draw.RoundedBox going from left to right instead of right to left?

Hello. I have an issue that’s quite difficult to explain.

Okay, so let’s say you set the draw.roundedbox’s width to the player’s gun’s ammo. Everytime you shoot, it decreases in length, but it decreases from the right, and I want to make it decrease from the left. How would I do this?

What you’d need to do would be something like:

[lua]
local LENGTH = 100

draw.RoundedBox( 5, ( 500 - LENGTH ), 500, LENGTH, 500, color_white )
[/lua]