how can I make a curveball (baseball) ?

gooner

1) i have an actor spawn from top of screen with negative Y linear velocity for the baseball
2) this ball is "pitched" downward toward Y pos 0 (bottom of screen)
.. this works fine

i would now like the ball to start curving as it travels downward toward "home plate"

i've tried change X pos and interpolate X pos but nothing happens with the incorrect way i am attempting this.

any idea of what i could change to create the effect of curving last second at home plate?

thanks! and always appreciate any feedback.

Socks

_i would now like the ball to start curving . . . _

This could mean a whole bunch of things, can you be any more specific ? Maybe a quick sketch of the ball's path would help.

Hopscotch

@ellison

since you use linear velocity, you can do the same in the x direction.

constrain: self.Motion.Linear Velocity.X = 0.01*pow(1.012,(sceneheight-self.position.Y))

Play around with the values for the right feel.

Changing the first (0.01) value sets how soon or how late the curving starts.
The second (1.012) changes the "strength" of the curve.

Be careful, small changes have a drastic effect.

gooner

@Socks said:
_i would now like the ball to start curving . . . _

This could mean a whole bunch of things, can you be any more specific ? Maybe a quick sketch of the ball's path would help.

best image i can think of would be the atari logo ... the three lines would show the path of three different pitches (curve left, straight, curve right)

i am trying to do curve right and curve left

thanks!

gooner

@Hopscotch said:
@ellison

since you use linear velocity, you can do the same in the x direction.

constrain: self.Motion.Linear Velocity.X = 0.01*pow(1.012,(sceneheight-self.position.Y))

Play around with the values for the right feel.

Changing the first (0.01) value sets how soon or how late the curving starts.
The second (1.012) changes the "strength" of the curve.

Be careful, small changes have a drastic effect.

wow, this is impressive, thanks!!!

i was able to get the curve to happen but it starts to curve too late and the arc is too drastic, when i change the values, it doesn't curve at all (so yeah i messed something up)

i would like the ball to start curving around halfway down and to end up in a set area (between center of screen - 100 and center of screen +100) which is X Pos 284 thru 484. Would there be a change to the formula if I know i want it to end up between X Pos 284 and 484?

Hopscotch

@ellison

did you see the project I posted here?

http://forums.gamesalad.com/discussion/comment/589837/#Comment_589837

You can visually play around with the curve to get the values. In your case just swap the X and Y values to get the vertical effect.

Once you have the values you want, you can even introduce a bit of randomness on the B value.

To randomly change the direction between left and right, multiply the A value by (random(0,1)*2-1)

gooner

@Hopscotch said:
@ellison

did you see the project I posted here?

http://forums.gamesalad.com/discussion/comment/589837/#Comment_589837

You can visually play around with the curve to get the values. In your case just swap the X and Y values to get the vertical effect.

Once you have the values you want, you can even introduce a bit of randomness on the B value.

To randomly change the direction between left and right, multiply the A value by (random(0,1)*2-1)

great! thank you... i will be trying it out later

gooner

@Hopscotch ... OK I tried this but I still am not getting it yet.

I downloaded project from the thread and adjusted the points to get the curve I need.

point A was around .14
point B was better around 1.01 or less

I have Position X = 384+point A * pow(point B, position Y - 384)

This is making it start out wide and curve inward and go straight down to bottom center of the screen.

I do not understand it enough yet to make changes and/or figure out which part I have reversed improperly. By looking at my example can you see anything I need to move around or flip?

Thanks!

Hopscotch

@ellison try this project.

It is probably close to what you want, also in portrait mode.

In the ball actor is a "Spread" attribute which you can play with, to adjust the curve.

gooner

Thank you very much ... I was able to use this and get the desired results. Really appreciate it (and the spread attribute so I can adjust the curve).

Hopscotch

My pleasure @ellison