Alpha Images

[thearshadnadeem]

hi 

i am trying to import a fence model from maya i have textured it it has transperancy channel i imported this model with various pic formats like png,tiff,targa but its still show the tranperancy as a black texture pls help me out how can i import models which has tranperancy channel or alpha channel pls help

thanks

Arshad Nadeem.

[frank.delise · Accepted solution]

.png or .tga is fine,

Just make sure your parent material is standard_masked and use color map alpha is checked.

If you compress the image in Stingray, make sure its DTX5, DTX1 does not support alpha.

[thearshadnadeem]

i tried like u said so i am sending these images i think i m making some mistake it's not working with me ?

[dan.matlack]

Hello, my guess here is that your color image does not have an alpha channel. You can do this by using png and leaving the parts you want not rendered empty or you can add the alpha channel mask to a tga and import. 

PNG

TGA

[mcm85_85]

I have tried to use an image with alpha channel but white borders appear when I rotate the 3D object.

[dan.matlack]

I am looking into this now and will get back to you.

[mcm85_85]

Thank you!

I forgot to mention that I set Color Map - Filter mode = Point

[lumonix]

Hi,

I think what is going on is that you have partially transparent pixels in the image around the edges.

In the image Dan sent me, there are partially transparent pixels anyway.

That is how PNG handles alpha masks in Photoshop, but those partially transparent pixels become grey when importing the PNG

For your mask, you want to remove those in Photoshop and only have black or white pixels.

Or, if that is hard, you can increase the Opacity Threshold of the material a little to remove more of the pixels.

[dan.matlack]

Kees is correct. I think a good solution for your issue would be create a better photoshop image. See attached example at a higher resolution with harder edges. In the image below, you can see your star in the back ground with a newer one I created on top. Those 'gray' and 'softer' edges at a lower resolution will definitely cause the white you see on your edges in engine. Try the attached image and see how it goes.

[mcm85_85]

Yes, it solve the problem but I'm using a texture atlas.

Can I reduce the problem by using two Color Map, one for base color (Filter mode = Point) and one for opacity (Filter mode = Anisotropic)?

[dan.matlack]

I'm not sure how that will work out as any different if your resolution is still fairly low. With the pngs you can get fairly good quality at lower file sizes, would reduce the need for a texture atlas at all -- unless that is just part of your workflow :). Just try to make sure you have crisp edges to go with on your masks and that should work out!

[mcm85_85]

After many attempts I managed to remove the defect by changing the value of Mask Threshold ,

even if, by rotating the object now seem to appear some empty space along some UV border (probably caused by the low-resolution texture).