Model Opacity

FOO FIGHTER

FOO FIGHTER

Charter Member
I remember reading here about adjusting model opacity through a hex editor, but can't seem to locate that thread. Would very much like some information on how to accomplish this. Specifically, making an invisible model visible and hiding portions of another (like guns).:ernaehrung004:
 
Far out! I've got a stock P-47d with a reflective texture now!

Thanks very much for the link.:jump:

Overall model opacity is still a bit confusing but I'll keep trying. The guns I'm trying to get rid of are not tied to any texture sheet. Is there a way to make them invisible?
 
Not that I'm aware of.

If they are mapped from a texture sheet, then you could add an alpha layer and make just their area transparent (black for transparent with everything else white so it will remain opaque). I used this approach to extend the Cockpit window area of the C-47 Dakota to turn it into the Showa L2D3 Tabby.
 
It is possible using the hex editor. I believe it is explained in the tutorial, you just have to find the section that deals with that part in the materials section of the m3d. This is actually how glass parts are done in most models. Glass is usually not textured, and is made transparent in the m3d file.

Color and opacity of non textured parts is controlled in by a four byte section that might look like this in your hex editor: 00 FF 00 FF. This describes a pure green part with no transparency. The first three pairs define the color, blue first, then green, then red, and the final pair controls the opacity. 00 is invisible, 35 is a typical glass transparency and ff is of course fully opaque.

So if you can locate the section for your non textured guns you should be able to make them disappear. The only catch may be that more parts than just the guns could be defined in that one section and thus would disappear also.

I hope that helps!
 
@MajorMagee - Ahh, that's right. So in theory, I could make the turret on the stock B-25C disappear?

@Gecko - OK, I think I got it. The hard part is isolating the numbers for the guns (they are black and not on a B-25). These would not necessarily be in the first nine pairs then?
 
Man, this is really mind blowing and opens up a whole new dimension in mod'ing.:pop4: I really wish I had paid more attention to this information years ago. I can't thank you guys enough for pointing me in the right direction.:ernaehrung004:

I have successfully given several aircraft reflective textures where they had none before. I have almost entirely removed the guns from the stock B-25C with the alpha trick. This seems almost like magic. If you look at something like the B-25J and all the variations of it that existed, you could make a fair amount of those just by alpha-ing this or that on the stock CFS3 model.

I know what I will be doing for the foreseeable future.

I did hit one road block with the B-25C turret. This black frame still remains. I have alpha'd the main texture and specular (now reflective) texture and have alpha'd the entire b_25c_c3.dds, all in a standalone aircraft. I have removed the turret station from the XDP and the turret cockpit model. Any ideas why this is still appearing (I realize the glass is a separate opacity issue)? I have completely removed the nose guns without a hitch. The exception being a few texture 'scraps' that I failed to alpha on the first attempt.
 
Your pics suggest the turret frame is modelled with plain black (unmapped) in the gmax original, no texture has been applied. It won't change whatever is done if that's the case.

The turret model is only displayed when in turret gunner's VC position. The frame you see is part of the main B25 model.
 
Yes, it will take some trial and error, but you should be able to find them. The glass and the frame can both be made invisible in the hex editor, but as they don't appear to have a texture associated with them, using the alpha channel of the textures will not work.

If you have been able to determine where the information for each material starts and ends (see figure 10 in the tutorial) then you should be able to find the opacity value. It will be the last pair in the third set for that material (see figure 15). Since the material is untextured and most models usually have several untextured parts, you will have to test the change on each untextured material until you get the frame and the glass to disappear. Hopefully other parts that you want to keep aren't also part of that material as they would disappear too.
 
The B25C only has one entry without a texture assigned, and that's for the glass. The framing was created with two layers in the model. An outer one textured from _c3.dds and an underlying one from a dark area with rivets on the _t.dds. There appears to be an area of framing for this on the main texture.

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@MajorMagee - Are you referring to the area right above the starboard nose on the main texture sheet?

My initial enthusiasm has been tempered by recent failures on the B-25J. I don't know what was going on but it took five attempts to give it a reflective texture and for some reason the nose section is not reflective. The nose and fuselage guns also have the same turret issue as before. I also noticed later on that the materials follow a nose to tail pattern. I'll keep hacking away at these until I get it figured out.


I have discovered that the turret cockpit model has to remain in the model folder and appropriately alpha'd. It's respective station within the XDP is removed. I also had to copy the Mackenzie texture, rename it, alpha it and make the appropriate name change in the M3D.


After fool'in with those damn B-25's for the better part of four hours and gaining a very, very small degree of experience, I managed to do this to the Dragonfly in fifteen minutes. You may ask 'so what?'. For me, after so long, I was so happy I wanted to cry.
 
CFS3 can be a cruel mistress at times. From things like forgetting to delete the bdp file, to overlooking a dds file reference that needed to be changed in the mos file, to multiple copies of a texture name lurking in other directories I've spent days tracking down things that don't behave the way I expected.
 
The nose to tail pattern is interesting. I wonder if gmax organizes it that way or if has to do with how the modeler made it.

Anyways, did you notice there are two materials that reference the main texture? One is for the nose, one is for the rest. Keep plugging away, it will get easier.
 
Well, this experience has been bitter sweet. I did not achieve my ultimate goal but I gained a great deal of knowledge through the experience. I solved the nose issue but it now appears that the fuselage and turret use the same material, . . . bummer. My TB-25J will have to be a B-25C with a turret, which isn't impossible I guess for a MATS bird in the KTO.

I thank you gents again for the assist. I will definitely put this info to good use on other projects.:ernaehrung004:
 
Well at least you learned some useful stuff. It opens up a lot of possibilities, though as you've found, not everything is possible.
 
I just wanted to say thanks again. This info has been invaluable in my endeavors since.

I also wanted to add that I have discovered that the t.mos voids any alpha changes to a texture. Any alpha'd parts will show black. The only way (so far that I know) around this is to delete the t.mos.
 
That's correct, for a .mos to work you cannot have alpha on the texture referenced by the .mos file.
 
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