FSXA Taxiway lines

Hi everyone!

I'm having a little problem in porting an airport designed for FS2004 to FSX. In this particular airport, taxiway lines are generated using scasm commands rrstart and roadcont, preceded by the correct declaration of loadbitmap.
Now, these lines DO show up, the point is that they have the default high traffic road texture, even though the rrstart command specifies to use the last loaded texture. I even tried with a color instead of a texture (setting the first parameter value to 0 in rrstar, of course), but they keep showing up with the default road texture.
Just to be sure of my process, I tried to render them with the first parameter set to 4 (railroad if I remember correctly), and they do use the default railroad texture. I even tried with 6 (which shouldn't be a valid parameter) and they get rendered with the default concrete texture oO

What am I doing wrong, here? Is this approach supported by FSX?

Thanks in advance! =)

I'm not 100% sure these lines are rendered through scasm code, I just decompiled the relative bgl file into a sca file and it looks correct (indeed, it recompiles without trouble).


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FSDevConf team
Resource contributor

I never tried to use these old commands in FSX, but I wouldn't be surprised if they do not work anymore. This technique is really from the time of FS2000 and FS2002.

You could try to load the file in ModelConverterX, it might produce some polygons with the same shape as the lines.
Thanks for the suggestion, arno.
Indeed I tried to open it up in ModelConverterX, but it fails to import it (I don't remember the actual error, if you need it I can tell you) and there's nothing shown, not event the basic grid.
Well, if I try to open the original bgl file in ModelConverterX I immediately get an error saying "The file <file name> is of a non-supported BGL format".

If instead, I decompile the bgl into a sca file (using a very old version of bgl analyze, it should be version 3.1, for decompiling FS98, 2000 and 2002 bgl files), recompile it with the latest version of scasm and open it in ModelConverterX it take a bit longer to open it, but in the end I get a lot of warning and information entries, and no object opened. Just to be thorough, when I open it, it presents me a dialog asking for a value for variable "tod", by default set to 1 (which I don't modify).
I'll list all entries (a lot are repeated):
- Unknown BGL opcode A8 at position 46
- Trying to continue after last jump, might be data block
<repeat the above many times, I guess 200, see later>
- Unknown BGL opcode A6
<this one above only once>
- Starting reading of subobject <n> (where n is from 0 to 199)
- Unsupported command AntiAlias in line 64
- Finished reading of subobject <n> (where n is from 0 to 199)
<repeat the 3 above 200 times, from 0 to 199, generally with odd values missing the unsupported command warning, but sometimes having 2 consecutive objects with the unsupported command warning, thus swapping the order of skips>

Now, looking at the scasm file, there are indeed 200 objects (plus one flatten polygon which doesn't seem to be taken into account by ModelConverterX). Following the same rule seen in the list of warnings in ModelConverterX, I have "objects" composed of road commands (these generate the unsupported command warnings) and "objects" composed of dot commands. I don't know if this is useful.

Maybe related to the problem, if I reopen with ModelConverterX a ground polygon bgl converted for FSX using ModelConverterX ground poly wizard, the program is able to open it, but I still get a Uknown BGL opcode A6 warning once. Any clue what this may be?

Once again, thanks for support! :)


Staff member
FSDevConf team
Resource contributor

Let me take a look. It could be that those road commands are not supported yet, you are probably seeing their opcodes in the log.
I think your right. I don't have the exact errors here, but I remember trying opening the scasm file in ModelConverterX and it was unable to interpret road commands...