phase-shifted PWM

i'm trying make program quite simply, shifts phase of pwm numbers.
so have 2 variables, var1 , var2.
var1 moving , down between 0 , 255. want var2 30 degrees out of phase of this,
so when:
var1 = 0
var2 = 64

var 1 = 128
var2 = 192

but also,
var1 = 255
var2 = 192

now getting maths beyond small brain's capability, seeing didn't maths past gcse.
anyone care lend hand? or brain, rather?

greetings,

doesn't simple work:

code: [select]

setup() {
   int var1 = 0;
   int var2 = 64;
}

loop () {
  var1 = (var1 + 1) % 256;
  var2 = (var2 + 1) % 256;
}


the variables start off fixed phase difference, , long incremented together, , wrap-around @ same point, stay in sync.

regards,
david

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