Update version 1.0.13 — icpaint Steam update #4678519

Drawn content now looks sharper while running the "Liquify filter" and "Retouch filter". Previously, when I zoomed in, it was a little blurry. If you painted and executed "Undo" immediately after creating a canvas, the wrong "Undo" might be executed. Fixed this. Commands such as "Transform" could sometimes darken the color of semi-transparent pixels. Fixed this. As a result, adjusting the brightness parameter with the "Radial blur" filter now looks different than before. The calculation formula for the "Noise" filter was incorrect, so it has been corrected. As a result, the translucent pixels look a little different than before.