Hi Art:
To help others help you better, a few questions are in order, IMHO.
When you refer to "
photoscenery", do you mean custom photo-real aerial imagery compiled via FS SDK Resample (which is technically a special form of "land class") that uses textures and placement mapped from within the same BGL, and that requires custom annotation by *an.agn files with special file names mapped to LOD-13 sized aerial imagery tiles within such BGLs ?
And when you refer to "
a blendmask.bmp exported from GIMP to eliminate areas outside the airport boundary", do you mean a 8-bit gray scale TIF which adds a transparency attribute to the custom photo-real aerial imagery referred to above, so that the aerial imagery is no longer seen outside the airport boundary, and the underlying (standard type) land class textures from either FS default or other 3rd party add-ons is allowed to show through to the top ...
instead of the custom photo-real aerial imagery ?
IIRC, where the 8-bit gray scale TIF '
blend mask' imposes a transparency attribute greater than 128 out of the total 256 possible gradient values, one would begin seeing autogen annotation by *an.agn files with file names mapped to the underlying (standard type) land class textures from
either FS default or other 3rd party add-ons; that autogen mapped to 'standard-type' land class is gradually displayed
instead of
custom autogen annotation by *an.agn files with special file names mapped to custom photo-real aerial imagery BGLs.
This means that for the '
blend mask' to function as a "
Alpha channel", the "transparency" attribute would be implemented by use of (more 'opaque') Hex values of
less than than 128 out of the total 256 possible gray scale values within the 8-bit gray scale TIF '
blend mask' ...for scenery areas
outside the airport boundary.
So, IIUC, when you state "
At one airport the landclass in the blendmasked areas appear with autogen, but at another airport, the autogen is missing in the blendmasked areas" ...I am compelled to ask:
* Did you use a 8-bit gray scale TIF '
blend mask' with
identical transparency attribute values at each of the airports in question ?
Alternatively, I would be curious as to whether there might otherwise normally have been
any autogen annotations mapped to the underlying (standard type) land class textures from either FS default or other 3rd party add-ons that are displayed at the airport in question instead of
custom autogen annotations, as a few (standard type) land class texture types do
not have any autogen annotations.
So, when your airport in question is displayed in FSX with
NO custom photo-real aerial imagery compiled via FS SDK Resample and its associated custom autogen being loaded from (1) or more BGLs in an active scenery sub-folder:
* Do you see
any autogen on the underlying (standard type) land class textures in areas outside the airport boundary ...at the airport in question ?
BTW: Additionally, I am compelled to ask whether you also used both the "Exclude Autogen" and "MaskClassMap" attributes for the GUID of any airport background / boundary
flatten polygons you may have created and are loading from (1) or more BGLs in an active scenery sub-folder ...for each of the airports in question ?
Hopefully your answers to these questions may help sort out the basis for this curious scenario.
GaryGB