OTOY Forums

Perhaps I don't have my thinking head on today but I am unable to work out how to apply decals.

I thought that it would be easy using a alpha image but when I do all I get is white areas where the PNG was not transparent and the correct transparency where I want it. I would like a bit more than just a white decal.

I would post an image of what I am trying to achieve but it would appear as if there is something wrong with the server at the moment.

Are you using the alpha as the mix value for your decal and model?

I knew that I didn't have my thinking head on. Thanks for giving me the jolt that I required.

This got me to thinking. If we load up a .PNG with transparency, wouldn't it be awesome if that image node had two output pins, one for image and one for alpha? That way, you could load up the image, attach image pin to your mix node and the alpha pin to mix amount. That way you only have to load one texture instead of two. Maybe this could help people cut down on amount of textures in their scenes???

sounds like a good idea. With the limited number of images that can be loaded, reducing the number can only be good.

+1

kavorka wrote:This got me to thinking. If we load up a .PNG with transparency, wouldn't it be awesome if that image node had two output pins, one for image and one for alpha? That way, you could load up the image, attach image pin to your mix node and the alpha pin to mix amount. That way you only have to load one texture instead of two. Maybe this could help people cut down on amount of textures in their scenes???

Try loading the exact same png (with alpha) as an image as well as alpha image, you will notice that octane is smart and only one texture slot is used

thanks
Chris.

FooZe wrote:

kavorka wrote:This got me to thinking. If we load up a .PNG with transparency, wouldn't it be awesome if that image node had two output pins, one for image and one for alpha? That way, you could load up the image, attach image pin to your mix node and the alpha pin to mix amount. That way you only have to load one texture instead of two. Maybe this could help people cut down on amount of textures in their scenes???

Try loading the exact same png (with alpha) as an image as well as alpha image, you will notice that octane is smart and only one texture slot is used

thanks
Chris.

Wont that create a greyscale alpha using the images color values? What I want is for it to use the alpha of the image, not the image as an alpha.

If you want to add for example a yellow decal on a red car, just use a different material for the area with decal and area without decal.

Use an image with red margins around your decal, and apply a material with the exact same red color for the areas without decal. For my own, I use a 2x2 pixels image of the same color as margins : it gives more accurate matching colors than using a procedural color. procedural color is usable but requires more tweakings.

I used this method for most of the texture of my Routemaster bus :

http://3d-synthesis.com/53-LondonScene1970.html

The washed pink areas on the attached texture example are the shapes of the UV mapped faces receiving details of the decal texture.

They are not washed out in the real texture. This is just to make it more obvious as an example.

I hope this is understandable.

I was thinking the same thing recently. I work in C4D, and when i use an Alpha there, it's used as a transparency for the color (diffuse) channel. If i use an Alpha in Octane it's used as an Alpha for the mesh and not the diffuse channel. How can I use an Alpha just on the diffuse instead of the mesh. I've tried different formats (PSD, TIFF, PNG), but couldn't get it done.