Embed alpha channels in tiffs for car decals

[soulburn3d]

Well, how are you trying to save the tiff?

In photoshop, place in an extra channel your alpha information, then save as tiff, and it should just save the correct information.

Or, you can place your color information on a layer, remove the "background" layer. Then when you save your tif, make sure to check "save transparency", which will also create the proper alpha channel for you.

- Neil

[Noomski]

Hi Neil,

Thanks for the tips, with regards to what you said here:

Or, you can place your color information on a layer, remove the "background" layer. Then when you save your tif, make sure to check "save transparency", which will also create the proper alpha channel for you.

I think I'm doing this right, see below:
http://img170.imageshack.us/img170/7052/tiffsave1nd3.jpg (http://imageshack.us)

Closeup
http://img519.imageshack.us/img519/9310/tiffsave2hv5.jpg (http://imageshack.us)

http://img519.imageshack.us/img519/6227/tiffsave3rm4.jpg (http://imageshack.us)

Looks like I'm doing what I'm supposed to but it just will not work for me no matter how many times I try.


The other option you mentioned was to add an extra layer in the channels pane (below 'RGB', 'Red', 'Green' and 'Blue' layers). I tried this and my image either came out completely white or completely black.

[Noomski]

Ok,

I think I've taken 1 step forward and 2 steps back.

I'm pretty sure I've got the tiff saved correctly now but there is another problem I'm getting when trying to apply it.

Previously I used the 'Esso' logo given in the tutorial and it worked a treat :) However I've gone back to try it again and it's giving me the same problem I keep getting with my 'Concept Five' logo everytime (see below)

The esso logo didn't do this before and for some reason when I render this out I have no paint texture to be seen, It's just white. I think i'm going crazy I've meade it work myself once but I just can't get it to work again... ARRRGGGHHHHHH!!!

http://img84.imageshack.us/img84/6162/essoproblemul9.jpg (http://imageshack.us)

[Cameo]

Hi Mike

Its a little hard to tell whats meant to be happening in your last post without being able to see the uv's/texture for the object. I cant check out your original link as it seems to be members only. Can you elaborate any further?

[Noomski]

Hi Cameo,

Basically in the image below i've shown how the wheel should look with the smoothing and paint textures applied.

http://img523.imageshack.us/img523/5259/paint01gx8.jpg (http://imageshack.us)
In this image I've applied the logo (this time I tried my 'Concept Five' logo instead of the esso one in the above post). As you may be able to see the logo appears perfectly on the spoke polys that I selected, however when I render it out the paint is no longer visible.

I can't help but think that, as seen above in the 'esso' example, when I bring the tiff over to the object it covers the entire surface with a really distorted image of my decal. But it shows really clearly in the area where I want it. I think this is the problem.


http://img520.imageshack.us/img520/2152/paint02rh8.jpg (http://imageshack.us)

(http://g.imageshack.us/g.php?h=520&i=paint02rh8.jpg)

[Cameo]

Could it be something to do with material ID's in max? In your esso image it looks like the same logo applied multiple times on different faces at difference sizes etc?

Im not a max user but there should be an equivalent to what in maya is known as a layered shader, this could be another route you could take. It would allow you to have the paint shader at the bottom of the layer stack and then ontop of this you could layer any additional decals/details (using alphas) without disturbing the paint shader at all.

[Noomski]

Hi Cameo,

Thanks for the info, I think you are right about material ID's etc, this is what the guy who wrote the tutorial said at the end:

Ok, some usefull tips. Always make sure the Map channel ID is the same on map and UVW map modifier. Always use TIF files. Remember to turn of tiling.

Also you can run into problems if you have ' show map on backside' turned on. Most of the time I split my materials up, for example a Multisub map, one with a basic paint shader for 99% of the car. The other is the same paint shader with the composite map on. Then I poly select ontop of the meshsmooth, change the Material ID and use the decal material. This makes sure there are no rogue maps popping up. Its a matter of preference and work flow, Im sure you will find a way.

Now I've only been using max for a couple of months and I'll be the first to admit that I'm not really 100% sure what is meant by some of tips he's given in the quote above. but I'm sure I need to be doing something to keep these materials seperate or something.

If it helps I've taken screenshots of the material editor at each stage of the tutorial:

http://img142.imageshack.us/img142/4215/51911763wi7.png (http://imageshack.us)http://img75.imageshack.us/img75/2589/87710545xr0.jpg (http://imageshack.us)

Then I assign the new material to the object and reposition it on the correct spoke of the wheel, hit render and the decal is perfectly displayed on the spoke and my paint is completely hidden :( .......

[Cameo]

I played with max many years ago but i seem to remember in the options rollout for the uvw modifier that there was a bank of 20 or 30 number boxes which corresponded to material ID's. Sounds as though these have to tally with what you have in your material editor? I would seek the help of someone proficient in max though, your problem seems quite specific.

[Noomski]

Hi Cameo,

You are absoluteley right - the guy said this in the tut' and i've made sure mine match up correctly too. Must be something else wrong with it..

Thanks for the pointers tho

[scrimski]

I can't help but think that, as seen above in the 'esso' example, when I bring the tiff over to the object it covers the entire surface with a really distorted image of my decal.

That's because you applied the UVW-mapping only to selected polys.
Anything else has no proper mapping coordinates, which results in stretching and other distortions.

And you don't have transparency in your decal because you have no alpha channel in your picture, just R,G and B. Saving transparency without defining it first doesn't make much sense.

Create another channel(should be blak by default, if not, change it to black), go back into your logo layer, CRTL+leftclick it, go back into the alph channel and fill the selection with white.

btw: Whats the point of having three TS modifiers? Use one and alterate the iterations.

[soulburn3d]

Looks like I'm doing what I'm supposed to but it just will not work for me no matter how many times I try.

You're almost there. Just change the radio button at the bottom of your tiff save dialog from RLE to discard layers. You don't want to save the layers, you just want to save the transparency.

- Neil

[Noomski]

Hi scrimski,

Many thanks for the pointers,

I've done away with applying the uvw to only the selected polys as I realise now that there was no need for this.

I've also added the black alpha channel correctly earlier today (in photoshop's channel pane I now have R G B and Alpha, which shows up black with the logo selection visible in white in the thumbnail in the channels pane - I guess thats right).

However, as far as the transparency goes, I've tried to use the logo's supplied in the tutorial I was following and they are also acting the same way as my logo. It did work for me once with the supplied Esso logo but I can't for the life of me understand what I've done differently cos I just can't repeat it...

As for the TS modifiers I really am quite new to 3ds max and it seemed to be getting effect I was looking for, so I'll look into this too.

Many thanks for your help, I'd be really interested to hear if you may have any other thoughts as to why this is happening.

[Noomski]

Hi Neil,

i tried what you said and still no joy, It just covers up the paint the same as all the other tiffs supplied by the tutorial author.

The way I'm working with this right now is to try and get the esso tiff from the guys tutorial to work first as I know there is no problem with the way this one is saved. Plus I know it works cos I got it to work - once :shrug: .

Just a process of elimination really. Once thats sussed I'll try my tiff in it's place.

[BOY1DA]

Well once you have the transparency figured out for your maps....

To combine many images in layers you want to use the composite map
with multiple UV channels.

Below are some video tutorials that I made a long time ago.
I show how to use composite maps and multiple UV to place decals.

http://fetch.boy1da.com/video_tutor...siteMapDEMO.rar (http://fetch.boy1da.com/video_tutorials/CompositeMapDEMO.rar)

[Noomski]

Thanks BOY1DA,

Thats awesome help, many thanks :bounce:

[BOY1DA]

You're welcome, happy to help :)

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