Alpha/Transparancy problem with meshes

[Ywa*NL]

Hi everyone,

I've got a problem with alpha/transparancy. I've already asked for a solution on IRC. But they couldn't help me .

I think it's the best if I just paste the link to the IRC conversation so you guys know the exact problem and the things I've already tried to solve it.

Here's the link: http://pastebin.com/ffba1e00

Any help is welcome.

Thanks in advance.

Regards,
Ywa

[rootsage]

I believe you'll need to add an alpha channel to your textures, using something like Photoshop, and then use:

Code:

Scene.SetAutoTransColor(CONST_TV_COLORKEY.TV_COLORKEY_USE_ALPHA_CHANNEL);

This is, at least, how I do it.

[Ywa*NL]

That doesn't help. And how do I add an alpha channel to my textures? Save it as DDS?

[ZaPPZion]

you need photoshop or gimp or something like that for it. You can add an alpha layer in there, then save it as either *.tga, *.png or *.dds
I know that these 3 will support alpha channel stuff.

[phether]

If I read correclty you are using JPGs.
JPGS do not support an ALPHA channel.
As such you have to specify a specific color for the engine to treat as transparent (not the recommended way of doing it, a better way is to use a textur format that supports an ALPHA channel)

The TrueVision3D engine lets you specify what color (as indicate by other posters) to use for your 'auto-transparent' color.
Again, I highly recommend learning to use a decent 'paint' program (i.e. Photoshop) and use a format that supports ALPHA channels and create the transparency you want right in the texture.
PNG are my preference because I also like to use the same textures in a non-3d environment and it doesn't deal with DDS or TGA well.


There are a few more options to using Photoshop, but could take a bit more work.

For example:
Microsoft DirectX Texture Tool will let you create a DDS file from another texture file. You can also load a (greyscale) Mask file to merge with your DDS file to create it's alpha channel.  You will have to read the documentation on how to do this though, it has been to long since I have last used teh DX Texture Tool.

cheers,
paul

[Zaknafein]

Woah, long time no read, phether. Nice to see you're still around.
I've nothing to add the the above posts, just wanted to say hi. 

[jviper]

I have one more peice of information that I have been given about this problem that may or may not have been mentioned here: He has a problem exporting models to TVM format from 3DS MAX when he is using Windows Vista. The exporter to TVM from MilkShape how ever works but apparently does not support .dds textures (you can either confirm or deny this as I have never used MilkShape for my modelling).

I will ask this however: Does 3DS MAX support .dds texture format? If so will the dds format still be supported through the 3DS MAX Exporter to TVM? If so, then my ovious suggestion would be to use .dds when you are modelling in 3DS MAX so that when you export, dds will be used.

[DarekRuman]

Hi everyone,

I've got a problem with alpha/transparancy. I've already asked for a solution on IRC. But they couldn't help me .

Hey, did you set SetBlendingMode(TV_BLEND_ALPHA,-1); to your mesh? Without it - even if you have transparent texture - mesh will not use alpha. Works for me - and i'm using dds format

[pabloescobar]

I will ask this however: Does 3DS MAX support .dds texture format? If so will the dds format still be supported through the 3DS MAX Exporter to TVM? If so, then my ovious suggestion would be to use .dds when you are modelling in 3DS MAX so that when you export, dds will be used.

Yes, 3ds max have full support to dds format.

[Ywa*NL]

I'll try all those things you mentioned guys. Thanks.

Btw... It's better to use the 3DS -> TVM converter from TV3D then using Milkshape 3D .

Although I still got the question. Why doesn't it work to just simply add a texture as diffuse in 3dsmax and the alpha texture as "Alpha" (Like this)?

[pabloescobar]

You really should read this http://wiki.truevision3d.com/tutorialsarticlesandexamples/using_dds about DDS format. If you really want use other texture format (like TGA, that u r using in SS), then the way to add alpha is this:

Code:

tex = TextureFactory->LoadTexture("c:\\thepath\\vn1.jpg");
texaplha = TextureFactory->LoadAlphaTexture("c:\\thepath\\vn1a.tga");
texwithalpha = TextureFactory->AddAlphaChannel(tex, texalpha, "mynew_texture_with_alpha");

And your last chance to use DDS format... 

Code:

TextureFactory->SaveTexture(texwithalpha, "c:\\thepath\vn1.dds", TV_IMAGE_DXT5);

[Ywa*NL]

I've got a DDS now with the alpha channel.

But how do I load the DDS good in 3ds? When I load it as diffuse color it doesn't got alpha. And when I add the same DDS as alpha and diffuse there's alpha. But not good (it uses to normal texture as alpha I think). How to solve this?

Thanks in advance!

[pabloescobar]

Just set the same DDS texture in diffuse and opacity channels in 3ds max material editor, just like the picture bellow.


http://img258.imageshack.us/img258/5962/screenshot122pn5.jpg

[Ywa*NL]

It works now .

Thanks guys and especially pabloescobar .

[pabloescobar]

ur welcome... 

ps: actually you dont need set the opacity channel to export as TVM/TVA, the diffuse is enought. The opacity channel is only to watch the alpha effect in 3DS Max.