Problem with simple physics

[the_raven]

Hi.

I thought this shouldn't be too difficult. But obviously it is. I have a bouncing ball (selfmade physics) that just won't stop bouncing. I added an event that should make it lie still if the downward speed is too low to bounce.

The next strange thing is: If you click the 'close window button' (the red button with the but move the mouse away from the x and then release the mouse button - it works!

I'm very confused and appreciate any help - thanks!

[netninja]

Timed events suck and you should never use them :P

On the line straight under the "Physix" comment (line 13 for me):
Ball.Internal Flag 0 is on
+ Every 00"-03 Seconds

Remove the line
+ Every 00"-03 Seconds

And it works perfectly. Great engine by the way.

[the_raven]

WOW thanks a lot! :grin:
It's working perfectly now. I don't exactly get why, but it's not that important if it works.

I must confess, though, that the physics are not completely my idea. I adapted and changed an old MMF1 tutorial for flying sparks.


Thanks again!

[netninja]

Well the simple answer is that timing events don't work well, because they aren't based on frames or something like that :P

So basically if you wanted something to happen less often that its supposed to, then you're better off making your own timer. i.e.

+ Always
add 1 to counter

+ If Counter >=6
Set counter to 0

+ Repeat while shift is pressed
+ Counter = 0
Shoot an object

This code would only allow the player to shoot a bullet every 1 in 6 frames. It's similar to if you had "Repeat while shift is pressed & Every 0.5 Seconds", however the code above uses frames to measure how often the player should be able to shoot, instead of a timer. Timers also run differently on different computers, and they also have problems when a computer is running the mmf game at a slower framerate than it was designed for.

So that's just an insight incase anybody else was wondering :P

[stuckboy]

I think the answer to your bouncing prob in general is to give the ball a lower elasticity.

Eg. Ball collides with floor:

-Set Y velocity to Y velocity * -1 * Elasticity

If elasticity = 1 the ball will bounce indefinitely
If elasticity = 0.5 the ball will lose half its momentum each time it bounces
If elasticity = 0 the ball will stop immediately when it hits the floor (this will probably cause errors in your physics unless you have a pretty sophisticated collision system running)

[Sphax]

To let your game work correctly check "run while resizing" option of your application.