Transparent Walls?

I'm using Doom Builder 2, and I wish to know how to make transparent "walls," like in the last room of Doom I with the brownish-metal cracks.

Put a respective transparent texture onto a double-sided linedef as a middle texture, and flag the linedef as "impassable".

RetroNova10 said:

like in the last room of Doom I with the brownish-metal cracks.

Which map and where?

I used GZDoom Builder and UDMF, but it might also be appliable in DB2.
In this screen shot, we can clearly see the alpha setting.
By default it is 1 as seen in the shot.

Alpha means how much a wall is transparent.
It's like a gradient, from 0.0 to 1.0, where 1.0 = opaque and 0.0 = invisible, so that 0.5 is 50% translucent.

scifista42 said:

Put a respective transparent texture onto a double-sided linedef as a middle texture, and flag the linedef as "impassable".
Which map and where?

Oh, I'm sorry... completely forgot to specify. The first level, in the last room. The room before the room with the exit switch.

Thanks a ton, scifista42. Worked like magic! I never knew you could texture a linedef.