Basic math help needed

tatiang

I want to have an actor that constrains self.alpha to a number based on another actor's self.position.y so that if Y is large, alpha is small and if Y is small, alpha is large. For example, if Y is 900 then alpha is .4; if Y is 450 then alpha is .7; if Y is 0 alpha is 1.

My brain is broken. Please help.

mynameisace

Just knocked this up for you:

http://mynameisace.com/files/Alpha-Alphalfa.gameproj.zip

I'm no doctor, but I hope this fixes your brain.

Ace

JohnPapiomitis

Just threw this together for you. Is this what your after?

http://www.mediafire.com/?vprsasx7c9axq3j

tatiang

Awesome help guys, thanks! Each of you gave me a useful demo, but Ace solved the problem with inverted values. It was a simple percentage (distance of the actor from the maximum possible height divided by the maximum possible height), but I couldn't wrap my April Fools' affected mind around. I blame Lego.

self.alpha=(otheractor.position.y-game.maxY)/(game.minY-game.maxY)

JohnPapiomitis

Yep theres many usueally many differnt ways to do thing in gs. By changing the dividing factor in mine you can achieve it at any distance. But @mynameisace used set attributes and fancy colors so this one goes to him

mynameisace

Fancy colours always win... Remember that and you will never lose

Ace

tatiang

Yep theres many usueally many differnt ways to do thing in gs. By changing the dividing factor in mine you can achieve it at any distance. But @mynameisace used set attributes and fancy colors so this one goes to him

Well actually I meant that your demo increased the alpha as the actor went higher, whereas ace's demo increased the alpha as the actor went lower (which is what I wanted). Yours is more of a 1:1 ratio and his is a percentage of the total height.