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EagleWing
10-26-2010, 04:03 PM
Hi Everyone,

I have a very strange problem with lightwave 9.6 and I can't for the life of me figure out why it's doing what it's doing....perhaps someone can help?..

I am trying to assign an image as a transparency map.
The image is a high res image of the earth's clouds.
now as you can gather, given the image, the clouds are white and the rest is black.
My current knowledge for transparency maps is that
Black is 100% transparent and
White is 0% transparent correct?

If you view the first attachment (1.jpg) you'll see the image i'm applying on the left and that for some reason after adding the image it's making the white areas transparent and not the black? Why?

the second attachment (2.jpg) shows that I have to click the Invert layer button in order to get the desired effect.

Also as a side note why is it automatically applying the image as a mask when I've still got the blending mode as 'normal'?

Many thanks for any valued input,
EW.

Danner
10-26-2010, 04:22 PM
white is 100% black 0%

EagleWing
10-26-2010, 04:28 PM
Thanks Danner, so I've been thinking the wrong way round? white is actually removed?
has it always been like this because I'm sure it used to be black was removed?

Thanks.

Danner
10-26-2010, 04:30 PM
it has always been like this. makes sense if you think about it, All other maps you apply act that way.
White on an diffuse channel is 100% diffusse black is 0% diffuse, white on reflectivity is 100% and so on.

EagleWing
10-26-2010, 04:42 PM
This is a scene I created back before version 9.5, you'll notice that the alpha map is using the black for the transparency here, ok it's in the colour layer but still....I am confused why in one case white is transparent and in another black is transparent.

Danner
10-26-2010, 04:53 PM
it's because the transfer mode is set to Alpha, and alpha works the other way around than transparency. Think of it this way. Apha is actually the opposite of transparency. The more alpha values you have, the more solid it is. On the other hand, transparency get stronger as you up the values.

If you want to change the alpha values of a surface you can do so. (it goes from 0 to 255 instead of percetanges) the higher the value the more solid it is.

If you up the transparency, it is more transparent.

EagleWing
10-26-2010, 05:02 PM
Ok, so that I'm clear...alpha blending mode uses black to remove pixels and white to keep.
whereas the transparency layer and every other texture layer uses white to remove pixels if you dont have alpha blending mode selected?

Many thanks for your help Danner I really appreciate it. I'm just getting back into Lightwave after being away from it for 3 years.

Danner
10-26-2010, 05:06 PM
and every other texture layer uses white to remove pixels if you dont have alpha blending mode selected?



Every other texture layer uses white to increase it's channels strenght not to remove pixels.

EagleWing
10-26-2010, 05:10 PM
ah ok I think I understand. only an alpha blending mode therefore initiates the removal of pixels, normal blending mode in a layer just defines the pixels strength.

gotcha.

ok Thanks for your input again.
EW

Danner
10-26-2010, 05:23 PM
I think you are getting it. But "removal of pixels" is confusing while thinkind about alphas =). it's more like "each pixel's brightness value determines the opacity (from 0-255)

EagleWing
10-26-2010, 05:25 PM
gotcha. ;-)

Thanks Danner the pints are on me :)

zardoz
10-27-2010, 04:40 AM
I guess the problem might be related to what other softwares call it. In max it's called an opacity map, so white is opaque and black is transparent. In lightwave it's a transparency map, so white is transparent and black is opaque. The alpha acts like an opacity map.