3DC Alpha’s re-visited

I’m planning to write up a more detailed tutorial for TRS in the next week or 2, I’ll post links here and on the Trainz forums once I get it done.

Some time ago, I asked some questions regarding instructions on how to do alpha’s in 3DC.I had a very good response from ‘Bazza’ in the form of a tutorial, which I have read several times.
However, to this day, I have never succeeded to create any alpha textured components.In case I have misinterpreted what I have been told, I have some new questions which I shall accompany with pics. I shall only ask one question at a time to avoid any confusion. My first question is: To create alpha textures in 3DC, which button do I press? See pic 1.
Thanks in advance.
Cheers, Fender <!– s:) –><img src="{SMILIES_PATH}/icon_e_smile.gif" alt=":)" title="Smile" /><!– s:) –>

You don’t need to press any of these to create an Alpha Texture.
You create the texture in your paint app either as a .tga or .png file.
With a .tga file you need to create the alpha channel.
With a .png file the alpha channel needs to be activated.

When you load these into 3DC, the alpha channel is loaded into the Translucancy tab making this area of the image invisible.


Hi Bazza,
I have goofed here – used the wrong word ‘create’. I will re-phrase this question :
Which button do I press to APPLY the alpha textures in 3DC? To clarify further, when I select a certain PART, which I want to be an ALPHA TEXTURE,e.g. a train number plate,then which button do I press in 3DC?
Cheers, Fender <!– s:) –><img src="{SMILIES_PATH}/icon_e_smile.gif" alt=":)" title="Smile" /><!– s:) –>

Further to the above, I should have mentioned I have 3DC pro version 7.1.2. My paint programmes are Jasc Paint Pro 8 and Jasc Paint Pro 9.I have prepared .tga files, but will come to that later – I really want to resolve one question at a time to avoid any confusion.
Cheers, Fender <!– s:) –><img src="{SMILIES_PATH}/icon_e_smile.gif" alt=":)" title="Smile" /><!– s:) –>

1) Create the texture in your paint app with an alpha channel and save as a .tga file
2)Load the texyure into 3DC just as you would with any other texture….Click the Primary Texture tab and load the texture.
The alpha channel will be loaded with it.
3) Select the part you want to apply the texture to and apply with either the Brush or fill tool.
Thats it.


Thanks Bazza, but to really clarify, which NUMBERED button do I press. My pic shows the buttons numbered 1 – to 7. Which NUMBER do I press? Sorry, but I have had one hell of a job trying to perform a task which should be so simple and want to go through the process piece by piece until I achieve success.
Cheers, Fender <!– s:) –><img src="{SMILIES_PATH}/icon_e_smile.gif" alt=":)" title="Smile" /><!– s:) –>

1) Click Button 1 first and set Diffuse and Ambient as you want them. I usually have Diffuse set to 100 and ambient set to 0.
Set Specular and Translucent to 0.
2) Click button two (the Primary Texture button)and load the texture with the Alpha channel.

Thats all you need to do, now apply the texture with the Brush or Fill tool.


Thankyou Bazza. Now here is the crux of the problem – please refer to my attached pic. The lower 3rd of this pic ‘A’ is the texture as loaded in 3DC and the crop around the words ‘New Zealand Railways’. I apply this to the model. It shows in 3DC with the black background.I think at this stage it should show as words only and no black background, but not sure.(TSM works like this)
The middle 3rd of this pic ‘B’ shows the model in Paul’s shapeviewer. This is the TSM created version of the same model and exported to MSTS. As you can see, the lettering is crisp and clear with no sign of the black background.
The top 3rd of this pic ‘C’ shows the model in Paul’s shapeviewer superimposed over the other.This is the 3DC created version of the same model and exported to Trainz.As you can see, the alpha process has failed. Both TSM and 3DC models use the identical texture files.I have checked both .tga files in tga tools 2 programme and both embedded alpha textures show up O.K.The main difference in the same model is the creation programmes, TSM versus 3DC. I conclude that there is something wrong in 3DC or I am doing something wrong in 3DC to cause this alpha to fail.Any clues to this frustrating problem ?
Cheers, Fender <!– s:( –><img src="{SMILIES_PATH}/icon_e_sad.gif" alt=":(" title="Sad" /><!– s:( –>

I think the problem could be in the way you are saving the Alpha Channel in PSP.
See attached pic I made up quickly, the black is transparent.
I used PSP v10 but I don’t think it’s any different to any other version re creating alpha channels.

1)I created the text on a blck background.
2) Selected all the black background with the magic wand tool.
3) Inverted the Selection
4) From the Selections Menu Choose..Save selection as Alpha channel.
5) Save the image as a .tga file

Thats it really, the black background shouldn’t show up in 3DC.
I’m using 3DC v7.1.2.

I can’t help much with getting files into any of the train sims as I don’t use them.
Maybe some of the train sim guys can help with this.

I’m out for most of today so won’t be able to post till later tonight, UK time.



Ian Morgan did a good tutorial ( making a wagon) which covers alpha channel/3DC for MSTS on uktrainsim.com.

If I recall, it also used PSP 7 or thereabouts

There’s also a ‘telephone box’ tutorial by Doug Kightley which I think also covers alpha channel.

I’m certainly no expert, but have got one 3DC model into MSTS with a working alpha transparency – though this was before recent 3DC upgrades so I may have to relearn a bit…. <!– s:) –><img src="{SMILIES_PATH}/icon_e_smile.gif" alt=":)" title="Smile" /><!– s:) –>



Thankyou Bazza and John. I have indeed already followed Ian Morgan’s tutorial. I have done some further tests and I am now convinced beyond any doubt that there is a fault with the Trainz .im exporter in 3DC. I can’t get translucency to export either – anything over 20% fails to export – but it shows O.K. in 3DC.
I set up a simple block like your sample, Bazza, and this shows as transparent in 3DC, but once exported via the Trainz .im, it has returned to solid black background. Paul ? or Richard? any help please.

There is a new thread at the UK TrainSim forum that discusses applying transparency and translucency in the later versions of 3DC. I recommend it highly as it partially makes up for the almost total lack of information given us by Amabillis. [img:1zghwlfx]http&#58;//forums&#46;uktrainsim&#46;com/viewtopic&#46;php?f=18andt=85548[/img:1zghwlfx]
<!– m –><a class="postlink" href="http://forums.uktrainsim.com/viewtopic.php?f=18andt=85548">http://forums.uktrainsim.com/viewtopic. … andt=85548</a><!– m –>


For Trainz:

TGA files that use true transparency (0 or 255 values only in the alpha channel) should set the translucent value to 0
Other TGA files with tranlucency should set the translucent value for the material to between 1 and 5 to set the drawing order.

You only need to use a simple TGA file in 3DC, this should then export to the model folder along with the xxx.texture.txt file.
This file should contain a line starting with alpha= to point to the location of the alpha channel for the texture. I suspect this is where your problem lies.

Transparency does indeed work fine with 3DC and Trainz, for me anyhow.

Here’s an example that might help ..

Say your texture is called new_zealand_railways.tga and has an alpha channel included. Trainz does not show the alpha unless directed to do so in the .texture.txt file that each texture requires.

Your file should be called (for this example)new_zealand_railways.texture.txt The contents of the file should look like this ..


You can copy and paste this and save it if required.

Hope this helps, Tony

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