Alpha Channel?
- Thread starter DaleRFU
- Start date
You'll have to be more specific. Alpha Channels are used in any number of areas. . .aircraft, scenery objects, autogen and so on. In general terms, yes you can, but what exactly are you referring to?
jankees
SOH-CM-2025
in general: no. The alpha serves to define the shine on all the aircraft I've come across so far. There could be exceptions of course.. Most FS2004 aircraft were the same I believe, though there I have come across a few where a dark alpha meant transparant colors. That's what you're after I guess?
fsafranek
SOH-CM-2024
In FS2004, depending on the material properties of an object on an aircraft, you could use an alpha channel in the texture to either increase the reflectivity of an object (from a light sheen to the extreme -- chrome) or you could use it to effect the opacity of an object (from adding a colored tint to glass or adding window holes in a fuselage side or completely removing external fuel tanks). Both worked great and both had their place in aircraft development.
But with FSX it works differently when it comes to effecting the opacity. You can still effect canopy color but at the cost of clouds looking strange behind the glass. You can still completely remove things like external tanks and other items but the result is that you can then see through where they were. If you park an aircraft in a hanger with fuel tanks removed via an alpha channel the tanks will be gone but you will see the outside scenery through fuel tank shaped holes in the hanger sides.
So using an alpha channel is rarely used to remove things in FSX and "spec" textures (with alpha channels still) are used to effect reflectivity.
But with FSX it works differently when it comes to effecting the opacity. You can still effect canopy color but at the cost of clouds looking strange behind the glass. You can still completely remove things like external tanks and other items but the result is that you can then see through where they were. If you park an aircraft in a hanger with fuel tanks removed via an alpha channel the tanks will be gone but you will see the outside scenery through fuel tank shaped holes in the hanger sides.
So using an alpha channel is rarely used to remove things in FSX and "spec" textures (with alpha channels still) are used to effect reflectivity.
Mach3DS
Charter Member
FSX (And P3D) can do this per pixel which is very nice. From reading on the FS developer forums the SDK describes the diffuse map alpha channel as affecting and objets reflectivity, and the specular map alpha channel as focusing in on the illuminated area "the shiney part" and providing an alternate viewable "illuminated" texture. The specular file controls the "Shine" or amount of light reflected whIle the diffuse alpha control how much reflection of the environment is displayed. Using varying and complimentary amounts of alpha in both files will give you access to extraordinary results for material texture not just material color. At least from my experience. 
The posters above I consider pros in this field, and you can see it in their work. You would do well in finding their work asking questions and seeing how they accomplish things. They really have mastered it's use!
The posters above I consider pros in this field, and you can see it in their work. You would do well in finding their work asking questions and seeing how they accomplish things. They really have mastered it's use!