Bad lights - got any?.

[Guest fu3]

Hi Folks :-waveWould any Seattle region users like to help me find rogue night lighting?There is a lot of it in stupid places - like taxiways and beaches (PAE). It should really represent buildings and streetlights, not open fields, either (Harvey, Asplund etc.) :-rollIf you see some that you don't like or you think shouldn't be there, let me know which airport and roughly where they are (post on this thread). It doesn't matter if you think they're obvious, I'd still like to know ;) I will include all of the modified N2 tiles in a single upload. By then, the fabulous Bruce (all great Australians are called "Bruce") may have worked out how to regenerate the N3-7 tiles ;) ;) and we can have nightlight heaven...Regards,Jon Point

[Guest R_Driscoll]

This is great work Jon! Maybe you could help with adding lights to London? It could use a few. Hans Petter is keen - he's working through our recent bunch of models and fixing up night-lighting. I can do it but I get too lazy, and adding beacons I find very slow too. Pity because the final effects of nightlit buildings are great. But as to the actual night mapping, I think that would make night lighting really take off. I'lll have to learn how to do this.Anyway, get Seattle sorted first - I think this is still the area most people fly. Bruce.(name changed by official deed poll, 29/1/2007).

[Roger Over 0]

's funny..... I don't know any great Australians named "Bruce"... :-rollAlways makes me think of Monty Python tho... *:-* Final version of LightGen2 is just about wrapped up, should be available in a couple of days. (But that's what I said three months ago I think..)CheersBruce

[Guest fu3]

Ah yes, the 'success of the Bruces' - or should that be 'Brucii'?Rob,The trick to adding night lighting seems to be in getting the OT city/suburban night texture to display, than mask it out with N2 tiles. I haven't tried adding them where they, er, aren't but I assume that they're controlled by classification, much like OT tiles are. We're going to need some hefty brainpower to work it out though, and in fact the masking task is probably the easy bit :-rollBruce,As to the final version of LightGen2, can we get it to invert the TGA maps on import? It exports them right-way-up but it's a pain to invert it (or rather, to forget to invert it) and I get highways running up over mountains :-eek The only way to know by looking at it is to export another original and see if it's inverted.All,Obviously you're all happy to have night lighting all over the place and you haven't wanted to use the new terrain! I can't believe that nobody hasn't seen a light they dislike in the past week or so - apart from UKS. Well, I'll keep plodding along, as I flatten airports. I've done 16 so far and Agtim's doing one or 2 so that's 18 tops. I was kind hoping we'd have them all done by now :-rollRegards,Jon Point

[Hans_Petter 1]

Jon, I'm sure that we'll be able to pinpoint some rogue lights but I haven't had time to look for them yet. However, there's a general problem to spotting rogue night lights -- it's pretty hard to decide which lights are for real. Any area by night will look very different from the same area in broad daylight. Thus, it takes a lot for rogue lights to really stand out as obvious artifacts. That's why generic night lighting works quite well -- as long as the lights come in patterns indicating roads and building blocks they seem fine. Unless they show no respect for shorelines or cross runways that is :-)Hans Petter

[Guest fu3]

H-P,I'm not at all concerned about lights away from airports - except for 'field parties' and 'beach parties' (for some reason, thermal sensing counts beaches and open paddocks as places of human habitation :-lol ).The ones that really annoy me (and probably a few others...) are lights on taxiways and runways, as well as those one sees on approach and takeoff where there should be nothing there.I also got rid of my major pet hates - those huge blocks of lights near Auburn Muni that one can see from Portland (almost). Close-up they're blocks of suburban lighting but from a distance (more than 1-2 miles) they coalesce into huge blocks of yellow light.And what were they?Grassy fields of course :-rollI worked out last night that I'm about 33% done with the Seattle lights but I'm sure everyone will find something they don't like - after I release it ;)Regards,Jon Point

[Guest R_Driscoll]

I just wonder if the original light maps were developed directly from the classification tables? Maybe the LGS white pages mentions this somewhere. If so, then all we would need to do would be to correct the individual tile classifications.

[Guest fu3]

Rob,What? The original "OT"-style suburban lights or the "real" ones? The ones were derived from thermal imaging, which is about as accurate as the current CPI* and obviously about as useful. LGS must have deleted swathes of useless junk, before giving up (somewhere near Auburn Muni) and changing over to the currently filtered setup...*Consumer Price Index: An indicator of the inflation level apparent in our society. Of course, here in Oz at least, they ignore things like and ...The OT thing may be a bum steer, although it appears that's what the underlying texture is. Maybe just by coincidence they used the same pattern. Unfortunately, I cannot get away from the fact that if I modify an N2xxxx tile for 'lights everywhere', the OT suburban pattern is what I get!Bruce (Almighty of Alstonville) offerred that if I wanted lights on a tile that didn't exist (in Seattle, quite a few - 29 - aren't present), I could add them by just creating the relevant file (TGA, 256x1024) and putting it into the nitemaps folder! Sorry Bruce for 'dropping you in' there but... Don't tell me this is as simple as creating N2-N5 maps for UKS and just putting them there :-lol ? Bruce (the same) has also offerred about the upcoming LightGen2:"BTW the new version has a facility to extract the L1 day map for thesame tile when the night map is extracted. Won't work for compressedmaps just yet tho."Aaaaaaand, sorry again Bruce for dropping you in there - again! I assume that CPD files are 'compressed' maps? So binfiles are OK? Nightflying UKS here we come :-jumpyRegards,Jon Point

[Hans_Petter 1]

I'm a bit unsure what you get with thermal imaging but I know this for sure -- heat or IR is what you record. This will coincide with human activity in most cases and light in several cases. I'm just a bit puzzled why beaches and paddocks ("fields" to us non-Aussies) get night light. They must emit heat. I can see that a beach may emit heat when the sun is shining and so would rocks. But why would a grassy field emit infrared light to any significant extent?The rogue lights around airports may be explained by a "live" aircraft that was there when the thermal image was being sampled. The engine would emit a lot of heat and show up as a spot of light when you interpret IR as being light.Hans Petter

[Roger Over 0]

Hi all,Jon, thanks for dropping me in there..... :-roll "Don't tell me this is as simple as creating N2-N5 maps for UKS and just putting them there :-lol ?" Yep. Except that you have to work out where the light is going to be (and not be) more or less. We can't pinpoint a particular spot and light it. Remember each pixel in a n2 night map represents about 256 square metres, if my maths is correct. The underlying grid will display light from any of its "lit" pixels that fall within that area. Creating a new map (I think I prefer to call it a "mask") generally is done by:1. Extract the day map (LG2 (LightGen2) will do this for a .bin file, .cpd (compressed are a little more tricky and will take me a bit more time I fear)2. Using the day map as a reference, select the area you want to light3. Fill the selection with a color or pattern (any color will do)3a. Invert the selection and fill it with black (palette index 0)4. Save the selected layer as 256X1024 tga file5. Build the l2-l4 .bin files with LG2. You can also build l5-l7 if you want.6. Copy to the region/maps/nlights folder7. Use LG2 to "switch" the tile on.You do need to "switch" the night map levels on in the tilindex using the switch function of LG2.... Of course, the day map must already exist for that tile, otherwise it ain't going to let you switch it on.The OT texture is similar, but as far as I can see only displays yellow. The hi res texture is at least multi colored to give a more realistic urban effect.If anyone out there knows where the underlying texture is located I would be pleased to know. As far as I can see it is hard coded, and so unreachable by us lesser mortals. I guess it is possible that it is stored in a res file somewhere.Cheers :-wave Bruce (the lesser)

[Guest fu3]

H-P,Looking at a thermal satellite image of my neighbourhood, the brightest things are the new shopping mall (white concrete) and the beaches themselves (white/yellow sand). The black asphalt 6-lane is about as bright as my roof and the houses are similar. This would give us lights in the suburbs and on roads, but heaps around the concrete commercial and industrial structures, as well as the beaches. Hmmmm, something like FU3 :-roll The fields causing most of the problems are either dark (i.e. ploughed or dirt) or very light (i.e. dead grass/bare ground). The ones near Auburn are a freak (I think LGS ran out of time/patience). I guess it would be better if these things were actually done at night :-lol :-lol :-lolRegards,Jon Point

[Guest R_Driscoll]

Weellll there's a lot here I don't understand, but its just starting to sound possible. I was thinking the classification maps might be a useful starting point since they are accessible and related to concentrations of human activity, but I think I'd better wait and find out more. I get the drift of what you are doing, but the fine details are beyond me. I'll have to wait for the 17 volume how to manual with demos, tutorials, problems and worked examples. Next week?Great work,Robert.

[Roger Over 0]

Hi Rob,Well..... next week if you only want the story board, slide show and multi-language manual. If you want the free steak knives you will have to wait a bit longer :-hah I think it is important to keep the role of night lighting in a realistic perspective. I am sure that LGS only intended that their version of night lighting was meant to be a navigational tool to help VFR pilots "in the dark" to identify large infrastructures (towns, highways etc) from a distance.It was never intended to show where the drive-through entry to the downtown Burger King was. For that we have models, and the wonderful talents of you folks who put those amazing things together.So, night lighting is not the answer to every prayer. It is just another part of the big picture.Anyway, that said, I'll be orf. Gotta do some work.CheersBruce H

[Guest fu3]

Bruce,I agree, but speaking from preference, I prefer flying at dawn and dusk. Sky colours, you know... Of course, put me at a real set of controls and I'd prefer between mid-morning and early afternoon. Ground colours, you know...When flying for real, I couldn't care too much about sky colour, except that if looks 'pretty' or 'interesting', I'm probably about to go IFR :-lol Either way, I don't even have night VFR yet :-rollColouring (or rather, masking) for UKS should be pretty straightforward - just the sheer number of tiles to deal with. I had a look around last night and the vast majority of UKS only needs along major roads, with a few dotted around the countryside, where houses are. The cities are different but I'd like to try selecting colours (other than roads and buildings, for example) and making them transparent, then using the remaining pixels as the basis for city streets etc. This can be automated with a script in Corel, so if we had the L0 TGAs, I could sit back and enjoy the power of modern computing!All I need are the textures to start with. The L3 tiles I use for elevation and existing nightlight placement are too low-res to find things - I often resort to FLED to locate objects (like runways :-lol ).Oh, and I can't seem to open the tiles. I did some playing around Land's End last night (by placing some renamed Seattle tiles into the UKS nlights folder) but they didn't work and the tile selector (in LightGen2) doesn't have the range to get to ATAJ and ASAJ etc. Do I need some number of contiguous tiles to make it work? In Seattle there are quite a few holes. :-waveRegards,Jon Point