Decreasing Digital timer error

[robind41618164]

Hi!

I've been trying to get a decreasing digital timer using expression. 

This is what I have so far:

slider = thisComp.layer("TIME").effect("Slider Control")("Slider")

sec = slider%60;

min = Math.floor(slider/60)%60;

function addZero(n) {

if (n < 10) return "0" + n else return n;

}

addZero(min) + ":" + addZero(sec)

In order te have it decrease I have linked it to a startpoint slider:

Math.floor(thisComp.layer("CONTROL").effect("TIME")("Slider") - time*1)

This way I can send it als a mogrt. and I dont have to worry about it anymore.

This all works fine until it reaches a value below zero, after that is starts to go negative in the decimals. 

For example: 0-1:0-3.

Are there any solutions to make it stop at 00:00?

[Dan Ebberts · Accepted solution]

I'm not sure where the startpoint slider fits in, but you should be able to just change your sec and min definitions, like this:

sec = Math.max(slider%60,0);
min = Math.max(Math.floor(slider/60)%60,0);

Also, if you want your addZero function to work with the JavaScript expression engine, you need to update it:

function addZero(n) {
  return (n < 10 ? "0" : "") + n;
}

[robind41618164]

That did the trick! Thank you.