Hello everybody,
As most of you probably know, we released a new version of our Helsinki-Vantaa (EFHK) scenery a couple of weeks ago. The scenery features a gmax-based ground scenery which works just fine on most computers. However, after the release, I recieved reports that some users are experiencing some really weird problems with the ground scenery. They reported that the ground works as it should when they are departing the airport but on approach it has completely disappeared. Interestingly, this peculiar problem occurs only on some computers, excluding mine, which makes it really hard for me to try to solve this issue.
Two of those who are experiencing this problem have been willing to test some modified ground bgls for me and so far we've concluded that everything works fine as long as you start your flight at EFHK and stay within about 10nm distance from the airport. However, when they slewed to the distance of about 25nm from the airport and then slewed back, the ground scenery had disappeared leaving only the VTP polygon underneath visible. As I'm starting to run out of ideas on how to solve this issue, I decided to give you a detailed description of the problem and hope that you could be able help me out.
First of all, the basic structure of our ground scenery is that underneath everything else there is a Ground2k-made VTP grass polygon which is there only to confine the autogen trees to areas outside the airport itself. The culprit, that is, the gmax-based ground scenery, lies right on top of it. It initially consisted of various ADDCAT layers, but as I tried to troubleshoot this problem I consolidated the whole ground scenery into one layer. Here is the source code of the wrapper file for the ground scenery:
The sources for the ground polygons can be downloaded here.
As I scrutinized this issue, I noticed that it doesn't matter whether you construct the ground using various ADDCAT layers or using the technique above. Regardless of the method used, the same problem still persists. The TRANSFORM commands were an experimentation to raise the ground a little and see if it helps but, unfortunately, it didn't. I also tried to convert each of the ground polygons into library objects and place them using SCASM and its LayerCall but it worked neither. Once again, the ground was gone when the test pilots flew far enough from Helsinki and then returned back there.
Strangely, one of the testers reported that the ground scenery of our Helsinki-Malmi (EFHF) works just fine. The ground of EFHF is created using the same methods I used at EFHK but apparently there is a vital difference somewhere. I wasn't able to locate the crucial distinction myself but maybe you are. The source code of EFHF ground scenery is available here.
This finding led me into thinking that there might be a problem with the flatten file our our EFHK scenery. I've, however, double checked that both the flatten and the invisible runways used to create the PAPI lights are placed at the same altitude of 54.57 meters - and as far as I know, those are the only files which include information on the altitude of the airport. Here's the SCASM source of the flatten file:
The testers reported that when I experimented with zbiased ground polygons without the ADDCAT command this problem didn't appear. That approach, however, leads into an abundance of other difficult issues such as layering, flickering, bleed-through and tranparency problems which are gone when using the ADDCAT command.
Now, after this lengthy account of this problem, I look forward to hearing if anyone of you has run into this kind of problem before and, better still, would have an idea on how to solve this. As far as I know, only a minority of users are experiencing this problem, but I would like to give them as well a possibility to enjoy our newly-released scenery.
As most of you probably know, we released a new version of our Helsinki-Vantaa (EFHK) scenery a couple of weeks ago. The scenery features a gmax-based ground scenery which works just fine on most computers. However, after the release, I recieved reports that some users are experiencing some really weird problems with the ground scenery. They reported that the ground works as it should when they are departing the airport but on approach it has completely disappeared. Interestingly, this peculiar problem occurs only on some computers, excluding mine, which makes it really hard for me to try to solve this issue.
Two of those who are experiencing this problem have been willing to test some modified ground bgls for me and so far we've concluded that everything works fine as long as you start your flight at EFHK and stay within about 10nm distance from the airport. However, when they slewed to the distance of about 25nm from the airport and then slewed back, the ground scenery had disappeared leaving only the VTP polygon underneath visible. As I'm starting to run out of ideas on how to solve this issue, I decided to give you a detailed description of the problem and hope that you could be able help me out.
First of all, the basic structure of our ground scenery is that underneath everything else there is a Ground2k-made VTP grass polygon which is there only to confine the autogen trees to areas outside the airport itself. The culprit, that is, the gmax-based ground scenery, lies right on top of it. It initially consisted of various ADDCAT layers, but as I tried to troubleshoot this problem I consolidated the whole ground scenery into one layer. Here is the source code of the wrapper file for the ground scenery:
Code:
;compile with BGLC /BGL D:\EFHK-scenery\uusi_pohja\pohja.asm
header label word
dw 0001 ; 00 World set number
dd 000665DA4H ; 02 North bound
dd 0006639DEH ; 06 South bound
dd 011C174CEH ; 10 East bound
dd 011C174CCH ; 14 West bound
dw 20 dup(0)
dd (offset OBJECT_DATA) - (offset header)
dw 33 dup(0)
OBJECT_DATA label word
db 21 ;;LATBAND_REL
dw 0331Ch ;;lat min (inclusive) 512M units
dw 0332Fh ;;lat max (exclusive)
dd (offset OBJECT_0) - (offset OBJECT_DATA)
db 0 ;;EOL
OBJECT_0 label BGLCODE
db 12 ; NEAR_FAR_HUGE_OBJECT_HEADER
dd 000664BC1h,011C174CDh ; latitude,longitude
db 100 ; image power
dd (offset OBJECT_0_END) - (offset OBJECT_0)
OBJECT_0_START label word
ADDCAT OBJECT_0_SCALE, 8
INSTANCE_CALL R, 0, 0, 0
BGL_JUMP_32 OBJECT_0_END
R label word
BGL_RETURN
OBJECT_0_SCALE label BGLCODE
SCALE_AGL OBJECT_0_RETURN, 50000, 4579, 131072, 000664BC1h, 06E15h, 011C174CDh, 0998Dh, 0, 0
BGL_CALL OBJECT_0_BEGIN
OBJECT_0_RETURN label word
BGL_RETURN
OBJECT_0_BEGIN label word
model_outside label BGLCODE
model_shadow label BGLCODE
LOD_0 label BGLCODE
BGL_JUMP_32 LOD_0L
model_inside label BGLCODE
BGL_RETURN
LOD_0L label BGLCODE
BGL_BEGIN 0800h ; version = 8.00
;BGL_TRANSFORM_MAT 0.000000,0.100000,0.000000, 1.000000,0.000000,0.000000, 0.000000,1.000000,0.000000, 0.000000,0.000000,1.000000
include D:\EFHK-scenery\uusi_pohja\pohja_0.asm
include D:\EFHK-scenery\uusi_pohja\pohja_paikat_y_0.asm
include D:\EFHK-scenery\uusi_pohja\pohja_paikat_x_0.asm
include D:\EFHK-scenery\uusi_pohja\pohja_rwy_3_0.asm
include D:\EFHK-scenery\uusi_pohja\pohja_rwy_2_0.asm
include D:\EFHK-scenery\uusi_pohja\pohja_rwy_0.asm
include D:\EFHK-scenery\uusi_pohja\pohja_hi_res_0.asm
include D:\EFHK-scenery\uusi_pohja\pohja_hi_res_2_0.asm
include D:\EFHK-scenery\uusi_pohja\rwy1533_0.asm
include D:\EFHK-scenery\uusi_pohja\rwy22R04L_0.asm
include D:\EFHK-scenery\uusi_pohja\rwy22L04R_0.asm
include D:\EFHK-scenery\uusi_pohja\service_road_0.asm
include D:\EFHK-scenery\uusi_pohja\twy_line_0.asm
include D:\EFHK-scenery\uusi_pohja\ground_markings_0.asm
;BGL_TRANSFORM_END
BGL_END
BGL_RETURN
OBJECT_0_END label word
EOF
The sources for the ground polygons can be downloaded here.
As I scrutinized this issue, I noticed that it doesn't matter whether you construct the ground using various ADDCAT layers or using the technique above. Regardless of the method used, the same problem still persists. The TRANSFORM commands were an experimentation to raise the ground a little and see if it helps but, unfortunately, it didn't. I also tried to convert each of the ground polygons into library objects and place them using SCASM and its LayerCall but it worked neither. Once again, the ground was gone when the test pilots flew far enough from Helsinki and then returned back there.
Strangely, one of the testers reported that the ground scenery of our Helsinki-Malmi (EFHF) works just fine. The ground of EFHF is created using the same methods I used at EFHK but apparently there is a vital difference somewhere. I wasn't able to locate the crucial distinction myself but maybe you are. The source code of EFHF ground scenery is available here.
This finding led me into thinking that there might be a problem with the flatten file our our EFHK scenery. I've, however, double checked that both the flatten and the invisible runways used to create the PAPI lights are placed at the same altitude of 54.57 meters - and as far as I know, those are the only files which include information on the altitude of the airport. Here's the SCASM source of the flatten file:
Code:
Header( 1 N89 S89 W179 E179 )
LatRange( N89 S89 )
Area16N
Elevation( 54.57
N60:21:09.0146 E024:57:19.9214
N60:20:04.6652 E024:56:09.6300
N60:19:21.9978 E024:54:37.1542
N60:18:41.7278 E024:53:16.9679
N60:18:30.3240 E024:53:01.2822
N60:17:48.9524 E024:52:16.7500
N60:17:27.6997 E024:55:09.4276
N60:17:20.9611 E024:59:22.9017
N60:17:50.2484 E025:00:34.0702
N60:20:09.1684 E025:00:37.8261
N60:20:40.5291 E025:00:33.3966
N60:21:10.3833 E024:57:40.3441
)
End16
The testers reported that when I experimented with zbiased ground polygons without the ADDCAT command this problem didn't appear. That approach, however, leads into an abundance of other difficult issues such as layering, flickering, bleed-through and tranparency problems which are gone when using the ADDCAT command.
Now, after this lengthy account of this problem, I look forward to hearing if anyone of you has run into this kind of problem before and, better still, would have an idea on how to solve this. As far as I know, only a minority of users are experiencing this problem, but I would like to give them as well a possibility to enjoy our newly-released scenery.
Last edited: