self._last_time, dt = now, now - self._last_time
 
         # gravity
-        dv = (0, self.GRAVITY * dt)
+        dv = (-self.GRAVITY * 0.5 * dt, self.GRAVITY * dt)
         for sprite in self._gravitators:
             sprite.deltav(dv)