Get direction and speed (Please help)

[Captain_Harris]

I have a player that move left and right. it is controlled by - always set x position to x mouse.

1.how can i get the direction of the player.

2. how can i get the speed of the player.

( i can not use the 8 direction movement, because i can not control it without buttons )

[tompa]

One solution is to measure distance between 2 points within a constant timeframe.

When these points exist in a system, it's viable to calculate speed (from distance in time) and angle.

[Captain_Harris]

Can you give a example please.

[tompa]

Yes, this widget uses a constant timeframe.


A similar solution is to save Xmouse & Ymouse in variables every 3ms

Velocity example (Euclidean)
A = Mouse position 3ms ago
B = Mouse position now
E = Velocity

E = sqr(((A.x - B.x) pow 2) + ((A.y - B.y) pow 2))


Angle between 2 points
A = Mouse position 3ms ago
B = Mouse position now
C = Angle

C = ATan2(A.y - B.y, B.x - A.x)




...I know, I post these formulas often.

[Captain_Harris]

I do not know if my intelligence is sufficient for. but i'll try to work with this. Thank you.
if anyone knows an easier way, please help.

one thing. how can i get xmouse 3ms ago ?

[tompa]

There's a clock inside conditions.

It's enabling conditions to run "every" x time.

[Captain_Harris]

Thank you

[Decoamorim]

Tompa,

Do i have to use this expression on a value?

For an exemple, i want to a motion set of events happens when the object X is at 50 pixels away from the object Y.

So i used "COMPARE TO GENERAL VALUES" , like this:


Sqr(X( "Fidao xbox" )-X( "enemy" ))*(X( "Fidao xbox" )-X( "enemy" ))+(Y( "Fidao xbox" )-Y( "enemy" ))*(Y( "Fidao xbox" )-Y( "enemy" ))

greater or equal

50

Than told the object enemy to walk left. But did not work.
Only works when i said that the expression is different from ZERO.

Why is that? What am i doing wrong here?

I want to (exemple) at 50 pixels the enemy walks to the object, than when its close, lower than 50, starts a random atack that i created.

[AyreGuitar]

Decoamorim - Compare to general values won't work on multiple objects (eg your enemy objects). Instead, try setting an Alt Val in the enemy objects to your calculation eg:

Always:
Alt Val A("enemy")=Sqr(X( "Fidao xbox" )-X( "enemy" ))*(X( "Fidao xbox" )-X( "enemy" ))+(Y( "Fidao xbox" )-Y( "enemy" ))*(Y( "Fidao xbox" )-Y( "enemy" ))

If Alt A("enemy")>=50
(Do your actions here)

Hope that helps!

[tompa]

I looked at your function decoa. Your parentheses are just placed wrong. Square root should apply over the whole Euclidean formula.
If the formula looks messy you can use pow2 instead of multiplying terms. In MMF2 Developer the pow2 = ^2.

example
(x + y) * (x + y) = (x + y) pow2


added
if you plan to have more than one entity (enemy) you should follow guitars instructions.