I'n almost any indevor, even not graphic, this is usefull:

#define within(v,x,y) (((v <= y)&&(v >= x)) ? true : false)

Wanted to post that in 'Programmer "Prognography"', but they killed it?! It had potential, it just needed time...

To anybody this helps, Thanks for taking a chance and trying it, and You're welcome for the help! SPH