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Guest Quaxo

UK: a strange thing...

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I noticed a strange thing about UK... See the attached screenshots... they are at the same scale, one from Seattle, the other from London City. It seems that for lower res levels, the Seattle and Sanfran sceneries are much much clearer, even though in-flight, the near scenery for UK is much much clearer than the original sceneries. Why? Maybe this is due to how the lower levels are created... Some technical info? How does GenQuadrant create the lower levels? For each step, does it just take one out of 4 pixels, or does it calculate a mean? This would seem the most correct thing to do... An effect of this is that this scenery isn't very nice in the distance with FSAA off. Could Genquadrant be modified to correct this? Or maybe someone could write a small program, similar to "level57maker", which takes the Level 0 maps, and creates all the other levels, but calculating the "mean" of the pixels? I hope I explained well what I mean...Cristian

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wow the UK scenery shot looks like one of those pictures you are supposed to stare at to see a hidden 3D image :-lolwhatever they're called...

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Yes, I know what you mean. (I heard them being called "magic eye"). But if you look closely, you can see two little lakes in the north-center part, and east of them, there's the Heathrow airport! Not easy to spot though...I was wondering if the difference between these sceneries is because the original sceneries were hand-colored... ?!?I attached two map shots, one of London City, one of Seattle. As you can see, the London one is much much clearer, more detailed, and with more colors. So, in Seattle, the lower levels, even if taking one pixel out of 4, take a similar color (this doesn't happen with London, where there are "quick" color changes).So, anyone willing to write a tool to calculate the lower levels using a "mean" color ??? :)Cristian

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the main difference between Seattle and UK scenery is the compression UK region are all uncompressed .bin filesSeattle and Sanfrancisco are compressed .cpd files for levels 0, 1 and 2level 3 and up is the uncompressed again.see file and compression description at http://www.agtim.ch/fu3/compression.html:-wave agtim

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Is it the compression that makes the Seattle and Sanfran regions less detailed? There are almsot no colors, just brown in the Seattle area on that screenshot, while the UK region has much greater detail.Or is it simply the UK source images being of better quality than those for Sanfran and Seattle?

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I don't think it's only the compression (the algorythm is supposed to be lossless). Regarding SF, I believe it's due to the B/W nature of the photos (which were then hand-colored). Something of that sort must have happened to Seattle... I can't believe that colors are so "homogeneous"...Cristian

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