Hello All,

I've searched but failed to find an answer to this question. Or probably I'm just not understanding what I've found.

I have an automated pipeline that takes in a parameterized texture. Some of these textures have alpha channels, but I need to make sure there is no transparency when I apply them to the geometry. I need to reveal the texture RGB colors that are hidden by the transparency.

I've tried every likely seeming combination of settings on the principled shader node that I can find in Houdini 20.5, but I haven't found the right settings I guess. I've tried messing with transparency under the Surface tab as well as settings under the Opacity tab. I'm importing the texture itself with the "Use Texture" toggle on the Textures tab.

Below are screenshots of the box I'm applying the texture to (just one triangle of the box), the texture itself, and the texture if I edit it in gimp to have an opaque alpha channel. I won't be able to edit the textures coming through this pipeline externally, though, and I feel sure I'm just missing how to do this in Houdini.

Apologies if this question is frustratingly ignorant!

Hi,

Am I right saying basically anything on this texture can be seen until you choose to apply its alpha which will obviously
make any existing rgb values transparent.

If so attached a basic hip with a transparency control using a standard materialX shader using a png file.

Does this help or am I way off? (wouldn't be the first time haha)


Cheers!

@EZiniT -- Thank you so much for this. I will go check it out. For some reason I'm no longer getting notifications of replies to my posts, or I would have thanked you weeks ago!

Best wishes,
Mary

Alas, @EZiniT, the hip is getting a seg fault when I try to focus on it in the view port. I'll see if I can figure this out, but if you see an obvious reason for it, please let me know! I'm using version 20.5 on Fedora 41 -- not sure that that should make any difference.

Thanks again,
Mary

No idea what would be causing a segmentation fault, although I do tend to use the daily builds a lot, maybe
a new update it doesn't like. is this file any better?

Thanks again, @EZInit. I very much appreciate the time it took to try to help me even if for some reason it's not working on my side :-( In the end, I clumsily solved the problem by loading the image in stbi, changing its alpha to 1.0 on all the pixels, and rewriting the image. Ghastly of course, but it works...

I'll use a separate post to ask a related question about one of the shader parameters I thought would do the trick but doesn't.

Thank you again!
Mary

I would have thought with almost 1000 views someone would say "hey yeah I'm also having a problem loading the scene too, or not"
My Houdini install could have an issue or perhaps yours, either way would have been helpful to know huh.


Glad you got it solved