Quadtree test - 0.1

geometrian- x**.5 runs slower than math.sqrt(x) for me. Any sqrt is much slower than any square, so replacing it with a square where possible is better. Also, for most game applications, we don't need precision past a few places, so writing your own, sloppy sqrt function (and sin, cos, etc!) can pay off.

raubana- sqrt((x1-x2)**2 + (y1-yx)**2) < r --> (x1-x2)**2 + (y1-yx)**2 < r**2:
def collide(self, obj):
x=(self.pos[0]-obj.pos[0])
y=(self.pos[1]-obj.pos[1])
dist = x**2 + y**2
if dist <= (self.radius + obj.radius)**2 and dist!=0:
#we collided, act apon it

Excellent work!
math.sqrt(whatever) is slow. Try using whatever**0.5. Also, instead of whatever**2, try whatever*whatever.

Could you please post what the code now looks like? (Just the parts you changed)

I tried tweaking your code by squaring both sides of your collision test (to remove the slow sqrt operation), and the performance got way worse- my final framerate drops from ~23 to ~1, and it stops after 2 divisions instead of after 4. Out of context, python does the math almost twice as fast without the sqrt.

Do you know what's happening?

Sweet stuff! Right now collisions aren't my biggest slow-down, but I'll definitely be revisiting this when I get to doing more optimization.