Help! invert mask texture

Abdullah

I have a mask texture, pure black and white colors. Is there a way i can invert it in the material editor?

Obscura

The "one minus" expression, or multiplying it with -1.

Abdullah

Obscura wrote: »

The "one minus" expression, or multiplying it with -1.

thanks a lot one minus solved it. however multiplying with -1 gave me all black.

passerby

Just use the one minus node

TigerGD

Abdullah wrote: »

thanks a lot one minus solved it. however multiplying with -1 gave me all black.

Black is 0, so 0 * -1 = 0, and your black doesn't invert.
White is 1, so 1 * -1 = -1, and UE4 assumes 0.


You can try adding -1 and converting the output to absolute value.
0 + -1 = -1 (abs = 1)
1 + -1 = 0 (abs = 0)

I was looking for an alternative to OneMinus that I could parameterize. Make -1 a parameter value, and if you want to disable the inversion, you could change it to 0 at runtime.

feanix

material editor in unreal 4

Ramseus

TigerGD wrote: »

Black is 0, so 0 * -1 = 0, and your black doesn't invert.
White is 1, so 1 * -1 = -1, and UE4 assumes 0.


You can try adding -1 and converting the output to absolute value.
0 + -1 = -1 (abs = 1)
1 + -1 = 0 (abs = 0)

I was looking for an alternative to OneMinus that I could parameterize. Make -1 a parameter value, and if you want to disable the inversion, you could change it to 0 at runtime.
http://www.globaldonimation.com/images/Rocket_Smoke_graph.png

I'm usually too simple minded to think of using absolute value, I would just do
X * -1 + 1

or if it's greyscale plug it into the alpha of a lerp with the default 1 and 0 values flipped, that's a real easy inversion that doesn't involve minus one.